Journal articles: 'Activated carbon supported metal oxide catalyst'

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Thangadurai, Tavayogeshwary, and Ching Thian Tye. "Performance of Activated Carbon Supported Cobalt Oxides and Iron Oxide Catalysts in Catalytic Cracking of Waste Cooking Oil." Periodica Polytechnica Chemical Engineering 65, no. 3 (May 13, 2021): 350–60. http://dx.doi.org/10.3311/ppch.16885.

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This work studied the catalyst activity of activated carbon (AC) supported Co, Fe and Co-Fe oxides in catalytic cracking of waste cooking oil. Reactions were carried out in a fixed bed reactor at 450 °C with WHSV 9 hr–1. Single metal Co/AC and Fe/AC catalysts with different metal loading (2.5–15 wt.%) and bimetal xCo-yFe/AC (x, y = 2.5 to 12.5 wt.%; x + y =15 wt.%) catalysts were investigated. Co/AC and Fe/AC catalysts both contributed to significant liquid yield with high selectivity towards C15 and C17 hydrocarbons. Fe/AC catalysts gave high C5 – C20 hydrocarbon yield whereas Co/AC attained more palmitic (C16) and oleic (C18) acid conversion. Synergistic effect in two metals Co-Fe/AC catalysts had further improved the liquid hydrocarbon yield (up to ~93 %) and fatty acid conversion (up to 94 %). The best catalyst, 10Co-5Fe/AC had been further tested under the effect of reaction temperature, feed flow rate (WHSV) and deactivation for its catalytic performance.

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Rusanen, Annu, Riikka Kupila, Katja Lappalainen, Johanna Kärkkäinen, Tao Hu, and Ulla Lassi. "Conversion of Xylose to Furfural over Lignin-Based Activated Carbon-Supported Iron Catalysts." Catalysts 10, no. 8 (July 22, 2020): 821. http://dx.doi.org/10.3390/catal10080821.

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In this study, conversion of xylose to furfural was studied using lignin-based activated carbon-supported iron catalysts. First, three activated carbon supports were prepared from hydrolysis lignin with different activation methods. The supports were modified with different metal precursors and metal concentrations into five iron catalysts. The prepared catalysts were studied in furfural production from xylose using different reaction temperatures and times. The best results were achieved with a 4 wt% iron-containing catalyst, 5Fe-ACs, which produced a 57% furfural yield, 92% xylose conversion and 65% reaction selectivity at 170 °C in 3 h. The amount of Fe in 5Fe-ACs was only 3.6 µmol and using this amount of homogeneous FeCl3 as a catalyst, reduced the furfural yield, xylose conversion and selectivity. Good catalytic activity of 5Fe-ACs could be associated with iron oxide and hydroxyl groups on the catalyst surface. Based on the recycling experiments, the prepared catalyst needs some improvements to increase its stability but it is a feasible alternative to homogeneous FeCl3.

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Liu, Fang, Li Yang, Jie Cheng, Xin Wu, Wenbin Quan, and Kozo Saito. "Low Temperature deNOx Catalytic Activity with C2H4 as a Reductant Using Mixed Metal Fe-Mn Oxides Supported on Activated Carbon." Energies 12, no. 22 (November 14, 2019): 4341. http://dx.doi.org/10.3390/en12224341.

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The selective catalytic reduction of NOx (deNOx) at temperatures less than or at 200 °C was investigated while using C2H4 as the reductant and mixed oxides of Fe and Mn supported on activated carbon; their activity was compared to that of MnOx and FeOx separately supported on activated carbon. The bimetallic oxide compositions maintained high NO conversion of greater than 80–98% for periods that were three times greater than those of the supported monometallic oxides. To examine potential reasons for the significant increases in activity maintenance, and subsequent deactivation, the catalysts were examined by using bulk and surface sensitive analytical techniques before and after catalyst testing. No significant changes in Brunauer-Emmett-Teller (BET) surface areas or porosities were observed between freshly-prepared and tested catalysts whereas segregation of FeOx and MnOx species was readily observed in the mono-oxide catalysts after reaction testing that was not detected in the mixed oxide catalysts. Furthermore, x-ray diffraction and Raman spectroscopy data detected cubic Fe3Mn3O8 in both the freshly-prepared and reaction-tested mixed oxide catalysts that were more crystalline after testing. The presence of this compound, which is known to stabilize multivalent Fe species and to enhance oxygen transfer reactions, may be the reason for the high and relatively stable NO conversion activity, and its increased crystallinity during longer-term testing may also decrease surface availability of the active sites responsible for NO conversion. These results point to a potential of further enhancing catalyst stability and activity for low temperature deNOx that is applicable to advanced SCR processing with lower costs and less deleterious side effects to processing equipment.

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Luo, Mingsheng, Shuo Li, Zuoxing Di, He Li, Qinglong Liu, Baozhong Lü, Aimei Wang, Buchang Shi, and Iltaf Khan. "Fischer–Tropsch Synthesis: Study of Different Carbon Materials as Cobalt Catalyst Support." Reactions 2, no. 1 (March 10, 2021): 43–61. http://dx.doi.org/10.3390/reactions2010005.

