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1
Yang, Haobo, Jichao Li, Hao Yu, Feng Peng, and Hongjuan Wang. "Metal-Foam-Supported Pd/Al2O3 Catalysts for Catalytic Combustion of Methane: Effect of Interaction between Support and Catalyst." International Journal of Chemical Reactor Engineering 13, no. 1 (2015): 83–93. http://dx.doi.org/10.1515/ijcre-2014-0009.
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Abstract Structured Pd/Al2O3 catalysts were fabricated by impregnating Pd onto Ni and Cu foams coated with Al2O3 layers. By testing the adhesion stability and catalytic activity in the combustion of methane, the superior performance of Ni-foam-supported Pd/Al2O3 catalyst was demonstrated, to its counterpart powder catalysts. The resultant structured catalysts enable the fabrication of lamellar microreactor systems. It is found that the metal foams influence the activity of catalyst layer, due to the diffusive penetration of metallic atoms into catalysts from metal foams. The Ni foam is beneficial for enhancing the activity of Pd/Al2O3 catalyst, while the Cu foam plays a negative role. The investigation to the model powder catalysts doped with Ni and Cu verified the modification of Ni and Cu to the physicochemical properties of Pd/Al2O3 catalyst, thereby the catalytic performances. Thus, it can be expected that the performance of structured catalysts may be improved by rationally designing and selecting proper supports.
2
Xiao, Yan, Nannan Zhan, Jie Li, Yuan Tan, and Yunjie Ding. "Highly Selective and Stable Cu Catalysts Based on Ni–Al Catalytic Systems for Bioethanol Upgrading to n-Butanol." Molecules 28, no. 15 (2023): 5683. http://dx.doi.org/10.3390/molecules28155683.
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The catalytic upgrading of ethanol into butanol through the Guerbet coupling reaction has received increasing attention recently due to the sufficient supply of bioethanol and the versatile applications of butanol. In this work, four different supported Cu catalysts, i.e., Cu/Al2O3, Cu/NiO, Cu/Ni3AlOx, and Cu/Ni1AlOx (Ni2+/Al3+ molar ratios of 3 and 1), were applied to investigate the catalytic performances for ethanol conversion. From the results, Ni-containing catalysts exhibit better reactivity; Al-containing catalysts exhibit better stability; but in terms of ethanol conversion, butanol selectivity, and catalyst stability, a corporative effect between Ni–Al catalytic systems can be clearly observed. Combined characterizations such as XRD, TEM, XPS, H2-TPR, and CO2/NH3-TPD were applied to analyze the properties of different catalysts. Based on the results, Cu species provide the active sites for ethanol dehydrogenation/hydrogenation, and the support derived from Ni–Al–LDH supplies appropriate acid–base sites for the aldol condensation, contributing to the high butanol selectivity. In addition, catalysts with strong reducibility (i.e., Cu/NiO) may be easily deconstructed during catalysis, leading to fast deactivation of the catalysts in the Guerbet coupling process.
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Han, Dongmei, Yong Chen, Shuanjin Wang, Min Xiao, Yixin Lu, and Yuezhong Meng. "Effect of Alkali-Doping on the Performance of Diatomite Supported Cu-Ni Bimetal Catalysts for Direct Synthesis of Dimethyl Carbonate." Catalysts 8, no. 8 (2018): 302. http://dx.doi.org/10.3390/catal8080302.
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Alkali-adopted Cu-Ni/diatomite catalysts were designed and used for the direct synthesis of dimethyl carbonate (DMC) from carbon dioxide and methanol. Alkali additives were introduced into Cu-Ni/diatomite catalyst as a promoter because of its lower work function (Ni > Cu > Li > Na > K > Cs) and stronger electron-donating ability. A series of alkali-promoted Cu-Ni/diatomite catalysts were prepared by wetness impregnation method with different kind and different loading of alkali. The synthesized catalysts were fully characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), temperature-programmed reduction (TPR), and NH3/CO2-TPD. The experimental results demonstrated that alkali adoption can significantly promote the catalytic activity of Cu–Ni bimetallic catalysts. Under the catalytic reaction conditions of 120 °C and 1.0 MPa; the highest CH3OH conversion of 9.22% with DMC selectivity of 85.9% has been achieved when using 15%(2Cu-Ni) 2%Cs2O/diatomite catalyst (CuO + NiO = 15 wt. %, atomic ratio of Cu/Ni = 2/1, Cs2O = 2 wt. %).
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Pudi, Satyanarayana Murty, Tarak Mondal, Prakash Biswas, Shalini Biswas та Shishir Sinha. "Conversion of Glycerol into Value-Added Products Over Cu–Ni Catalyst Supported on γ-Al2O3 and Activated Carbon". International Journal of Chemical Reactor Engineering 12, № 1 (2014): 151–62. http://dx.doi.org/10.1515/ijcre-2013-0102.
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Abstract A series of Cu, Ni monometallic and bimetallic catalysts supported on γ-Al2O3 and activated carbon were synthesized by incipient wetness impregnation method and examined for hydrogenolysis and esterification of glycerol. Hydrogenolysis reaction was carried out in a 250 ml Teflon-coated stainless steel batch reactor at 250°C and 10 bar H2 pressure, whereas esterification of glycerol with acetic acid was carried out at 120°C at atmospheric pressure. The physiochemical properties of the catalysts were investigated by various techniques such as surface area, X-ray diffraction (XRD), NH3-temperature-programmed desorption (TPD). Characterization results dictated that the reduction behavior, acidic nature and the metal support interactions were varied with the support as well as Cu/Ni weight ratio. The XRD results confirmed the formation of mixed oxide Cu0.75Ni0.25 Al2O4 phase in Cu–Ni (3:1)/γ-Al2O3 catalyst. Among the catalysts tested, Cu–Ni bimetallic catalysts showed superior performance as compared to monometallic catalysts in both the reactions. The glycerol hydrogenolysis activity of γ-Al2O3 supported Cu–Ni catalysts was higher than the activated carbon-supported catalysts. 1,2-PDO was obtained as the main hydrogenolysis product independent of the support as well as Cu/Ni weight ratio and its selectivity was in the range of 92.8–98.5%. The acidic nature of γ-Al2O3 and the mixed oxide (Cu0.75Ni0.25Al2O4) phase played an important role for hydrogenolysis activity. Cu–Ni (3:1)/γ-Al2O3 catalyst showed the maximum 1,2-PDO selectivity to 97% with 27% glycerol conversion after a reaction time of 5 h. On the other hand, Cu–Ni(1:3)/C catalyst showed the highest glycerol conversion of 97.4% for esterification and obtained selectivity to monoacetin, diacetin and triacetin were 26.1%, 67.2% and 6.5%, respectively.
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Hasnan, Nur Shamimie Nadzwin, Manoj Pudukudy, Zahira Yaakob, Nur Hidayatul Nazirah Kamarudin, Kean Long Lim, and Sharifah Najiha Timmiati. "Promoting Effects of Copper and Iron on Ni/MSN Catalysts for Methane Decomposition." Catalysts 13, no. 7 (2023): 1067. http://dx.doi.org/10.3390/catal13071067.
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Copper and iron-based bimetallic nickel catalysts supported on Mesostructured Silica Nanoparticles (MSNs) with compositions of 50% Ni–5% Cu/MSN and 50% Ni–5% Fe/MSN were prepared using an impregnation method, and they were compared with a monometallic 50% Ni–MSN catalyst for their activity and stability in methane decomposition reaction. The influence of promoters, such as Cu and Fe, at different reaction temperatures (700 °C, 800 °C and 900 °C) was investigated. The results revealed that the Cu and Fe-promoted catalysts significantly increased the hydrogen yield in methane decomposition compared with the unpromoted catalyst. This could be attributed to the formation of Ni–Cu and Ni–Fe bimetallic alloys in the catalysts, respectively, and this favored the stability of the catalysts. With increasing reaction temperature, the hydrogen yield also increased. However, the hydrogen yield and the lifetime of the nickel catalyst were enhanced upon the addition of iron compared to copper at all the reaction temperatures. The analysis conducted over the spent catalysts validated the formation of multi-walled carbon nanotubes with a bamboo-like internal channel over the catalysts along with a high crystallinity and graphitization degree of the carbon produced.
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Gai, Pratibha L. "In Situ Electron Microscopy in catalysis research and related surface reactions." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 614–15. http://dx.doi.org/10.1017/s0424820100155049.
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Catalysis plays a major role in the modern oil and chemical industries. Solid state catalysts are most common, whilst the reactants are commodity gases and liquids. The performance of the catalysts depends strongly on their microstructure, chemistry and surface structures on a fine (nanometer) scale and electron microscopy (EM) plays an increasingly important role in the characterization. In-situ EM with an environmental cell permits direct observations of chemical reactions under near operating conditions and in conjunction with HREM and AEM can provide in favorable cases, significant atomic level information about the surface/microstructural changes and about possible reaction with substrates. In this paper, examples of catalyst materials in chemical technology and the nature of catalysis in alloy steels with applications in nuclear reactors are shown to elucidate this.A variety of supported metallic catalysts were examined: Ni/carbon, Cu/alumina and bimetallic Cu-Pd/C (both of interest in methanol synthesis), Cu-Ru/C (incyclohexane conversions) and Cu-Ni/alumina.
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Yang, Wen, Yanyan Feng, and Wei Chu. "Catalytic Chemical Vapor Deposition of Methane to Carbon Nanotubes: Copper Promoted Effect of Ni/MgO Catalysts." Journal of Nanotechnology 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/547030.
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The Ni/MgO and Ni-Cu/MgO catalysts were prepared by sol-gel method and used as the catalysts for synthesis of carbon nanotubes by thermal chemical vapor deposition. The effect of Cu on the carbon yield and structure was investigated, and the effects of calcination temperature and reaction temperature were also investigated. The catalysts and synthesized carbon materials were characterized by temperature programmed reduction (TPR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Results showed that the addition of Cu promoted the reduction of nickel species, subsequently improving the growth and yield of CNTs. Meanwhile, CNTs were synthesized by the Ni/MgO and Ni-Cu/MgO catalysts with various calcination temperatures and reaction temperatures, and results suggested that the obtained CNTs on Ni-Cu/MgO catalyst with the calcination temperature of 500°C and the reaction temperature of 650°C were of the greatest yield and quantity of 927%.
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Zhu, Tianhan, Hua Song, Feng Li та Yanguang Chen. "Hydrodeoxygenation of Benzofuran over Bimetallic Ni-Cu/γ-Al2O3 Catalysts". Catalysts 10, № 3 (2020): 274. http://dx.doi.org/10.3390/catal10030274.
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Bimetallic NixCu(10−x)/γ-Al2O3 catalysts (where x is the mass fraction of Ni) with different Ni/Cu mass ratios were prepared. The catalysts were characterized by X-ray diffractometry, N2 adsorption–desorption, inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy, H2-temperature programmed reduction, and transmission electron microscopy. The effect of Ni/Cu mass ratio on benzofuran hydrodeoxygenation was investigated in a fixed-flow reactor. Cu addition improved the NiO reducibility. The strong interaction of Ni and Cu led to the formation of smaller and highly dispersed CuO and NiO species over γ-Al2O3, which favors an improvement in catalytic activity. Among the as-prepared catalysts, the Ni5Cu5/γ-Al2O3 showed the highest deoxygenated product yield (79.9%) with an acceptable benzofuran conversion of 95.2%, which increased by 18.3% and 16.9% compared with that of the monometallic Ni/γ-Al2O3 catalyst. A possible reaction network was proposed, which would provide insight into benzofuran hydrodeoxygenation over the Ni5Cu5/γ-Al2O3 catalyst.
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Jun, Uidam, Bon-Jun Ku, Yeji Gwon, et al. "Influence of Metal Composition and Support Material on Carbon Yield and Quality in the Direct Decomposition of Methane." Molecules 30, no. 9 (2025): 1903. https://doi.org/10.3390/molecules30091903.
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A series of catalysts were synthesized via a combination of evaporation-induced self-assembly and spray pyrolysis; they were then applied to the direct decomposition of methane. Among them, Ni-Cu/MgO catalysts exhibited the smallest Ni particle size (~9 nm), attributed to the Cu-induced suppression of Ni crystal growth during synthesis. These catalysts achieved the highest carbon yield, primarily due to the enhanced dispersion and nanoscale size of Ni particles. The interaction between methane and the catalysts, as well as the structural and electrical properties of the resulting carbon nanotubes, such as crystallinity and conductivity, were investigated with respect to the support material (MgO vs. Al2O3) and metal composition (Ni vs. Ni-Cu). The findings provide valuable insights for designing advanced catalyst systems for the efficient conversion of methane into high-value carbon-based materials.
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Gousi, Mantha, Eleana Kordouli, Kyriakos Bourikas, et al. "Green Diesel Production over Nickel-Alumina Nanostructured Catalysts Promoted by Copper." Energies 13, no. 14 (2020): 3707. http://dx.doi.org/10.3390/en13143707.
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A series of nickel–alumina catalysts promoted by copper containing 1, 2, and 5 wt. % Cu and 59, 58, and 55 wt. % Ni, respectively, (symbols: 59Ni1CuAl, 58Ni2CuAl, 55Ni5CuAl) and a non-promoted catalyst containing 60 wt. % Ni (symbol: 60NiAl) were prepared following a one-step co-precipitation method. They were characterized using various techniques (N2 sorption isotherms, XRD, SEM-EDX, XPS, H2-TPR, NH3-TPD) and evaluated in the selective deoxygenation of sunflower oil using a semi-batch reactor (310 °C, 40 bar of hydrogen, 96 mL/min hydrogen flow rate, and 100 mL/1 g reactant to catalyst ratio). The severe control of the co-precipitation procedure and the direct reduction (without previous calcination) of precursor samples resulted in mesoporous nano-structured catalysts (most of the pores in the range 3–5 nm) exhibiting a high surface area (192–285 m2 g−1). The promoting action of copper is demonstrated for the first time for catalysts with a very small Cu/Ni weight ratio (0.02–0.09). The effect is more pronounced in the catalyst with the medium copper content (58Ni2CuAl) where a 17.2% increase of green diesel content in the liquid products has been achieved with respect to the non-promoted catalyst. The copper promoting action was attributed to the increase in the nickel dispersion as well as to the formation of a Ni-Cu alloy being very rich in nickel. A portion of the Ni-Cu alloy nanoparticles is covered by Ni0 and Cu0 nanoparticles in the 59Ni1CuAl and 55Ni5CuAl catalysts, respectively. The maximum promoting action observed in the 58Ni2CuAl catalyst was attributed to the finding that, in this catalyst, there is no considerable masking of the Ni-Cu alloy by Ni0 or Cu0. The relatively low performance of the 55Ni5CuAl catalyst with respect to the other promoted catalysts was attributed, in addition to the partial coverage of Ni-Cu alloy by Cu0, to the remarkably low weak/moderate acidity and relatively high strong acidity exhibited by this catalyst. The former favors selective deoxygenation whereas the latter favors coke formation. Copper addition does not affect the selective-deoxygenation reactions network, which proceeds predominantly via the dehydration-decarbonylation route over all the catalysts studied.
11
Polychronopoulou, Kyriaki, Nikolaos Charisiou, Kyriakos Papageridis, et al. "The Effect of Ni Addition onto a Cu-Based Ternary Support on the H2 Production over Glycerol Steam Reforming Reaction." Nanomaterials 8, no. 11 (2018): 931. http://dx.doi.org/10.3390/nano8110931.
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In the present study, Ni/Ce-Sm-xCu (x = 5, 7, 10 at.%) catalysts were prepared using microwave radiation coupled with sol-gel and followed by wetness impregnation method for the Ni incorporation. Highly dispersed nanocrystallites of CuO and NiO on the Ce-Sm-Cu support were found. Increase of Cu content seems to facilitate the reducibility of the catalyst according to the H2 temperature-programmed reduction (H2-TPR). All the catalysts had a variety of weak, medium and strong acid/basic sites that regulate the reaction products. All the catalysts had very high XC3H8O3 for the entire temperature (400–750 °C) range; from ≈84% at 400 °C to ≈94% at 750 °C. Ni/Ce-Sm-10Cu catalyst showed the lowest XC3H8O3-gas implying the Cu content has a detrimental effect on performance, especially between 450–650 °C. In terms of H2 selectivity (SH2) and H2 yield (YH2), both appeared to vary in the following order: Ni/Ce-Sm-10Cu > Ni/Ce-Sm-7Cu > Ni/Ce-Sm-5Cu, demonstrating the high impact of Cu content. Following stability tests, all the catalysts accumulated high amounts of carbon, following the order Ni/Ce-Sm-5Cu < Ni/Ce-Sm-7Cu < Ni/Ce-Sm-10Cu (52, 65 and 79 wt.%, respectively) based on the thermogravimetric analysis (TGA) studies. Raman studies showed that the incorporation of Cu in the support matrix controls the extent of carbon graphitization deposited during the reaction at hand.
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Zhou, Long, Li Ping Ma, Ze Cheng Zi, Jun Ma, and Jian Tao Chen. "Study on Ni Catalytic Hydrogenation of Carbon Dioxide for Methane." Applied Mechanics and Materials 628 (September 2014): 16–19. http://dx.doi.org/10.4028/www.scientific.net/amm.628.16.
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Catalyst by different carriers prepared of carbon dioxide conversion sequence is: Ni/TiO2> Ni/γ-Al2O3> Ni/MgO > Ni/SiO2. Second metal, Co, Mn, Cu, La and Ce, was significantly enhanced the activity of methanation nickel-based catalysts in the carbon dioxide methanation reaction, but second metal of Cu was bad for the activity of methanation. The 10%Ni/Al2O3 and 2.5%Ce-10%Ni/Al2O3 catalysts were characterized by TG and H2-TPR，it was revealed to Ce which is benefit for reduce NiO reduction temperature and the optimal reduction temperature of the catalysts in between 400°C and 500 °C
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Tepamatr, Pannipa, Pattarapon Rungsri, Pornlada Daorattanachai, and Navadol Laosiripojana. "Maximizing H2 Production from a Combination of Catalytic Partial Oxidation of CH4 and Water Gas Shift Reaction." Molecules 30, no. 2 (2025): 271. https://doi.org/10.3390/molecules30020271.
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A single-bed and dual-bed catalyst system was studied to maximize H2 production from the combination of partial oxidation of CH4 and water gas shift reaction. In addition, the different types of catalysts, including Ni, Cu, Ni-Re, and Cu-Re supported on gadolinium-doped ceria (GDC) were investigated under different operating conditions of temperature (400–650 °C). Over Ni-based catalysts, methane can easily dissociate on a Ni surface to give hydrogen and carbon species. Then, carbon species react with lattice oxygen of ceria-based material to form CO. The addition of Re to Ni/GDC enhances CH4 dissociation on the Ni surface and increases oxygen storage capacity in the catalyst, thus promoting carbon elimination. In addition, the results showed that a dual-bed catalyst system exhibited catalytic activity better than a single-bed catalyst system. The dual-bed catalyst system, by the combination of 1%Re4%Ni/GDC as a partial oxidation catalyst and 1%Re4%Cu/GDC as a water gas shift catalyst, provided the highest CH4 conversion and H2 yield. An addition of Re onto Ni/GDC and Cu/GDC caused an increase in catalytic performance because Re addition could improve the catalyst reducibility and increase metal surface area, as more of their surface active sites are exposed to reactants.