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In this work, cobalt Fischer–Tropsch synthesis (FTS) catalyst supported on various carbon materials, i.e., carbon nanotube (CNT), activated carbon (AC), graphene oxide (GO), reduced graphene oxide (rGO), and carbon nanofiber (CNF), were prepared via impregnation method. Based on TGA, nitrogen physisorption, XRD, Raman spectroscopy, H2-TPR, NH3-TPD, ICP, SEM, and TEM characterization, it is confirmed that Co3O4 particles are dispersed uniformly on the supports of carbon nanotube, activated carbon and carbon nanofiber. Furthermore, the FT catalyst performance for as-prepared catalysts was evaluated in a fixed-bed reactor under the condition of H2:CO = 2:1, 5 SL·h−1·g−1, 2.5 MPa, and 210 °C. Interestingly, the defined three types of carbon materials exhibit superior performance and dispersion compared with graphene oxide and reduced graphene oxide. The thermal stability and pore structure of the five carbon materials vary markedly, and H2-TPR result shows that the metal–support interaction is in the order of Co/GO > Co/CNT > Co/AC > Co/CNF > Co/rGO. In brief, the carbon nanofiber-supported cobalt catalyst showed the best dispersion, the highest CO conversion, and the lowest gas product but the highest heavy hydrocarbons (C5+) selectivity, which can be attributed to the intrinsic property of CNF material that can affect the catalytic performance in a complicated way. This work will open up a new gateway for cobalt support catalysts on various carbon-based materials for Fischer–Tropsch Synthesis.

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Cao, Wan, and Weijun Zhang. "Low temperature selective catalytic reduction of nitric oxide with an activated carbon-supported zero-valent iron catalyst." RSC Advances 10, no. 69 (2020): 42613–18. http://dx.doi.org/10.1039/d0ra07939a.

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Pudi, Satyanarayana Murty, Tarak Mondal, Prakash Biswas, Shalini Biswas, and 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, no. 1 (January 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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Chornaja, Svetlana, Elina Sproge, Konstantins Dubencovs, Lidija Kulikova, Vera Serga, Antons Cvetkovs, and Valdis Kampars. "Selective Oxidation of Glycerol to Glyceraldehyde over Novel Monometallic Platinum Catalysts." Key Engineering Materials 604 (March 2014): 138–41. http://dx.doi.org/10.4028/www.scientific.net/kem.604.138.

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Several novel monometallic platinum catalysts supported on metal oxides (Al2O3, Y2O3, γ-Al2O3, Lu2O3, ZrO2-Y2O3 TiO2, SiO2, γ-AlO(OH)) and activated carbon (C) were synthesized by extractive-pyrolytic method and tested in glycerol oxidation processes without base addition to obtain glyceraldehyde. It was found that Pt catalyst activity is strongly influenced by support nature, oxygen partial pressure and Pt loading. Pt/Al2O3 and Pt/SiO2 catalysts exhibited the highest activity but selectivity to glyceraldehyde significantly decreased when glycerol conversion increased.

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Gamal, Ahmed, Kamel Eid, Muftah H. El-Naas, Dharmesh Kumar, and Anand Kumar. "Catalytic Methane Decomposition to Carbon Nanostructures and COx-Free Hydrogen: A Mini-Review." Nanomaterials 11, no. 5 (May 6, 2021): 1226. http://dx.doi.org/10.3390/nano11051226.

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Catalytic methane decomposition (CMD) is a highly promising approach for the rational production of relatively COx-free hydrogen and carbon nanostructures, which are both important in multidisciplinary catalytic applications, electronics, fuel cells, etc. Research on CMD has been expanding in recent years with more than 2000 studies in the last five years alone. It is therefore a daunting task to provide a timely update on recent advances in the CMD process, related catalysis, kinetics, and reaction products. This mini-review emphasizes recent studies on the CMD process investigating self-standing/supported metal-based catalysts (e.g., Fe, Ni, Co, and Cu), metal oxide supports (e.g., SiO2, Al2O3, and TiO2), and carbon-based catalysts (e.g., carbon blacks, carbon nanotubes, and activated carbons) alongside their parameters supported with various examples, schematics, and comparison tables. In addition, the review examines the effect of a catalyst’s shape and composition on CMD activity, stability, and products. It also attempts to bridge the gap between research and practical utilization of the CMD process and its future prospects.

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Ferreiro, Cristian, Natalia Villota, José Ignacio Lombraña, María J. Rivero, Verónica Zúñiga, and José Miguel Rituerto. "Removal of Aniline and Benzothiazole Wastewaters Using an Efficient MnO2/GAC Catalyst in a Photocatalytic Fluidised Bed Reactor." Materials 14, no. 18 (September 10, 2021): 5207. http://dx.doi.org/10.3390/ma14185207.

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This work presents an efficient method for treating industrial wastewater containing aniline and benzothiazole, which are refractory to conventional treatments. A combination of heterogeneous photocatalysis operating in a fluidised bed reactor is studied in order to increase mass transfer and reduce reaction times. This process uses a manganese dioxide catalyst supported on granular activated carbon with environmentally friendly characteristics. The manganese dioxide composite is prepared by hydrothermal synthesis on carbon Hydrodarco® 3000 with different active phase ratios. The support, the metal oxide, and the composite are characterised by performing Brunauer, Emmett, and Teller analysis, transmission electron microscopy, X-ray diffraction analysis, X-ray fluorescence analysis, UV–Vis spectroscopy by diffuse reflectance, and Fourier transform infrared spectroscopy in order to evaluate the influence of the metal oxide on the activated carbon. A composite of MnO2/GAC (3.78% in phase α-MnO2) is obtained, with a 9.4% increase in the specific surface of the initial GAC and a 12.79 nm crystal size. The effect of pH and catalyst load is studied. At a pH of 9.0 and a dose of 0.9 g L−1, a high degradation of aniline and benzothiazole is obtained, with an 81.63% TOC mineralisation in 64.8 min.

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Kupila, Riikka, Katja Lappalainen, Tao Hu, Henrik Romar, and Ulla Lassi. "Lignin-based activated carbon-supported metal oxide catalysts in lactic acid production from glucose." Applied Catalysis A: General 612 (February 2021): 118011. http://dx.doi.org/10.1016/j.apcata.2021.118011.