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Gebresillase, Mahlet N., Reibelle Q. Raguindin, Hern Kim та Jeong Gil Seo. "Supported Bimetallic Catalysts for the Solvent-Free Hydrogenation of Levulinic Acid to γ-Valerolactone: Effect of Metal Combination (Ni-Cu, Ni-Co, Cu-Co)". Catalysts 10, № 11 (2020): 1354. http://dx.doi.org/10.3390/catal10111354.
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γ-valerolactone (GVL) is an important value-added chemical with potential applications as a fuel additive, a precursor for valuable chemicals, and polymer synthesis. Herein, different monometallic and bimetallic catalysts supported on γ-Al2O3 nanofibers (Ni, Cu, Co, Ni-Cu, Ni-Co, Cu-Co) were prepared by the incipient wetness impregnation method and employed in the solvent-free hydrogenation of levulinic acid (LA) to GVL. The influence of metal loading, metal combination, and ratio on the activity and selectivity of the catalysts was investigated. XRD, SEM-EDS, TEM, H2-TPR, XPS, NH3-TPD, and N2 adsorption were used to examine the structure and properties of the catalysts. In this study, GVL synthesis involves the single-step dehydration of LA to an intermediate, followed by hydrogenation of the intermediate to GVL. Ni-based catalysts were found to be highly active for the reaction. [2:1] Ni-Cu/Al2O3 catalyst showed 100.0% conversion of LA with >99.0% selectivity to GVL, whereas [2:1] Ni-Co/Al2O3 yielded 100.0% conversion of LA with 83.0% selectivity to GVL. Moreover, reaction parameters such as temperature, H2 pressure, time, and catalyst loading were optimized to obtain the maximum GVL yield. The solvent-free hydrogenation process described in this study propels the future industrial production of GVL from LA.
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Chen, Yu-Jia, Song-Hui Huang, Jun-Yen Uan, and Hao-Tung Lin. "Synthesis of Catalytic Ni/Cu Nanoparticles from Simulated Wastewater on Li–Al Mixed Metal Oxides for a Two-Stage Catalytic Process in Ethanol Steam Reforming: Catalytic Performance and Coke Properties." Catalysts 11, no. 9 (2021): 1124. http://dx.doi.org/10.3390/catal11091124.
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This work recovered Ni or Cu cations from simulated electroplating wastewater to synthesize Ni/Cu nano-catalysts for H2 generation by ethanol steam reforming (ESR). Aluminum lathe waste was used as a framework to prepare the structured catalyst. Li–Al–CO3 layered double hydroxide (LDH) was electrodeposited on the surface of the framework. The LDH was in a platelet-like structure, working as a support for the formation of the precursor of the metal catalysts. The catalytic performance and the coke properties of a 6Cu_6Ni two-stage catalyst configuration herein used for ESR catalytic reaction were studied. The Cu–Ni two-stage catalyst configuration (6Cu_6Ni) yielded more H2 (~10%) than that by using the Ni-based catalyst (6Ni) only. The 6Cu_6Ni catalyst configuration also resulted in a relatively stable H2 generation rate vs. time, with nearly no decline during the 5-h reaction. Through the pre-reaction of ethanol-steam mixture with Cu/LiAlO2 catalyst, the Ni/LiAlO2 catalyst in the 6Cu_6Ni catalyst configuration could steadily decompose acetaldehyde, and rare acetate groups, which would evolve condensed coke, were formed. The Ni nanoparticles were observed to be lifted and separated by the carbon filaments from the support and had no indication of sintering, contributing to the bare deactivation of the Ni/LiAlO2 catalyst in 6Cu_6Ni.
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Yutomo, Erik Bhekti, Oki Ade Putra, and Suci Faniandari. "Kinetic Study of Few Layer Graphene Growth on Cu-Ni Alloy Catalyst: A Density Functional Theory Approach." International Journal of Research and Review 12, no. 5 (2025): 19–24. https://doi.org/10.52403/ijrr.20250503.
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The tunable electronic and optical properties of few layer graphene (FLG) make it potential for transparent conductive electrode applications. The FLG with precisely controlled number of layers can be grown using Chemical Vapor Deposition (CVD) method on the Cu-Ni alloy catalyst. However, the effect of Ni atom concentration in the Cu-Ni alloy catalyst on the FLG growth mechanism is still not fully understood. The kinetic aspect studies still need to be conducted to get a comprehensive picture of the growth process. Therefore, in this study, we use the density functional theory method to study the effect of Ni atom concentration on the growth mechanism of graphene on Cu-Ni alloy catalyst from the kinetic aspect. We consider two catalyst models, namely Cu-Ni-1 (6.25 at % Ni) and Cu-Ni-3 (18.75 at % Ni) catalysts and two kinetic processes, namely diffusion of C atoms over the catalyst surface and diffusion of C atoms from the surface to the subsurface of the catalyst. We found that increasing the concentration of Ni atoms causes a reduction in the activation energy of the diffusion of C atoms from the surface to the subsurface of the catalyst, which in the case of Cu-Ni-2 catalyst is 0.16 eV. This activation energy is lower than the single atom energy at the graphene growth temperature (0.17 eV). This result indicates that Cu-Ni catalysts with Ni atom concentrations greater than 18.75% can be used to grow FLG with precisely controlled number of layers. This finding can be used as a guidance for experimental research in order to grow few layer graphene with high quality. Keywords: density functional theory, electronic conductivity, few-layer graphene, transmittance
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Al-Anazi, Abdulaziz, Omer Bellahwel, Kavitha C., et al. "Promoter Impact on 5Ni/SAPO-5 Catalyst for H2 Production via Methane Partial Oxidation." Catalysts 14, no. 5 (2024): 316. http://dx.doi.org/10.3390/catal14050316.
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Compared to steam reforming techniques, partial oxidation of methane (POM) is a promising technology to improve the efficiency of synthesizing syngas, which is a mixture of CO and H2. In this study, partial oxidation of methane (POM) was used to create syngas, a combination of CO and H2, using the SAPO-5-supported Ni catalysts. Using the wetness impregnation process, laboratory-synthesized Ni promoted with Sr, Ce, and Cu was used to modify the SAPO-5 support. The characterization results demonstrated that Ni is appropriate for the POM due to its crystalline structure, improved metal support contact, and increased thermal stability with Sr, Ce, and Cu promoters. During POM at 600 °C, the synthesized 5Ni+1Sr/SAPO-5 catalyst sustained stability for 240 min on stream. While keeping the reactants stoichiometric ratio of (CH4:O2 = 2:1), the addition of Sr promoter and active metal Ni to the SAPO-5 increased the CH4 conversion from 41.13% to 49.11% and improved the H2/CO ratio of 3.33. SAPO-5-supported 5Ni+1Sr catalysts have great potential for industrial catalysis owing to their unique combination of several oxides. This composition not only boosts the catalyst’s activity but also promotes favorable physiochemical properties, resulting in improved production of syngas. Syngas is a valuable intermediate in various industrial processes.
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Sukackienė, Zita, Gitana Valeckytė, Virginija Kepenienė, et al. "Non-Precious Metals Catalysts for Hydrogen Generation." Coatings 13, no. 10 (2023): 1740. http://dx.doi.org/10.3390/coatings13101740.
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In this paper, the generation of hydrogen from alkaline sodium borohydride solution by hydrolysis is studied. To obtain catalysts for efficient hydrogen generation, Ni, Mn, Mo, and Co metals were deposited on the Cu surface by the simple electroless metal deposition method using morpholine borane as a reducing agent. Depending on the peculiarities of the deposition of each metal, the coating thickness was ca. 1 μm for all catalysts. The deposited coatings were compact and crack-free, with multilayer characteristics and a cauliflower-like structure. The prepared Ni/Cu, NiMn/Cu, NiMo/Cu, NiCo/Cu, NiCoMn/Cu, NiCoMo/Cu, and NiCoMoMn/Cu catalysts showed an efficient catalytic activity for sodium borohydride hydrolysis reaction. The lowest activation energy of 45.3 kJ mol−1 for sodium borohydride hydrolysis reaction was obtained using the NiCoMoMn/Cu catalyst. The highest hydrogen generation rate of 3.08 mL min−1 was also achieved using this catalyst at 303 K. With a further increase in temperature to 343 K, the hydrogen generation rate catalyzed by the NiCoMoMn/Cu increased 7.7 times and reached 23.57 mL min−1.
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Liu, Lili, Xiaojing Zhou, Li Liu, et al. "Heterogeneous Bimetallic Cu–Ni Nanoparticle-Supported Catalysts in the Selective Oxidation of Benzyl Alcohol to Benzaldehyde." Catalysts 9, no. 6 (2019): 538. http://dx.doi.org/10.3390/catal9060538.
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Three bimetallic Cu–Ni nanoparticle-supported catalysts were synthesized by co-immobilization followed by H2 reduction. A chromium(III) terephthalate metal organic framework (MIL-101), titanium dioxide (TiO2), and carbon (C) with different properties (acidity and Brunauer–Emmett–Teller surface area) were selected as supports for studying the effect of the support nature on the catalytic activity and selectivity in the oxidation of benzyl alcohol. The physicochemical properties of the Cu–Ni-supported catalysts were characterized by XRD, NH3-TPD, nitrogen adsorption/desorption, TEM, EDS, XPS, and ICP-OES. Bimetallic Cu–Ni nanoparticles were highly dispersed on the support. The catalytic activities of CuNi/MIL-101, CuNi/TiO2, and CuNi/C were tested in the selective oxidation of benzyl alcohol to benzaldehyde in the presence of molecular oxygen under mild reaction conditions. The highest benzaldehyde yields were achieved with CuNi/TiO2, CuNi/MIL-101, and CuNi/C catalysts at 100 °C within 4 h under 5, 3, and 3 bar of O2, respectively. The bimetallic Cu–Ni-supported catalysts possessed two types of catalytic active sites: acid sites and bimetallic Cu–Ni nanoparticles. The CuNi/MIL-101 catalyst possessed a high number of acid sites and exhibited high yield during selective benzyl alcohol oxidation to benzaldehyde. Importantly, the catalysts exhibited a high functional group (electron-donating and electron-withdrawing groups) tolerance. Cu–Ni-supported catalysts with an Cu:Ni mole ratio of 1:1 exhibited the highest yield of 47% for the selective oxidation of benzyl alcohol to benzaldehyde. Reusability and leaching experiment results exhibited that CuNi/MIL-101 showed better stability than CuNi/TiO2 and CuNi/C catalysts due to the large porous cavities of MIL-101 support; these cavities can be used to trap bimetallic Cu–Ni nanoparticles and inhibit nanoparticle leaching.
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Tahir, Saad, and Hallo Askari. "Catalytic Abatement of VOCs: Aerobic Combustion of Methane or Ethane over Alumina-Supported Metal Oxides Recovered from Spent Catalysts." Environment and Natural Resources Research 10, no. 2 (2020): 33. http://dx.doi.org/10.5539/enrr.v10n2p33.
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&gamma;-Al2O3 supported Cu, Cu-Zn and Cu-Ni-Fe-Zn oxide catalysts were prepared using leachate transition metal nitrate and sulfate aqueous solutions from commercial spent catalysts. A bench-scale rig was used to investigate the combustion activity of these catalysts toward methane or ethane in the air stream (1000 ppmv) at a space velocity of 20,000 h-1. The Cu-Ni-Fe-Zn oxides/&gamma;-Al2O3 catalyst proved to be the most active catalyst for the combustion of methane in the temperature range 290-575&deg;C and of ethane in the lower temperature range of 275-525oC as compared to Cu and Cu-Zn oxide loaded catalysts. X-ray powder diffractograms indicated that the metal oxide species were highly dispersed or amorphous on the alumina surface in all the catalysts except for the detection of a minority phase of monoclinic CuO on the Cu-containing mono-metallic catalysts. The co-existence of ZnO in the CuO catalysts suppresses the activity of the copper oxide species and, therefore, the conversion of methane or ethane was reduced. The present research endeavor provides proof-of-concept that relatively inexpensive metal oxide-based heterogeneous catalysts for VOCs abatement can be recovered from spent catalysts. Hence, environmental and health threats of improper handling of VOCs or spent catalysts may be alleviated.
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Azri, Norsahida, Irmawati Ramli, Usman Idris Nda-Umar, Mohd Izham Saiman, and Yun Hin Taufiq-Yap. "Effect of Different Metal Modified Dolomite Catalysts on Catalytic Glycerol Hydrogenolysis towards 1,2-Propanediol." Sains Malaysiana 51, no. 5 (2022): 1385–98. http://dx.doi.org/10.17576/jsm-2022-5105-10.
Full textAbstract:
A series of metal modified dolomite catalysts (10%Ni-20%Cu/Dol, 10%Co-20%Cu/Dol, 10%Fe-20%Cu/Dol, 10%Zn-20%Cu/DolNi) were synthesized via method of impregnation, later calcined at 500 ℃ and reduced by 5%H2 at 600 ℃. Those catalysts were formerly tested for their physico-chemical properties by BET, BJH, XRD, H2-TPR, NH3–TPD, CO2-TPD and SEM, and followed by evaluation in catalytic performance of glycerol hydrogenolysis to 1,2-propanediol (1,2-PDO). Among the examined catalysts, 10%Ni-20%Cu/Dol showed optimum hydrogenolysis activity owing to the good copper-nickel-dolomite interaction. The outcomes from the characterizations disclosed that the presence of nickel-copper species which principally enriched on dolomite surface thereby enhanced the properties of the catalyst in terms of good metal reducibility along with the presence of adequate catalyst acidity. All the good features of 10%Ni-20%Cu/Dolcatalyst added to its high activity with 83.5% glycerol conversion (GC) and 75% 1,2-PDO with low methanol as side reaction product under 200 ℃, 4 MPa H2 and 10 h duration test, 1 g catalyst dosage and 20 wt% glycerol concentration.
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Balaga, Ravi, Putrakumar Balla, Xiaoqiang Zhang, et al. "Enhanced Cyclopentanone Yield from Furfural Hydrogenation: Promotional Effect of Surface Silanols on Ni-Cu/m-Silica Catalyst." Catalysts 13, no. 3 (2023): 580. http://dx.doi.org/10.3390/catal13030580.
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A direct alkaline hydrothermal method was used to synthesize mono- and bimetallic Ni and Cu on mesoporous silica (m-SiO2) as catalysts for the hydrogenation of furfural (FAL) to cyclopentanone (CPO). The catalysts were characterized by XRD, FTIR, H2-TPR, SEM, TEM, HR-TEM, XPS, ICP, BET, and CHN analysis. The results demonstrate that the addition of Cu metal improved the reducibility of Ni catalysts and revealed Ni-Cu alloy formation over m-SiO2. Furthermore, XPS and FTIR results reveal that the silanol groups on the catalyst surface play an important role in the ring rearrangement of furfuryl alcohol. Hence, the effect of silanol groups in the FOL rearrangement was studied in detail. Among the catalysts at fixed metal loading of 20 wt.%, Ni5Cu15/m-SiO2 catalyzed the formation of CPO as the main product due to the synergy of Ni-Cu alloy and surface silanol groups. Ni5Cu15 supported on a commercial mesoporous silica (Ni5Cu15/C-SiO2) showed inferior performance compared with the Ni5Cu15/m-SiO2 catalyst for the FAL hydrogenation. Reaction temperature and time were also optimized for the enhanced CPO yield over Ni5Cu15/m-SiO2. The Ni5Cu15/m-SiO2 catalyst is durable, as demonstrated by stability tests over multiple reuses. This effective and flexible NixCuy on m-SiO2 catalyst provides an effective candidate for efficient upgrading of furanics in selective hydrogenation reactions.
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Xiao, Yan, Jie Li, Yuan Tan, et al. "Ni-Based Hydrotalcite (HT)-Derived Cu Catalysts for Catalytic Conversion of Bioethanol to Butanol." International Journal of Molecular Sciences 24, no. 19 (2023): 14859. http://dx.doi.org/10.3390/ijms241914859.
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Catalytic conversion of biomass-derived ethanol into n-butanol through Guerbet coupling reaction has become one of the key reactions in biomass valorization, thus attracting significant attention recently. Herein, a series of supported Cu catalysts derived from Ni-based hydrotalcite (HT) were prepared and performed in the continuous catalytic conversion of ethanol into butanol. Among the prepared catalysts, Cu/NiAlOx shows the best performance in terms of butanol selectivity and catalyst stability, with a sustained ethanol conversion of ~35% and butanol selectivity of 25% in a time-on-stream (TOS) of 110 h at 280 °C. While for the Cu/NiFeOx and Cu/NiCoOx, obvious catalyst deactivation and/or low butanol selectivity were obtained. Extensive characterization studies of the fresh and spent catalysts, i.e., X-ray diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Hydrogen temperature-programmed reduction (H2-TPR), reveal that the catalysts’ deactivation is mainly caused by the support deconstruction during catalysis, which is highly dependent on the reducibility. Additionally, an appropriate acid–base property is pivotal for enhancing the product selectivity, which is beneficial for the key process of aldol-condensation to produce butanol.
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Mosinska, Magdalena, Natalia Stępińska, Waldemar Maniukiewicz, et al. "Hydrogen Production on Cu-Ni Catalysts via the Oxy-Steam Reforming of Methanol." Catalysts 10, no. 3 (2020): 273. http://dx.doi.org/10.3390/catal10030273.
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In this work, bimetallic Cu-Ni catalysts supported on binary oxides containing ZnO, ZrO2, CeO2 and Al2O3 were investigated in hydrogen production via the oxidative steam reforming of methanol (OSRM). Their physicochemical properties were extensively studied using various methods such as BET, TPR-H2, TPD-NH3, XRD, SEM-EDS, ToF-SIMS and XPS. The reactivity measurements showed that the active phase and support composition played an important role in the activity of the catalyst in the OSRM. The most active system at higher temperatures was 30% Cu–10% Ni/CeO2·Al2O3, with high catalytic activity attributed to the Cu0.8Ni0.2 alloy formation. In addition, the reactivity results showed that the most active catalyst exhibited high acidity and was easily reduced. At low temperatures, the best catalytic properties were exhibited by 30% Cu–10% Ni/ZrO2·Al2O3. The reactivity and physicochemical properties of the studied catalysts confirmed the crucial role of alloy composition on their catalytic properties in the oxy-steam reforming of methanol. The obtained results validate the possibility of using Cu-Ni catalysts for hydrogen production.
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Gulyaeva, Yuliya, Maria Alekseeva (Bykova), Olga Bulavchenko, et al. "Ni–Cu High-Loaded Sol–Gel Catalysts for Dehydrogenation of Liquid Organic Hydrides: Insights into Structural Features and Relationship with Catalytic Activity." Nanomaterials 11, no. 8 (2021): 2017. http://dx.doi.org/10.3390/nano11082017.
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The heightened interest in liquid organic hydrogen carriers encourages the development of catalysts suitable for multicycle use. To ensure high catalytic activity and selectivity, the structure–reactivity relationship must be extensively investigated. In this study, high-loaded Ni–Cu catalysts were considered for the dehydrogenation of methylcyclohexane. The highest conversion of 85% and toluene selectivity of 70% were achieved at 325 °C in a fixed-bed reactor using a catalyst with a Cu/Ni atomic ratio of 0.23. To shed light on the relationship between the structural features and catalytic performance, the catalysts were thoroughly studied using a wide range of advanced physicochemical tools. The activity and selectivity of the proposed catalysts are related to the uniformity of Cu distribution and its interaction with Ni via the formation of metallic solid solutions. The method of introduction of copper in the catalyst plays a crucial role in the effectiveness of the interaction between the two metals.