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Liu, Kaijie, Qingbo Yu, Baolan Wang, Qin Qin, Mengqi Wei, and Qi Fu. "Low temperature selective catalytic reduction of nitric oxide with urea over activated carbon supported metal oxide catalysts." Environmental Technology 41, no. 7 (September 6, 2018): 808–21. http://dx.doi.org/10.1080/09593330.2018.1511752.

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Bilińska, Lucyna, Kazimierz Blus, Magdalena Bilińska, and Marta Gmurek. "Industrial Textile Wastewater Ozone Treatment: Catalyst Selection." Catalysts 10, no. 6 (June 1, 2020): 611. http://dx.doi.org/10.3390/catal10060611.

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One of the recent trends in textile wastewater treatment has become catalytic ozonation. The necessity of effective color removal in a short treatment time is a standard during industrial implementation. At the same time, efficient chemical oxygen demand (COD), total organic carbon (TOC), and toxic by-product removal are highly expected. This study presents the results of a catalytic ozonation treatment. Three types of catalysts: a metal oxide (TiO2 as P25 by Degussa), activated carbon (nano-powder by Sigma, AC), and metal particles (platinum, 1% wt. supported on AC matrix by Sigma, Pt–AC) have been applied. The investigations were conducted for real industrial wastewater originated in textile dyeing with Reactive Black 5 dye (RB5). The experiments ran for the raw wastewater (without pretreatment), exposed blocking of the catalytic action by all used catalysts. The catalytic effect could be observed when catalytic ozonation was used as a polishing step after electrocoagulation (EC). Although the catalytic effect could be observe for all catalysts then, especially in the removal of colorless by-products, the AC was exposed as the most effective. This contributed to 35% and 40% of TOC and COD removal. While only 18% and 23% of TOC and COD were removed in the same process without AC. The decrease in toxicity was 30%. The results of the study revealed the complexity of the issue and resulted in an extensive discussion devoted to the basis of the catalytic activity of each catalyst.

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Costa de Oliveira, Maida Aysla, Alessandra D’Epifanio, Hitoshi Ohnuki, and Barbara Mecheri. "Platinum Group Metal-Free Catalysts for Oxygen Reduction Reaction: Applications in Microbial Fuel Cells." Catalysts 10, no. 5 (April 26, 2020): 475. http://dx.doi.org/10.3390/catal10050475.

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Scientific and technological innovation is increasingly playing a role for promoting the transition towards a circular economy and sustainable development. Thanks to its dual function of harvesting energy from waste and cleaning up waste from organic pollutants, microbial fuel cells (MFCs) provide a revolutionary answer to the global environmental challenges. Yet, one key factor that limits the implementation of larger scale MFCs is the high cost and low durability of current electrode materials, owing to the use of platinum at the cathode side. To address this issue, the scientific community has devoted its research efforts for identifying innovative and low cost materials and components to assemble lab-scale MFC prototypes, fed with wastewaters of different nature. This review work summarizes the state-of the-art of developing platinum group metal-free (PGM-free) catalysts for applications at the cathode side of MFCs. We address how different catalyst families boost oxygen reduction reaction (ORR) in neutral pH, as result of an interplay between surface chemistry and morphology on the efficiency of ORR active sites. We particularly review the properties, performance, and applicability of metal-free carbon-based materials, molecular catalysts based on metal macrocycles supported on carbon nanostructures, M-N-C catalysts activated via pyrolysis, metal oxide-based catalysts, and enzyme catalysts. We finally discuss recent progress on MFC cathode design, providing a guidance for improving cathode activity and stability under MFC operating conditions.

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Wang, Shaobin, and G. Q. (Max) Lu. "Effects of Oxide Promoters on Metal Dispersion and Metal−Support Interactions in Ni Catalysts Supported on Activated Carbon." Industrial & Engineering Chemistry Research 36, no. 12 (December 1997): 5103–9. http://dx.doi.org/10.1021/ie9703604.

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Liu, Rong, Yi Fan Xu, Fei Ye, Ling Chen Ji, Hao Guan, and Ming Yang. "Low-Temperature Selective Catalytic Reduction with NH₃ over MnO_x-CeO₂ Catalysts Supported on Nano Tetragonal Zirconia." Materials Science Forum 852 (April 2016): 293–99. http://dx.doi.org/10.4028/www.scientific.net/msf.852.293.