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He, Deqin, Zheng Liang, Juwen Gu, Xuechun Sang, Yujia Liu, and Songbai Qiu. "Development of Robust CuNi Bimetallic Catalysts for Selective Hydrogenation of Furfural to Furfuryl Alcohol under Mild Conditions." Catalysts 14, no. 10 (2024): 683. http://dx.doi.org/10.3390/catal14100683.
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Furfuryl alcohol represents a pivotal intermediate in the high-value utilization of renewable furfural, derived from agricultural residues. The industrial-scale hydrogenation of furfural to furfuryl alcohol typically employs Cu-based catalysts, but their limited catalytic activity necessitates high-temperature and high-pressure conditions. Here, we develop robust CuNi bimetallic catalysts through direct calcination of dried sol–gel precursors under H2 atmosphere, enabling the complete conversion of furfural to furfuryl alcohol under mild conditions. By adjusting the calcination atmosphere and introducing small amounts of Ni, we achieve the formation of highly dispersed, ultrasmall Cu nanoparticles, resulting in a significant enhancement of the catalytic activity. The optimized 0.5%Ni-10%Cu/SiO2-CA(H2) catalyst demonstrates superior catalytic performance, achieving 99.4% of furfural conversion and 99.9% of furfuryl alcohol selectivity, respectively, at 55 °C under 2 MPa H2, outperforming previously reported Cu-based catalysts. The excellent performance of CuNi bimetallic catalysts can be attributed to the highly dispersed Cu nanoparticles and the synergistic effect between Cu and Ni for H2 activation. This research contributes to the rational design of Cu-based catalysts for the selective hydrogenation of furfural.
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Zhang, Jianguang, and Ningge Xu. "Hydrogen Production from Ethylene Glycol Aqueous Phase Reforming over Ni–Al Layered Hydrotalcite-Derived Catalysts." Catalysts 10, no. 1 (2020): 54. http://dx.doi.org/10.3390/catal10010054.
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By introducing Mg, Cu, Zn, Sn, and Mn into the synthesis processes of Ni and Al based hydrotalcite, Ni–Al layered hydrotalcite-derived catalysts with different metal compositions were prepared. In this paper, the effect of metal composition on the structure of Ni–Al layered hydrotalcite-derived catalysts is investigated, and then catalytic activities of prepared catalysts with different metal compositions on ethylene glycol aqueous-phase reforming are analyzed. The physicochemical properties of the Ni–Al layered hydrotalcite-derived catalysts were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), and nitrogen adsorption–desorption technology. The obtained hydrotalcite-derived catalysts were applied to the process of ethylene glycol aqueous-phase reforming (APR). The XRD results confirmed that the precursors of hydrotalcite-derived catalysts with metal compositions of Ni/Mg/Al, Ni/Cu/Al, Ni/Zn/Al, and Ni/Sn/Al had hydrotalcite crystalloid morphology. During the process of ethylene glycol aqueous phase reforming, all the catalysts showed high conversion of ethylene glycol (>90%), and the optimum hydrogen yield (73.5%) was obtained when using the catalyst with metal composition of Ni/Mg/Al at 225 °C under 2.6 MPa in nitrogen atmosphere for 2.5 h.
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Andrés, Felipe Orrego-Romero, Felipe Arbeláez-Pérez Oscar, Bustamante-Londoño Felipe, and Luz Villa Holguín Aída. "Pelletization of catalysts supported on activated carbon. A Case Study: clean synthesis of dimethyl carbonate from methanol and CO2." Revista Facultad de Ingeniería –redin-, no. 78 (March 19, 2016): 38–47. https://doi.org/10.17533/udea.redin.n78a05.
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The synthesis of Cu-Ni bimetallic catalyst supported on pellets of activated carbon using carboxymethylcellulose (CMC) as a binder is reported. The effect of preparation conditions, such as binder concentration, AC/binder ratio, temperature, and pyrolysis heating rate on the surface area of the pellets, was evaluated. Cu and Ni metals were incorporated on the pellets by conventional incipient wetness impregnation. The support and the synthesized catalysts were characterized using N2 adsorption, H2-TPR, XRD and SEM-EDS techniques. The pelletized catalysts were evaluated for the direct synthesis of dimethyl carbonate DMC (case study). An improved catalytic activity (e.g., ca. 20% increase in conversion) in structured pelletized catalyst in comparison to the powdered catalyst was found.
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Kukushkin, R. G., P. M. Eletskiy, O. A. Bulavchenko, A. A. Saraev, and V. A. Yakovlev. "Studies of the Influence of Promoting the Ni/Al2O3 Catalyst with Copper on the Activity to Hydrotreatment of Esters." Kataliz v promyshlennosti 19, no. 1 (2019): 40–49. http://dx.doi.org/10.18412/1816-0387-2019-1-40-49.
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The influence of the composition of the active component of copper-doped nickel catalysts on the activity and selectivity to hydrodeoxygenation (HDO) of model vegetable oils (esters) to eliminate oxygen and produce alkanes was studied. The Ni/Al2O3 andNi-Cu/Al2O3 catalysts were shown to be active to this process. They catalyzed HDO of a mixture of methyl ester of hexadecane acid and ethyl ester of decane acid to produce C6–C16 alkanes and oxygen-containing compounds, methane and ethane being detected in the gas phase. A decrease in the Ni/Cu ratio in the catalyst led to a decrease in the ester conversion and in the catalyst activity to hydrogenolysis of C–C bonds. Hence, the introduction of copper may favor preservation of the carbon skeleton of HDO-produced alkanes and a decrease in the methane yield. XRD studies revealed the formation of solid solutions Ni1–xCux upon addition of copper to the Ni/Al2O3 catalyst. From XPS data, an increase in the copper proportion in the Ni-Cu/Al2O3 catalyst resulted in a decrease in the Ni/Cu ration on the catalyst surface.
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Popova, Margarita, Ivalina Trendafilova, Manuela Oykova та ін. "Hydrodeoxygenation of Levulinic Acid to γ-Valerolactone over Mesoporous Silica-Supported Cu-Ni Composite Catalysts". Molecules 27, № 17 (2022): 5383. http://dx.doi.org/10.3390/molecules27175383.
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Monometallic (Cu, Ni) and bimetallic (Cu-Ni) catalysts supported on KIT-6 based mesoporous silica/zeolite composites were prepared using the wet impregnation method. The catalysts were characterized using X-ray powder diffraction, N2 physisorption, SEM, solid state NMR and H2-TPR methods. Finely dispersed NiO and CuO were detected after the decomposition of impregnating salt on the silica carrier. The formation of small fractions of ionic Ni2+ and/or Cu2+ species, interacting strongly with the silica supports, was found. The catalysts were studied in the gas-phase upgrading of lignocellulosic biomass-derived levulinic acid (LA) to γ-valerolactone (GVL). The bimetallic, CuNi-KIT-6 catalyst showed 100% LA conversion at 250 °C and atmospheric pressure. The high LA conversion and GVL yield can be attributed to the high specific surface area and finely dispersed Cu-Ni species in the catalyst. Furthermore, the catalyst also exhibited high stability after 24 h of reaction time with a GVL yield above 80% without any significant change in metal dispersion.
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Hartono, Figosstar, Ahmad Suseno, Yayuk Astuti, and Didik Setiyo Widodo. "EFFECT OF CALCINATION TEMPERATURE ON THE PROPERTIES OF SILICA-SUPPORTED Ni-Cu CATALYST FOR THE HYDROCRACKING REACTION OF USED COOKING OIL TO BIOFUEL." Cognizance Journal of Multidisciplinary Studies 3, no. 12 (2023): 21–31. http://dx.doi.org/10.47760/cognizance.2023.v03i12.004.
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The hydrocracking reaction is a reaction that breaks hydrocarbon bonds from vegetable oil into shorter hydrocarbons so that they can be used as biofuel. Ni and Cu metals are quite commonly used in this reaction, where Ni metal functions as an active catalyst in the reaction, and Cu metal plays a role in increasing the stability of Ni metal from coke formation during the hydrocracking reaction. Mesoporous silica is used as a carrier for Ni and Cu metals because it has high stability and porosity. Calcination is one of the processes in the synthesis of mesoporous silica which aims to remove the template from the silica and plays a role in the formation of silica crystallinity and porosity. Changes in calcination temperature will affect the porosity and crystallinity of silica which causes differences in the distribution of Ni and Cu metals. The difference in the distribution of Ni and Cu metals affects the surface area of the active site which can influence the activity and selectivity of the catalyst in the hydrocracking reaction. This research aims to synthesize a Ni-Cu/Silica catalyst for the hydrocracking reaction of used cooking oil into biofuel. Mesoporous silica is synthesized by the hydrothermal method. Then, the Ni-Cu/Silica catalyst was synthesized by impregnating and reducing Ni and Cu metal into mesoporous silica. The Ni-Cu/Silica catalyst was then applied to the used cooking oil hydrocracking reaction to test its activity and selectivity. The results of characterization using FTIR show that the Ni-Cu/Silica catalyst has a vibration peak which indicates the presence of silanol (Si-O-Si) and siloxane (Si-OH) groups. Based on the acidity test, the SM-400, SM-500, and SM-600 catalysts have Lewis acid sites and Brondsted acid sites detected on the FTIR absorption peak with SM-500 having the highest acidity level. The XRD results show that the Ni-Cu/Silica catalyst has amorphous crystallinity and has Ni and Cu metal sites detected in the XRD diffractogram. The GSA results show that the SM-400, SM-500, and SM-600 catalysts have dominant pore sizes in the mesoporous region. The GC-MS results show that hydrocracking using a catalyst produces more product compared to hydrocracking without a catalyst and the SM-500 catalyst has the highest activity and selectivity compared to other variations of catalyst.