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The MnOx-CeO2/t-ZrO2 catalyst was prepared by impregnation with nano t-ZrO2 as the support. The influence of active component and reaction temperature on denitration performance of catalyst was investigated. The results showed that denitration efficiency improved as active component increased and reaction temperature rose. The denitration efficiency of 2.5% MnOx-CeO2/t-ZrO2 at 100°C was 68.1% while 15% MnOx-CeO2/t-ZrO2 was 97.4%. The results of XRD, BET and H2-TPR showed that surface structure of loaded catalyst was good for oxidation-reduction and denigration. NH3-TPD test demonstrated that NH3 was mainly adsorbed at Lewis acid sites on the surface of catalysts and became coordination NH3. Intermediate product NH2NO generated from reactions between coordination NH3 and NO which finally changed into N2 and H2O.NOx are potentially harmful to humans as a kind of primary pollutants. And NOx are the main cause of many environment problems, such as acid rain, surface ozone pollution and Particulate Matter 2.5[1]. The emission of NOx was 2337.8 tons in China in 2011 and that was 2275.4 tons[2]. The environmental situation is grim although the emission of NOx had begun decreasing. Emission standard of air pollutants for thermal power plants which came into effect on January 1, 2012 require the emission concentration of NOx under 100mg·m-3. The task is arduous.Selective catalytic reduction (SCR) of NOx with NH3 is the most promising method to remove NOx and catalysts with high activity play a decisive part in low temperature SCR technology. Many researches about metal oxide as SCR catalyst support have been reported recently, such as TiO2[3], Al2O3[4], activated carbon[5] and molecular sieve[6]. Zirconium oxide has attracted considerable attention recently as a catalyst support because of its special characteristics. Takahashi et al.[7] investigated the influence of the various compositions of TiO2 and ZrO2 on the NOx removal ability over a sulfur-treated NSR catalyst and came to a conclusion that ZrO2 support suppressed the solid phase reaction with potassium. Reddy et al.[8, 9] investigated structural characteristics of nanosized ceria-silica, ceria-titania, and ceria-zirconia mixed oxide catalysts and found these mixed oxides exhibit better redox properties than pure CeO2. YAN Zhi-yong et al.[10] reported that the existence of ZrO2 in catalysts can raise its specific area and enhance the dispersion of CeO2 on catalysts which results in high activity of the catalysts. CeO2/TiO2-ZrO2 catalyst has strong tolerance to water vapor and sulfur dioxide.It is well known that ZrO2 exists mainly in three polymorphs with monoclinic (m-ZrO2), tetragonal (t-ZrO2) and (c-ZrO2) cubic structures[11]. ZrO2 polymorphs have different amphoteric character of its surface hydroxyl groups. The crystalline phase of ZrO2 has a great effect on the structure, activity and selectivity of catalysts. Therefore, it is valuable to investigate the effects of nanocrystalline zirconia polymorphs on catalytic properties of MnOx-CeO2/t-ZrO2 Catalysts which few researchers have concerned about. In this study, we try to investigate catalytic activity and microstructure of SCR catalysts with manganese oxide and cerium oxide supported on t-ZrO2.

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Yue, Lin, Qi Shan Wang, Jing Liang Yang, Xiao Luo, Jian Bo Guo, Jing Lian, and Kai Hong Wang. "Degradation of Landfill Leachate by Electro-Heterogeneous Catalytic Reactor." Advanced Materials Research 518-523 (May 2012): 3302–9. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.3302.

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Using granular activated carbon (GAC) as electric particle electrode and heterogeneous catalyst loaded metal oxide to replace insulated particle in bipolar packing bed cell (BPBC), the electro-heterogeneous catalytic oxidation system was constructed. Adopting impregnation method to prepare γ-Al2O3 supported catalysts containing Cu and Ce, it was evenly mixed with GAC to construct packing materials. Using stainless steel as anode, porous graphite as cathode and packing materials between them, landfill leachate was treated by an electro-catalytic oxidation process and COD removal efficiency was studied. The activity of catalysts was explored, and using scanning electron microscope (SEM) and X-ray diffraction (XRD), the microstructure and morphology were characterized. The operating parameters such as cell voltage, initial pH, airflow and inter-electrode distance were also investigated. The results showed that when the metal ion concentration in soaking solution was 2% for Cu, 9% for Ce, the activity of prepared catalyst was the highest. Under the conditions of an applied voltage of 15.0 V, pH of 7.0, airflow of 0.08 m3/h, and an inter-electrode distance of 3.0 cm, the removal efficiencies of COD reached 92.9%. Qualitative analysis of the interim products was carried out, adopting ultraviolet-visible spectrum, and the mechanism of electro-heterogeneous catalytic oxidation reaction was discussed. The whole degradation involves two main processes: electro-oxidation and electro-coagulation.

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Akdim, Ouardia, Umit Bilge Demirci, and Philippe Miele. "Metal Oxides (such as Al₂O₃ and TiO₂) as Catalyst Supports for Hydrogen Release by Hydrolysis of Sodium Borohydride NaBH₄." Advances in Science and Technology 65 (October 2010): 209–14. http://dx.doi.org/10.4028/www.scientific.net/ast.65.209.

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Hydrolysis of NaBH4 to release molecular hydrogen is today an intensely investigated reaction and most of the studies focus on the material used as catalyst. Among the various metals tested up to now, cobalt has soon showed to be the most attractive in terms of reactivity and cost. Nevertheless, in order to further decrease its cost by decreasing its amount as well as to increase its reactivity, cobalt has been dispersed over supports. The as-formed supported catalysts have showed to be more efficient. This is the topic of the present study. Herein it is showed that CoCl2 supported over an Al2O3 support with a specific surface area of 180 m2 g-1 is more reactive than CoCl2 supported over a high-surface-area activated carbon (780 m2 g-1), CoCl2 being in-situ reduced into the Co-based active phase. CoCl2-Al2O3 is besides as reactive as another CoCl2-Al2O3 catalyst, the latter support having a higher specific surface area (i.e. 250 m2 g-1). In fact, CoCl2-Al2O3 is more performing than neat CoCl2 whereas the latter has been often showed as being one of the best catalytic systems. To further gain in reactivity, a new, alternative strategy has been envisaged. The Al2O3 was mixed together with a controlled amount of another oxide, namely TiO2. The CoCl2- Al2O3-TiO2(20 wt%) was found to be more reactive than CoCl2-Al2O3. All of these reactivity data are reported and briefly discussed hereafter. Further studies are in progress to highlight the reasons of such improved reactivity.

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Badoga, Sandeep, Prachee Misra, Girish Kamath, Ying Zheng, and Ajay Dalai. "Hydrotreatment Followed by Oxidative Desulfurization and Denitrogenation to Attain Low Sulphur and Nitrogen Bitumen Derived Gas Oils." Catalysts 8, no. 12 (December 10, 2018): 645. http://dx.doi.org/10.3390/catal8120645.