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Figosstar, Hartono, Suseno Ahmad, Astuti Yayuk, and Setiyo Widodo Didik. "EFFECT OF CALCINATION TEMPERATURE ON THE PROPERTIES OF SILICA-SUPPORTED Ni-Cu CATALYST FOR THE HYDROCRACKING REACTION OF USED COOKING OIL TO BIOFUEL." Cognizance Journal of Multidisciplinary Studies (CJMS) 3, no. 12 (2023): 21–31. https://doi.org/10.47760/cognizance.2023.v03i12.004.
Full textAbstract:
The hydrocracking reaction is a reaction that breaks hydrocarbon bonds from vegetable oil into shorter hydrocarbons so that they can be used as biofuel. Ni and Cu metals are quite commonly used in this reaction, where Ni metal functions as an active catalyst in the reaction, and Cu metal plays a role in increasing the stability of Ni metal from coke formation during the hydrocracking reaction. Mesoporous silica is used as a carrier for Ni and Cu metals because it has high stability and porosity. Calcination is one of the processes in the synthesis of mesoporous silica which aims to remove the template from the silica and plays a role in the formation of silica crystallinity and porosity. Changes in calcination temperature will affect the porosity and crystallinity of silica which causes differences in the distribution of Ni and Cu metals. The difference in the distribution of Ni and Cu metals affects the surface area of the active site which can influence the activity and selectivity of the catalyst in the hydrocracking reaction. This research aims to synthesize a Ni-Cu/Silica catalyst for the hydrocracking reaction of used cooking oil into biofuel. Mesoporous silica is synthesized by the hydrothermal method. Then, the Ni-Cu/Silica catalyst was synthesized by impregnating and reducing Ni and Cu metal into mesoporous silica. The Ni-Cu/Silica catalyst was then applied to the used cooking oil hydrocracking reaction to test its activity and selectivity. The results of characterization using FTIR show that the Ni-Cu/Silica catalyst has a vibration peak which indicates the presence of silanol (Si-O-Si) and siloxane (Si-OH) groups. Based on the acidity test, the SM-400, SM-500, and SM-600 catalysts have Lewis acid sites and Brondsted acid sites detected on the FTIR absorption peak with SM-500 having the highest acidity level. The XRD results show that the Ni-Cu/Silica catalyst has amorphous crystallinity and has Ni and Cu metal sites detected in the XRD diffractogram. The GSA results show that the SM-400, SM-500, and SM-600 catalysts have dominant pore sizes in the mesoporous region. The GC-MS results show that hydrocracking using a catalyst produces more product compared to hydrocracking without a catalyst and the SM-500 catalyst has the highest activity and selectivity compared to other variations of catalyst.
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Wang, Wenhe, Changsen Zhang, Guanghui Chen, and Ruiqin Zhang. "Influence of CeO2 Addition to Ni–Cu/HZSM-5 Catalysts on Hydrodeoxygenation of Bio-Oil." Applied Sciences 9, no. 6 (2019): 1257. http://dx.doi.org/10.3390/app9061257.
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Hydrodeoxygenation (HDO) of bio-oil is a method of bio-oil upgrading. In this paper, x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) was synthesized as an HDO catalyst by the co-impregnation method. The HDO performances of x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) in the reaction process was evaluated and compared with Ni–Cu/HZSM-5 by the property and the yield of upgrading oil. The difference of the chemical composition between bio-oil and upgrading oil was evaluated by GC-MS. The results showed that the addition of CeO2 decreased the water and oxygen contents of upgrading oil, increased the high heating value, reduced acid content, and increased hydrocarbon content. When the CeO2 addition was 15%, the yield of upgrading reached the maximum, from 33.9 wt% (Ni–Cu/HZSM-5) to 47.6 wt% (15%CeO2–Ni–Cu/HZSM-5). The catalytic activities of x%CeO2–Ni–Cu/HZSM-5 (x = 5, 15, and 20) and Ni–Cu/HZSM-5 were characterized by XRD, N2 adsorption–desorption, NH3-Temperature-Programmed Desorption, H2-Temperature-Programmed Reaction, TEM, and XPS. The results showed that the addition of CeO2 increased the dispersion of active metal Ni, reduced the bond between the active metal and the catalyst support, increased the ratio of Bronsted acid to total acids, and decreased the reduction temperature of NiO. When the CeO2 addition was 15%, the activity of catalyst reached the best. Finally, the carbon deposition resistance of deactivated catalysts was investigated by a Thermogravimetric (TG) analysis, and the results showed that the addition of CeO2 could improve the carbon deposition resistance of catalysts. When the CeO2 addition was 15%, the coke deposition decreased from 41 wt% (Ni–Cu/HZSM-5) to 14 wt% (15%CeO2–Ni–Cu/HZSM-5).
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Wu, Hong Da, Ying Gui Jia, Yu Yin, and Lue Zhao. "Study on the Cu-Ni/Y2O3-ZrO2 Catalytic Performance in Ethanol Steam Reforming." Advanced Materials Research 512-515 (May 2012): 2257–61. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.2257.
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Y2O3-ZrO2 support was prepared by two-step precipitation method with ammonia and oxalic acid. A series of Cu-Ni/Y2O3-ZrO2 catalysts were prepared by impregnation method. The catalysts were investigated and then characterized by XRD and SEM results. The activity of catalysts in ethanol steam reforming was studied. The effects of the catalyst composition on the ethanol conversion rate were discussed and the catalysts inactivation phenomenon under the temperature ranging from 673K to 723K was then analyzed. The results show that 1Cu9Ni/1Y9Zr catalyst has higher activity in ethanol steam reforming, over which ethanol conversion rate is higher than 98% under the situation of 623K, while the inactivation of catalysts with Cu/Ni>3/7 at 673K~723K was caused by carbon deposition .
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Sourav, Sagar, and Israel E. Wachs. "Cr-Free, Cu Promoted Fe Oxide-Based Catalysts for High-Temperature Water-Gas Shift (HT-WGS) Reaction." Catalysts 10, no. 3 (2020): 305. http://dx.doi.org/10.3390/catal10030305.
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Ca, Ni, Co, and Ge promoters were examined as potential candidates to substitute for the current toxic Cr in Cu-promoted Fe oxide-based catalysts for the HT-WGS reaction. The Ca and Ni promoters were found to improve catalyst performance relative to promotion with Cr. The HS-LEIS surface analysis data demonstrate that Ca and Ge tend to segregate on the surface, while Ni, Co, and Cr form solid solutions in the Fe3O4 bulk lattice. The corresponding number of catalytic active sites, redox, and WGS activity values of the catalysts were determined with CO-TPR, CO+H2O-TPSR, and SS-WGS studies, respectively. The poorer HT-WGS performances of the Ge and Co promoters are related to the presence of surface Ge and Co that inhibits catalyst redox ability, with the Co also not stabilizing the surface area of the Fe3O4 support. The Ni promoter uniformly disperses the Cu nanoparticles on the catalyst surface and increases the number of FeOx-Cu interfacial redox sites. The Ca promoter on the catalyst surface, however, enhances the activity of the FeOx-Cu interfacial redox sites. The CO+H2O TPSR results reveal that the redox ability of the active sites follows the SS-WGS performance of the catalysts and show the following trend: 3Cu8CaFe > 3Cu8NiFe ≥ 3Cu8CrFe > 3Cu8CoFe >> 3Cu8GeFe. Furthermore, all the catalysts followed a redox-type reaction mechanism for the HT-WGS reaction.
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Irawan, RM Bagus, Achmad Sholecan, M. Subri, and Antonius Pantomy. "Characterization of Catalytic Converter Made from Chrome-Plated Copper Plate Catalyst for Gasoline Motors." SINTEK JURNAL: Jurnal Ilmiah Teknik Mesin 18, no. 1 (2024): 31–37. https://doi.org/10.24853/sintek.18.1.31-37.
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This study characterizes copper (Cu) and chrome-plated copper (Cu-Cr) catalyst materials used in catalytic converters for gasoline engines. The objective is to investigate morphological and compositional changes resulting from exhaust gas emission testing. Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray Spectroscopy (EDX) was employed for microstructural analysis of the catalyst materials. The research examines morphological changes in Cu and Cu-Cr catalysts before and after exhaust gas emission testing, along with elemental composition alterations. Results indicate that exhaust gas exposure significantly alters the morphology and composition of both catalyst types. Morphologically, Cu catalyst particles originally flat with fine grains exhibited rougher, uneven surfaces with random grain formations and porosity post-testing. Similarly, Cu-Cr catalyst surfaces transformed from smooth to uneven, marked by darkened spots. Compositionally, Cu catalysts initially consisting of five elements (Cu 82.92%, O 5.96%, C 10.22%, Cl 0.60%, Si 0.29%) changed to include eight elements (Cu 70.65%, O 12.89%, C 12.85%, Cl 0.66%, Si 0.27%, N 1.74%, Al 0.27%, S 0.67%). Cu-Cr catalysts initially composed of three elements (Ni 87.65%, Cr 10.50%, C 1.85%) evolved to five elements (Ni 86.01%, Cr 6.56%, O 5.70%, O 1.42%, S 0.71%). These findings underscore the transformative effects of exhaust gas exposure on catalyst materials, influencing both their morphology and elemental composition, crucial for enhancing catalytic converter performance and durability in automotive applications.