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To lower the sulphur content below 500 ppm and to increase the quality of bitumen derived heavy oil, a combination of hydrotreating followed by oxidative desulfurization (ODS) and oxidative denitrogenation (ODN) is proposed in this work. NiMo/γ-Al2O3 catalyst was synthesized and used to hydrotreat heavy gas oil (HGO) and light gas oil (LGO) at typical operating conditions of 370–390 °C, 9 MPa, 1–1.5 h−1 space velocity and 600:1 H2 to oil ratio. γ-Alumina and alumina-titania supported Mo, P, Mn and W catalysts were synthesized and characterized using X-ray diffractions, N2 adsorption-desorption using Brunauer–Emmett–Teller (BET) method, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). All catalysts were tested for the oxidation of sulphur and nitrogen aromatic compounds present in LGO and HGO using tert-butyl hydroperoxide (TBHP) as oxidant. The oxidized sulphur and nitrogen compounds were extracted using adsorption on activated carbon and liquid-liquid extraction using methanol. The determination of oxidation states of each metal using XPS confirmed the structure of metal oxides in the catalyst. Thus, the catalytic activity determined in terms of sulphur and nitrogen removal is related to their physico-chemical properties. In agreement with literature, a simplistic mechanism for the oxidative desulfurization is also presented. Mo was found to be more active in comparison to W. Presence of Ti in the support has shown 8–12% increase in ODS and ODN. The MnPMo/γ-Al2O3-TiO2 catalyst showed the best activity for sulphur and nitrogen removal. The role of Mn and P as promoters to molybdenum was also discussed. Further three-stage ODS and ODN was performed to achieve less than 500 ppm in HGO and LGO. The combination of hydrotreatment, ODS and ODN has resulted in removal of 98.8 wt.% sulphur and 94.7 wt.% nitrogen from HGO and removal of 98.5 wt.% sulphur and 97.8 wt.% nitrogen from LGO.

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Aziz, Isalmi, Yessinta Kurnianti, Nanda Saridewi, Lisa Adhani, and Wahyu Permata. "Utilization of Coconut Shell as Cr2O3 Catalyst Support for Catalytic Cracking of Jatropha Oil into Biofuel." Jurnal Kimia Sains dan Aplikasi 23, no. 2 (February 17, 2020): 39–45. http://dx.doi.org/10.14710/jksa.23.2.39-45.

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Coconut shell waste is a waste that has a high carbon content. Carbon in coconut shell waste can be converted into activated carbon having a large surface area. This potential property is suitable to apply the coconut shell as catalyst support. To increase the catalytic activity, metal oxides such as Cr2O3 are impregnated. The purpose of this study is to synthesize Cr2O3/carbon catalyst and test its catalytic activity on catalytic cracking of Jatropha oil. The first stage was the synthesis of activated carbon and the determination of its proximate and ultimate. The second step was impregnation to produce Cr2O3/carbon catalyst. Furthermore, X-Ray Diffraction to determine crystallinity, Surface Area Analyzer to identify its surface area and Fourier Transform Infrared to analyze functional groups. Then the catalytic activity was tested on the catalytic cracking of Jatropha oil. In addition, the chemical compound composition and biofuel selectivity of the catalytic cracking product was determined using Gas Chromatography-Mass Spectrometer. Proximate analysis results showed that activated carbon contains 9%, 1%, 23%, and 67% of water, ash, evaporated substances, and bound carbon, respectively. The results of the ultimate analysis resulted in carbon (C), hydrogen (H), and nitrogen (N) contents of 65.422%, 3.384%, and 0.465%, correspondingly. The catalyst crystallinity test showed the presence of Cr2O3 peaks at 2θ: 24.43°; 33.47° and 36.25° according to JCPDS No. 84-1616. In the absorption area of 400-1000 cm-1 and the range of 2000 cm-1 showed the presence of Cr-O stretching due to Cr2O3 adsorbed into the activated carbon structure. The surface area of activated carbon and Cr2O3/carbon catalysts with a concentration of 1.3, and 5% was 8.930 m2/g; 47.205 m2/g; 50.562 m2/g; and 38.931 m2/g, respectively. The catalytic activity test presented that the best performance was showed by Cr2O3/carbon catalyst with a concentration of 5% indicated by conversion of Jatropha oil into biofuel of 67.777% with gasoline selectivity, kerosene, and diesel of 36.97%, 14.87%, and 15.94%, correspondingly.

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IWASHIMIZU, Emi, Noriaki TSUTSUMI, Hiroshi MORIYAMA, Kazuhisa MURATA, Takashi HAYAKAWA, Kunio SUZUKI, and Satoshi HAMAKAWA. "NO Reduction with Carbon over Metal Oxides Catalysts Supported on Activated Carbon." Journal of The Japan Petroleum Institute 44, no. 2 (2001): 125–30. http://dx.doi.org/10.1627/jpi1958.44.125.

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Yakub, Ibrahim. "Passive Nitrogen Oxides Removal from a Diesel-engine Exhaust Gas using a Biomass-Carbon Catalyst." Journal of Applied Science & Process Engineering 7, no. 1 (April 30, 2020): 479–88. http://dx.doi.org/10.33736/jaspe.2213.2020.

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Nitrogen oxides (NOx) removal from a diesel-engine exhaust gas is limited to the utilization of ammonia/urea as a reducing agent (SCR) which arose environmental concerns over the use of this chemical. Therefore, this study explored the potential of a sustainable NOx removal system by replacing ammonia with intrinsic reductants present in the exhaust gas such as hydrocarbons and carbon monoxide, and by application of cost-effective carbon-supported transitional metals catalyst. Copper-cerium catalyst supported over palm kernel shell activated carbon (Cu-Ce/PKS) was synthesized via deposition-precipitation method. The characterization shows that the catalyst has a considerably high surface area (though lower than the support). The high NOx removal by Cu-Ce/PKS in a passive catalytic reaction is attributed to the surface area provided by the carbon support, the low copper reducibility giving the low optimum operating temperature, and the synergistic effect between Cu and Ce resulting in the wide temperature window at low-temperature range. It is concluded that Cu-Ce supported over palm kernel shell activated carbon can be further developed to reduce NOx in a passive catalytic removal for a sustainable and cost-effective SCR system.