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Torres, Daniel, José Pinilla, and Isabel Suelves. "Co-, Cu- and Fe-Doped Ni/Al2O3 Catalysts for the Catalytic Decomposition of Methane into Hydrogen and Carbon Nanofibers." Catalysts 8, no. 8 (2018): 300. http://dx.doi.org/10.3390/catal8080300.
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The catalytic decomposition of methane (CDM) process produces hydrogen in a single stage and avoids CO2 emission thanks to the formation of high added value carbon nanofilaments as a by-product. In this work, Ni monometallic and Ni–Co, Ni–Cu, and Ni–Fe bimetallic catalysts are tested in the CDM reaction for the obtention of fishbone carbon nanofibers (CNF). Catalysts, in which Al2O3 is used as textural promoter in their formulation, are based on Ni as main active phase for the carbon formation and on Co, Cu, or Fe as dopants in order to obtain alloys with improved catalytic behaviour. Characterization of bimetallic catalysts showed the formation of particles of Ni alloys with a bimodal size distribution. For the doping content studied (5 mol. %), only Cu formed an alloy with a lattice constant high enough to be able to favor the carbon diffusion through the catalytic particle against surface diffusion, resulting in higher carbon formations, longer activity times, and activity at 750 °C; whereas Ni, Ni–Co, and Ni–Fe catalysts were inactive. On the other hand, Fe also improved the undoped catalyst performance presenting a higher carbon formation at 700 °C and the obtention of narrow carbon nanofilaments from active Ni3Fe crystallites.
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Matos, Juan, and Maibelin Rosales. "Promoter Effect upon Activated Carbon-Supported Ni-Based Catalysts in Dry Methane Reforming." Eurasian Chemico-Technological Journal 14, no. 1 (2011): 5. http://dx.doi.org/10.18321/ectj91.
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<p>The influence of selected promoters such as Ca, Mg, Cu and Zn upon activated carbon-supported Ni-based catalysts in the dry methane reforming under mild experimental conditions (650 ºC, 1 atm) was verified. It was found that Ni-Mg catalyst showed the highest initial catalytic activity followed by NiCa/AC catalyst. As expected, catalysts promoted with the most basic oxides such as MgO or CaO showed moderate deactivation after 4 h reaction ascribed to the basic Lewis behaviour which stabilize Ni-based catalysts.</p>
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Dyer, Andrew C., Mohamad A. Nahil, and Paul T. Williams. "Biomass:polystyrene co-pyrolysis coupled with metal-modified zeolite catalysis for liquid fuel and chemical production." Journal of Material Cycles and Waste Management 24, no. 2 (2022): 477–90. http://dx.doi.org/10.1007/s10163-021-01334-0.
Full textAbstract:
AbstractBiomass and waste polystyrene plastic (ratio 1:1) were co-pyrolysed followed by catalysis in a two-stage fixed bed reactor system to produce upgraded bio-oils for production of liquid fuel and aromatic chemicals. The catalysts investigated were ZSM-5 impregnated with different metals, Ga, Co, Cu, Fe and Ni to determine their influence on bio-oil upgrading. The results showed that the different added metals had a different impact on the yield and composition of the product oils and gases. Deoxygenation of the bio-oils was mainly via formation of CO2 and CO via decarboxylation and decarbonylation with the Ni–ZSM-5 and Co–ZSM-5 catalysts whereas higher water yield and lower CO2 and CO was obtained with the ZSM-5, Ga–ZSM-5, Cu–ZSM-5 and Fe–ZSM-5 catalysts suggesting hydrodeoxygenation was dominant. Compared to the unmodified ZSM-5, the yield of single-ring aromatic compounds in the product oil was increased for the Co–ZSM-5, Cu–ZSM-5, Fe–ZSM-5 and Ni–ZSM-5 catalysts. However, for the Ga–ZSM-5 catalyst, single-ring aromatic compounds were reduced, but the highest yield of polycyclic aromatic hydrocarbons was produced. A higher biomass to polystyrene ratio (4:1) resulted in a markedly lower oil yield with a consequent increased yield of gas.
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Bergamaschi, V. S., and F. M. S. Carvalho. "Hydrogen Production by Ethanol Steam Reforming Over Cu and Ni Catalysts Supported on ZrO2 and Al2O3 Microspheres." Materials Science Forum 591-593 (August 2008): 734–39. http://dx.doi.org/10.4028/www.scientific.net/msf.591-593.734.
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Ethanol reforming process to produce hydrogen rich-gas stream is performed using Cu/Ni catalyst supported on zirconia and alumina microspheres prepared by hydrolysis method. Theses catalysts were tested in a fixed-bed reactor system employing steam reforming of ethanol. The operating temperature was 550°C and water/ethanol feed ratio 3/1. Although all catalysts were very active for ethanol conversion and very selective towards the desired products, but that one supported on zirconia microspheres was produced slightly better results. The data reveal high activity of the Cu/Ni/ZrO2 catalyst for ethanol steam reforming and presented a good selectivity for H2.
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Osti, Andrea, Lorenzo Rizzato, Jonathan Cavazzani, Ambra Meneghello, and Antonella Glisenti. "Perovskite Oxide Catalysts for Enhanced CO2 Reduction: Embroidering Surface Decoration with Ni and Cu Nanoparticles." Catalysts 14, no. 5 (2024): 313. http://dx.doi.org/10.3390/catal14050313.
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The imperative reduction of carbon dioxide into valuable fuels stands as a crucial step in the transition towards a more sustainable energy system. Perovskite oxides, with their high compositional and property adjustability, emerge as promising catalysts for this purpose, whether employed independently or as a supporting matrix for other active metals. In this study, an A-site-deficient La0.9FeO3 perovskite underwent surface decoration with Ni, Cu or Ni + Cu via a citric acid-templated wet impregnation method. Following extensive characterization through XRD, N2 physisorption, H2-TPR, SEM-EDX, HAADF STEM-EDX mapping, CO2-TPD and XPS, the prepared powders underwent reduction under diluted H2 to yield metallic nanoparticles (NPs). The prepared catalysts were then evaluated for CO2 reduction in a CO2/H2 = 1/4 mixture. The deposition of Ni or Cu NPs on the perovskite support significantly enhanced the conversion of CO2, achieving a 50% conversion rate at 500 °C, albeit resulting in only CO as the final product. Notably, the catalyst featuring Ni-Cu co-deposition outperformed in the intermediate temperature range, exhibiting high selectivity for CH4 production around 350 °C. For this latter catalyst, a synergistic effect of the metal–support interaction was evidenced by H2-TPR and CO2-TPD experiments as well as a better nanoparticle dispersion. A remarkable stability in a 20 h time-span was also demonstrated for all catalysts, especially the one with Ni-Cu co-deposition.
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Xue, Huiyuan, Xingxing Gong, Jingjing Xu, and Rongrong Hu. "Performance of a Ni-Cu-Co/Al2O3 Catalyst on in-situ Hydrodeoxygenation of Bio-derived Phenol." Catalysts 9, no. 11 (2019): 952. http://dx.doi.org/10.3390/catal9110952.
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The in-situ hydrodeoxygenation of bio-derived phenol is an attractive routine for upgrading bio-oils. Herein, an active trimetallic Ni-Cu-Co/Al2O3 catalyst was prepared and applied in the in-situ hydrodeoxygenation of bio-derived phenol. Comparison with the monometallic Ni/Al2O3 catalyst and the bimetallic Ni-Co/Al2O3 and Ni-Cu/Al2O3 catalysts, the Ni-Cu-Co/Al2O3 catalyst exhibited the highest catalytic activity because of the formation of Ni-Cu-Co alloy on the catalyst characterized by using X-ray powder diffraction (XRD), temperature programmed reduction (TPR), N2 physisorption, scanning electron microscope (SEM), and transmission electron microscope (TEM). The phenol conversion of 100% and the cyclohexane yield of 98.3% could be achieved in the in-situ hydrodeoxygenation of phenol at 240 °C and 4 MPa N2 for 6 h. The synergistic effects of Ni with Cu and Co of the trimetallic Ni-Cu-Co/Al2O3 catalyst played a significant role in the in-situ hydrodeoxygenation process of phenol, which not only had a positive effect on the production of hydrogen but also owned an excellent hydrogenolysis activity to accelerate the conversion of cyclohexanol to cyclohexane. Furthermore, the catalyst also exhibited excellent recyclability and good potential for the upgrading of bio-oils.
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Liu, Guimei, and Minhua Shao. "(Invited) Efficient Ternary Nicuw Hydrogen Oxidation Catalysts for Anion Exchange Membrane Fuel Cells." ECS Meeting Abstracts MA2024-01, no. 36 (2024): 2037. http://dx.doi.org/10.1149/ma2024-01362037mtgabs.
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Anion exchange membrane fuel cells (AEMFCs) offer prospective approaches to replace proton exchange membrane fuel cells via cost-effective catalysts and membranes. While significant progress has been made in efficient nonnoble electrocatalysts for oxygen reduction reaction in alkaline media, the hydrogen oxidation reaction (HOR) in the alkaline condition still relies on high platinum loadings to compensate for its sluggish kinetics. Therefore, developing efficient non-noble metal electrocatalysts with Pt-like HOR performances in alkaline electrolytes is highly desired but a great challenge. The hydrogen binding energy (HBE) has been identified as the primary descriptor for the HOR. Additionally, an unfavorable hydroxide binding energy (OHBE) is considered the rate-determining step in the Volmer reaction to generate water. Therefore, an ideal catalyst for HOR should achieve a balance between HBE and OHBE. However, despite being a promising non-noble metal, nickel exhibits excessively high HBE and lacks active sites for hydroxide adsorption, which hinders its further application in the real fuel cell. In this work, NiW was successfully deposited onto Cu to form a ternary Ni-Cu-W alloy catalyst by a chemical reduction method. Through XPS spectra, we found the charge transfer from Ni to W to give Ni a higher valence state, contributing to a weakened hydrogen binding energy. Electrochemical measurements observed Ni-Cu-W exhibit an kinetic activity with 117.9 mA/mgNi at η= 50 mV, which is the highest among the reported platinum group metal-free catalysts. Ni-Cu-W alloy showcased robust stability, with no activity degradation during an accelerated long-term durability test between a low overpotential (-0.1 ~ 0.1 V, vs RHE) with 10,000 cyclic voltammetry scans and only a 5.7% activity loss at η= 50 mV when applying more larger overpotential (-0.1 ~ 0.2 V) with the same cycles. When assembled with this catalyst as anode and Pt/C as cathode, it delivered a peak power density of 289 mW/cm2. Both experimental and theoretical studies were conducted to gain insights into the catalyst's enhanced performance. Our findings revealed that the incorporation of Cu into the catalyst significantly weakened the adsorption of hydrogen species, while simultaneously lowering the energy barrier required for the absorption of hydroxide ions. These key observations might shed light on the underlying mechanisms responsible for the catalyst's improved activity and stability.
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Zhou, Shuzhen, Lihua Kang, Xuening Zhou, Zhu Xu, and Mingyuan Zhu. "Pure Acetylene Semihydrogenation over Ni–Cu Bimetallic Catalysts: Effect of the Cu/Ni Ratio on Catalytic Performance." Nanomaterials 10, no. 3 (2020): 509. http://dx.doi.org/10.3390/nano10030509.
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Ethylene is an important chemical raw material and with the increasing consumption of petroleum resources, the production of ethylene through the calcium carbide acetylene route has important research significance. In this work, a series of bimetallic catalysts with different Cu/Ni molar ratios are prepared by co-impregnation method for the hydrogenation of calcium carbide acetylene to ethylene. The introduction of an appropriate amount of Cu effectively inhibits not only the formation of ethane and green oil, thus increasing the selectivity of ethylene, but also the formation of carbon deposits, which improves the stability of the catalyst. The ethylene selectivity of the Ni–Cu bimetallic catalyst increases from 45% to 63% compared with the Ni monometallic counterpart and the acetylene conversion still can reach 100% at the optimal conditions of 250 °C, 8000 mL·g−1·h−1 and V(H2)/V(C2H2) = 3. X-ray diffraction and transmission electron microscopy confirmed that the metal particles were highly dispersed on the support, High-resolution transmission electron microscopy and H2-Temperature programmed reduction proved that there was an interaction between Ni and Cu, combined with X-ray photoelectron spectroscopy and density functional theory calculations results, Cu transferred electrons to Ni changed the Ni electron cloud density in NiCux catalysts, thus reducing the adsorption of acetylene and ethylene, which is favorable to ethylene selectivity.
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Alves, Carine T., and Jude A. Onwudili. "Screening of Nickel and Platinum Catalysts for Glycerol Conversion to Gas Products in Hydrothermal Media." Energies 15, no. 20 (2022): 7571. http://dx.doi.org/10.3390/en15207571.
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The production of low-carbon gaseous fuels from biomass has the potential to reduce greenhouse gas emissions and promote energy sustainability, stability and affordability around the world. Glycerol, a large-volume by-product of biodiesel production, is a potential feedstock for the production of low-carbon energy vectors. In this present work, an aqueous solution of pure glycerol was reacted under hydrothermal conditions using a total of 10 types of heterogeneous catalysts to evaluate its conversion to gas products (hydrogen, methane, CO, CO2 and C2–C4 hydrocarbon gases). Two bimetallic Ni-Fe and Ni-Cu catalysts, three Pt-based catalysts and physical mixtures of the five catalysts were tested. The reactions were carried out in a batch reactor for 1 h reaction time, using a 9:1 mass ratio of water/glycerol (10 wt%) and the reaction temperatures ranged between 250–350 °C using and without using 1 g of catalyst. The effects of the catalysts and reaction conditions on the conversion of glycerol in terms of carbon and hydrogen gasification efficiencies, selectivity and yields of components in the gas products were investigated. CO2 remained the most dominant gas product in all experiments. The results indicated that increasing the reaction temperature favoured gas formation and both carbon and hydrogen gasification efficiencies. The combination of Ni-Cu and Pt/C catalysts was the most selective catalyst for gas formation at 350 °C, giving carbon gasification efficiency of 95.6 wt%. Individually, the catalyst with the highest hydrogen production was Pt/C and the highest propane yield was obtained with the Ni-Cu bimetallic catalyst. Some catalysts showed good structural stability in hydrothermal media but need improvements towards better yields of desired fuel gases.
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Susmanto, Prahady, Ambo Intang, Muhammad Djoni Bustan, and Sri Haryati. "Effect of metal addition of Cu, Ni, and Fe on swelling Zeolit Alam Lampung (ZAL) to present amphoteric features on Cu-Ni-Fe/ZAL swelling." Polish Journal of Chemical Technology 26, no. 4 (2024): 8–16. https://doi.org/10.2478/pjct-2024-0034.
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Abstract The main challenge in using Zeolit Alam Lampung (ZAL) as a catalyst lies in controlling its acidic nature which is influenced by the content of alkali metals, alkaline earth metals, transition metals, and Si/Al ratio. Controlling by reducing and adding metals with higher acidity is necessary. This research involved two stages: ZAL Swelling formation followed by adding Cu, Ni, and Fe metals to make a Cu-Ni-Fe/ZAL Swelling catalyst. The acid distribution analysis using the NH3-TPD profile test showed that the Cu-Ni-Fe/ZAL swelling catalyst exhibited higher Lewis-type acidity and more uniform distribution compared to Brønsted acid. The addition of Cu, Ni, and Fe metals can modify the acidity strength of ZAL Swelling to form Cu-Ni-Fe/ZAL Swelling catalysts with Lewis and Brønsted sites at lower temperatures (120–550 °C) compared to ZAL Swelling (120–750 °C). This gives an idea about the optimization of the arrangement of Lewis and Bronsted acid sites to present amphoteric features.
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Silva, Gisele C. R., Dali Qian, Robert Pace, et al. "Promotional Effect of Cu, Fe and Pt on the Performance of Ni/Al2O3 in the Deoxygenation of Used Cooking Oil to Fuel-Like Hydrocarbons." Catalysts 10, no. 1 (2020): 91. http://dx.doi.org/10.3390/catal10010091.
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Inexpensive Ni-based catalysts can afford comparable performance to costly precious metal formulations in the conversion of fat, oil, or greases (FOG) to fuel-like hydrocarbons via decarboxylation/decarbonylation (deCOx). While the addition of certain metals has been observed to promote Ni-based deCOx catalysts, the steady-state performance of bimetallic formulations must be ascertained using industrially relevant feeds and reaction conditions in order to make meaningful comparisons. In the present work, used cooking oil (UCO) was upgraded to renewable diesel via deCOx over Ni/Al2O3 promoted with Cu, Fe, or Pt in a fixed-bed reactor at 375 °C using a weight hourly space velocity (WHSV) of 1 h−1. Although all catalysts fully deoxygenated the feed to hydrocarbons throughout the entire 76 h duration of these experiments, the cracking activity (and the evolution thereof) was distinct for each formulation. Indeed, that of the Ni-Cu catalyst was low and relatively stable, that of the Ni-Fe formulation was initially high but progressively dropped to become negligible, and that of the Ni-Pt catalyst started as moderate, varied considerably, and finished high. Analysis of the spent catalysts suggests that the evolution of the cracking activity can be mainly ascribed to changes in the composition of the metal particles.
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Yao, Yunxi, and D. Wayne Goodman. "New insights into structure–activity relationships for propane hydrogenolysis over Ni–Cu bimetallic catalysts." RSC Advances 5, no. 54 (2015): 43547–51. http://dx.doi.org/10.1039/c5ra07433a.
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Nikolaev, S. A., D. I. Ezzhelenko, A. V. Chistyakov, P. A. Chistyakova, and M. V. Tsodikov. "Influence of Synthesis Conditions on the Performance of Palladium–Copper Ethanol-to-Butanol Conversion Catalysts." Нефтехимия 63, no. 4 (2023): 566–81. http://dx.doi.org/10.31857/s0028242123040111.
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The influence of the synthesis conditions on the performance of Pd–Cu ethanol-to-butanol conversion catalysts was studied. The optimum conditions for forming the most active system 0.2%Cu/0.3%Pd/Al2O3 are as follows: sample synthesis by Al2O3 impregnation from aqueous solutions of Pd and Cu nitrates; deposition of the metal precursors in succession; total content of Pd and Cu in the sample 0.5 wt %; Pd : Сu molar ratio 1 : 1; catalyst reduction temperature 200○С. As shown by TEM, XPS, TPD-NH3, TPR-H2, XRD, and N2 adsorption, the surface of the most active catalyst contains Pd0Cu0 particles with the mean size of 4 ± 2 nm. The bimetallic particles are an alloy with the fcc structure and Pd : Cu ratio of 40 : 60. At 275○C, the performance of 0.2%Cu/0.3%Pd/Al2O3 is 182 × 10–4 mol h–1 g–1. The value obtained is higher by several orders of magnitude than the performance of the reference catalysts M1/Al2O3 (M1 = Fe, Ni, Co) and by an order of magnitude than that of the reference catalysts M2/Al2O3 (M2 = Ru, Rh, Pt, Pd, Pt–Re, Ni–Mo).
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Yun, Hafizah Abdul Halim, Ramli Mat, Tuan Amran Tuan Abdullah, Mahadhir Mohamed, and Anwar Johariand Asmadi Ali. "Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen." Applied Mechanics and Materials 699 (November 2014): 504–9. http://dx.doi.org/10.4028/www.scientific.net/amm.699.504.
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The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.