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Liu, Bing, Ai Min Li, Ming Fang Xia, and Zhao Lian Zhu. "Preparation of Manganese Oxide Supported on Activated Carbon and its Application in Catalytic Ozonation of 4-Chlorophenol." Advanced Materials Research 538-541 (June 2012): 2285–88. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.2285.

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Catalyst with manganese oxide highly dispersed on granular activated carbon (MnOx/GAC) was fabricated by impregnating GAC in MnCl2 solution and characterized by several techniques. The performance of manganese catalyst was investigated in catalytic ozonation of 4-chlorophenol in water. Manganese catalyst exhibits better efficiency than the original granular activated carbon, due to the synergic effect between activated carbon and manganese oxide. MnOx/GAC, produced by a simple methodin situ, is promising in catalytic ozonation of refractory organic pollutants in waste water.

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Nasrollahpour, A., and S. E. Moradi. "Photochemical degradation of methylene blue by metal oxide-supported activated carbon photocatalyst." Desalination and Water Treatment 57, no. 19 (May 26, 2015): 8854–62. http://dx.doi.org/10.1080/19443994.2015.1035675.

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Liu, Zhen-Shu, Yu-Hui Peng, and Wen-Kai Li. "Effects of activated carbon fibre-supported metal oxide characteristics on toluene removal." Environmental Technology 35, no. 12 (January 10, 2014): 1499–507. http://dx.doi.org/10.1080/09593330.2013.871351.

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25

Saad, Marwa, Agnieszka Szymaszek, Anna Białas, Bogdan Samojeden, and Monika Motak. "The Enhanced Performance of N-Modified Activated Carbon Promoted with Ce in Selective Catalytic Reduction of NOx with NH3." Catalysts 10, no. 12 (December 5, 2020): 1423. http://dx.doi.org/10.3390/catal10121423.

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The goal of the study was to modify activated carbon (AC) with nitrogen groups and ceria and to test the obtained materials in low temperature selective catalytic reduction of nitrogen oxides. For that purpose, the starting AC was oxidized with HNO3 of various concentrations, modified with urea and doped with 0.5 wt.% of Ce. It was observed that the increased concentration of acid influenced the catalytic activity, since textural and surface chemistry of activated carbon was changed. The most active sample was that modified with 14 M HNO3 and it reached 96% of NO conversion at 300 °C. Additionally, the addition of Ce improved the catalytic performance of modified AC, and NO was reduced according to oxidation–reduction mechanism, characteristic for supported metal oxides. Nevertheless, the samples promoted with Ce emitted significantly higher amount of CO2 comparing to the non-promoted ones.

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Li, Kunlin, Chi Wang, Ping Ning, Kai Li, Xin Sun, Xin Song, and Yi Mei. "Surface characterization of metal oxides-supported activated carbon fiber catalysts for simultaneous catalytic hydrolysis of carbonyl sulfide and carbon disulfide." Journal of Environmental Sciences 96 (October 2020): 44–54. http://dx.doi.org/10.1016/j.jes.2020.03.019.

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Wan, Zuraida, and B. H. Hameed. "Transesterification of palm oil to methyl ester on activated carbon supported calcium oxide catalyst." Bioresource Technology 102, no. 3 (February 2011): 2659–64. http://dx.doi.org/10.1016/j.biortech.2010.10.119.

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Jomhataikool, Buntita, Wachiraporn Gunpum, Wasawat Kraithong, Nawin Viriya-Empikul, and Apiluck Eiad-Ua. "Fantastic Carbon Material for Nickel/Carbon Support Catalyst Reducing via Calcination Enhanced with Hydrothermal Carbonization." Materials Science Forum 872 (September 2016): 201–5. http://dx.doi.org/10.4028/www.scientific.net/msf.872.201.

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In generally, the metal catalyst which synthesis by conventional techniques is usually in metal oxide form or easily oxidize in the air thus the metal catalyst must reduce to metallic form before using. It was complex process and dangerous. In the research, Carbon material from cattail flower (CF) were used as supporter of Nickel/Carbon supported metal catalyst (Ni/C). This research were studied effect of used carbon material from CF as supporter of Ni/C and varying nickel loading. The Ni/C catalyst were prepared by hydrothermal, impregnation and calcination process. Firstly, Dried CF has been pretreat via hydrothermal process with optimized condition at 180°C for 8h. Then, the nickel solution was added to support via impregnation method by varying Ni loading from 20 to 60 wt% of supported. Finally, the sample has been pelleted into 0.5mm-Ni/C pellet and calcined at 900°C for 2h under nitrogen atmosphere. Ni/C were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray (EDX), surface area and pore size distribution was determined by N2 adsorption. The result indicate that nickel particle on Ni/C were in the free metal from without reduction and well dispersed on supported surface. Particle size and surface area of Ni/C were decreases at the increase metal loading. Nickel/Carbon supported metal catalyst were ready to use and could be controlled particle size, surface area and crystallinity by metal loading.

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Kohli, Kirtika, Ravindra Prajapati, Samir K. Maity, and Brajendra Kumar Sharma. "Effect of Silica, Activated Carbon, and Alumina Supports on NiMo Catalysts for Residue Upgrading." Energies 13, no. 18 (September 22, 2020): 4967. http://dx.doi.org/10.3390/en13184967.

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The effect of different supports such as silica (SBA-15), activated carbon (AC), and mesoporous alumina (Al2O3) on catalytic activities of hydrotreating nickel molybdenum (NiMo) catalysts was demonstrated for upgrading vacuum residue. Nitrogen adsorption-desorption analysis showed that SBA-15 and the AC-supported NiMo catalyst possessed a very high surface area compared to the alumina-supported catalyst. However, NiMo/Al2O3 catalyst possesses a higher pore diameter and pore volume with an appropriate surface area. X-ray diffraction (XRD) analysis showed that active metals were dispersed in the catalytic supports. Transmission electron microscopy (TEM) analysis revealed the presence of type II active MoS2 sites in the NiMo/Al2O3 catalyst, which showed weak metal-support interactions having a high intrinsic activity. Catalyst activities such as hydrodesulfurization (HDS), hydrodemetallization (HDM) and asphaltene conversion (HDAs), and hydrocracking conversions of a vacuum residue were evaluated. The highest hydrotreating and hydrocracking conversions were observed with the NiMo catalyst supported on mesoporous alumina. The results also supported that the catalyst that has a large pore diameter, high pore volume, and better active metals dispersion is highly desirable for the upgrading of a vacuum residue.

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Ob-eye, Jeerati, Piyasan Praserthdam, and Bunjerd Jongsomjit. "Dehydrogenation of Ethanol to Acetaldehyde over Different Metals Supported on Carbon Catalysts." Catalysts 9, no. 1 (January 9, 2019): 66. http://dx.doi.org/10.3390/catal9010066.

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Recently, the interest in ethanol production from renewable natural sources in Thailand has been receiving much attention as an alternative form of energy. The low-cost accessibility of ethanol has been seen as an interesting topic, leading to the extensive study of the formation of distinct chemicals, such as ethylene, diethyl ether, acetaldehyde, and ethyl acetate, starting from ethanol as a raw material. In this paper, ethanol dehydrogenation to acetaldehyde in a one-step reaction was investigated by using commercial activated carbon with four different metal-doped catalysts. The reaction was conducted in a packed-bed micro-tubular reactor under a temperature range of 250–400 °C. The best results were found by using the copper doped on an activated carbon catalyst. Under this specified condition, ethanol conversion of 65.3% with acetaldehyde selectivity of 96.3% at 350 °C was achieved. This was probably due to the optimal acidity of copper doped on the activated carbon catalyst, as proven by the temperature-programmed desorption of ammonia (NH3-TPD). In addition, the other three catalyst samples (activated carbon, ceria, and cobalt doped on activated carbon) also favored high selectivity to acetaldehyde (>90%). In contrast, the nickel-doped catalyst was found to be suitable for ethylene production at an operating temperature of 350 °C.

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Lin, Sheng H., and Cheng L. Lai. "Catalytic oxidation of dye wastewater by metal oxide catalyst and granular activated carbon." Environment International 25, no. 4 (May 1999): 497–504. http://dx.doi.org/10.1016/s0160-4120(99)00015-x.

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32

Wan, Zuraida, Bassim H. Hameed, N. Mohammad Nor, and Nur Alwani Ali Bashah. "Optimization of Methyl Ester Production from Waste Palm Oil Using Activated Carbon Supported Calcium Oxide Catalyst." Solid State Phenomena 280 (August 2018): 346–52. http://dx.doi.org/10.4028/www.scientific.net/ssp.280.346.

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In this study, methyl ester (ME) was produced by transesterification of waste cooking palm oil (WPO) using activated carbon supported calcium oxide as a solid base catalyst (CaO/AC). Process optimization using response surface methodology (RSM) was applied to study the effect of reaction time, molar ratio of methanol to oil, reaction temperature and catalyst amount to produce highest ME content. The optimum reaction condition was at 5.5 wt% catalyst amount, 170 °C temperature, 15:1 methanol to oil molar ratio and 2 h 22 min reaction time. The predicted and experimental ME content were found to be 80.02% and 77.32%, respectively.

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Liu, J., S. M. Colburn, R. L. Ornberg, and J. R. Ebner. "Studies of surface and structural heterogeneity of carbon supports and carbon-supported catalysts." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 418–19. http://dx.doi.org/10.1017/s0424820100138464.

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Activated carbons are generally used as support materials for precious metal catalysts. Properties of carbon that are important to catalyst preparation and application include composition, surface area, microstructure and pore shape and size distribution. Macropores (> 50 nm), mesopores (2-50 nm) and micropores (<2 nm) generally coexist in activated carbons. The accessibility of metal particles dispersed in microporous systems is of predominant importance, especially for large molecules that exhibit slow diffusion transport in narrow pores. It is desirable to have metal particles highly dispersed in readily accessible locations. As part of an on-going program of the characterization of carbonsupported catalysts we report some preliminary observations of the microstructure of carbon supports by a variety of electron microscopy techniquesCommercial carbon supports and carbon-supported Pt catalysts were used in this study. High resolution secondary electron (SE) microscopy, low voltage backscattered electron (LVBE) microscopy and high-angle annular dark-field (HAADF) microscopy techniques were employed to extract surface and structural information.

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34

Park, Chanyeong, Soosan Kim, Yeonghwan Kwon, Chaehyeon Jeong, Yujin Cho, Chang-Gu Lee, Seungho Jung, Kwon-Young Choi, and Jechan Lee. "Pyrolysis of Polyethylene Terephthalate over Carbon-Supported Pd Catalyst." Catalysts 10, no. 5 (May 1, 2020): 496. http://dx.doi.org/10.3390/catal10050496.

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Pyrolysis of polyethylene terephthalate (PET) produces polycyclic hydrocarbons and biphenyl derivatives that are harmful to human health and the environment. Therefore, a palladium metal catalyst (5 wt.% Pd loaded on activated carbon) was used to prevent the formation of harmful materials. When a Pd catalyst/PET ratio of 0.01 was applied in pyrolysis of PET, it did not show a meaningful difference in the generation of polycyclic hydrocarbons and biphenyl derivatives. However, when a Pd catalyst/PET ratio of 0.05 was used during pyrolysis, it prevented their formation and generation at experimental temperature ranges (400–700 °C). For example, the concentration of 2-naphthalenecarboxylic acid produced, which is a typical polycyclic hydrocarbon material, was reduced by 44%. In addition, the concentration of biphenyl-4-carboxylic acid, which is contained in biphenyl derivatives, was reduced by 79% compared to non-catalytic pyrolysis at 800 °C. This was because the ring-opening reaction and free radical mechanism caused by the Pd catalyst and thermal cracking were dominant during the pyrolysis of PET. Apart from these materials, amine compounds were generated as products of the pyrolysis of PET. Amine concentration showed a similar trend with polycyclic hydrocarbons and benzene derivatives. Based on these results, the total concentration of polycyclic hydrocarbons and biphenyl derivatives was compared; the results confirmed that the concentrations of all substances were reduced. This research suggests that a metal-supported catalyst will help create a more environmentally friendly and reliable method of industrial plastic waste disposal.

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35

Amelia, Shinta, Wahyudi Budi Sediawan, Zahrul Mufrodi, and Teguh Ariyanto. "MODIFICATION OF IRON OXIDE CATALYSTS SUPPORTED ON THE BIOMASS BASED ACTIVATED CARBON FOR DEGRADATION OF DYE WASTEWATER." Jurnal Bahan Alam Terbarukan 7, no. 2 (January 9, 2019): 164–68. http://dx.doi.org/10.15294/jbat.v7i2.17174.

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Methylene blue is one of the dyes in textile industries which has a negative impact on the environment. This compound is very stable, so it is difficult to degrade naturally. Methylene blue can be harmful to the environment if it is in a very large concentration, because it can increase the value of Chemical Oxygen Demand (COD) which can damage the balance of environment ecosystem. Adsorption method by using activated carbon as the adsorbent is one of the most efficient and effective techniques in dye removal due to its large adsorption capacity. However, the adsorption method using activated carbon only removes the pollutant compounds to other media or phases. Other method that can be used includes Advanced Oxidation Processes (AOPs). This method has the advantage of being able to degrade harmful compounds in the waste through oxidation (oxidative degradation) processes. One method of AOPs is the process by using Fenton reagents. This study was aimed to prepare and characterize iron oxide/porous activated carbon catalyst. The type of porous activated carbon used was carbon from biomass derived carbon with microporous character. This biomass carbon is obtained from renewable natural products, namely coconut shell.The kinetics and adsorption models in the material will be derived and evaluated from the research data. Based on the research, it can be concluded that catalytic degradation is very effective for degradation of dye wastewater. Methylene blue degradation increases with the use of Fe2O3/activated carbon catalyst and the addition of hydrogen peroxide as the Fenton reagent. In addition, the pore structure difference in the catalyst also had a significant effect on the methylene blue degradation reaction resulting in increased capacity of methylene blue degradation reactions.

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Tapia, Juan, Nancy Y. Acelas, Diana López, and Andrés Moreno. "NiMo-sulfide supported on activated carbon to produce renewable diesel." Universitas Scientiarum 22, no. 1 (March 30, 2017): 71. http://dx.doi.org/10.11144/javeriana.sc22-1.nsoa.

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Due to their weak polarity and large surface area, activated carbon supports have the potential to enhance the dispersion of metal-sulfides. It is expected that the absence of a strong metal-support interaction can result in the formation of a very active and stable Ni-Mo-S phase. In this study, catalysts with different amounts of nickel and molybdenum supported on a commercial activated carbon were prepared by a co-impregnation method and characterized by BET, XRF, and SEM techniques. The catalytic activity for hydroprocessing of Jatropha oil was evaluated in a batch reactor, and the composition of the liquid and gaseous products were determined. Results showed that gaseous products are mainly composed of high amounts of propane and small amounts of other light hydrocarbons (C1 to C5). Liquid hydrocarbon products consisted of a mixture containing mainly n-paraffins of C15-C18 and some oxygenated compounds. The catalysts with a mass fraction<br />of 3 % Ni, 15 % Mo (Ni3Mo15/AC) presented the highest selectivity toward C17-C18 hydrocarbons, with a product distribution similar to a commercial<br />alumina-supported Ni-Mo-S catalyst.

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Dai, Hui, Mingyuan Zhu, Haiyang Zhang, Feng Yu, Chao Wang, and Bin Dai. "Activated Carbon Supported Mo-Ti-N Binary Transition Metal Nitride as Catalyst for Acetylene Hydrochlorination." Catalysts 7, no. 7 (June 30, 2017): 200. http://dx.doi.org/10.3390/catal7070200.

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Karthikeyan, S., R. Bavas Ahamed, M. Velan, and G. Sekaran. "Synthesis and characterization of Co-NPAC and in situ hydroxyl radical generation for the oxidation of dye laden wastewater from the leather industry." RSC Adv. 4, no. 108 (2014): 63354–66. http://dx.doi.org/10.1039/c4ra10536b.

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39

Abdulkareem-Alsultan, Ghassan, N. Asikin-Mijan, and Yun Hin Taufiq-Yap. "Effective Catalytic Deoxygenation of Waste Cooking Oil over Nanorods Activated Carbon Supported CaO." Key Engineering Materials 707 (September 2016): 175–81. http://dx.doi.org/10.4028/www.scientific.net/kem.707.175.

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Under nitrogen atmosphere, waste cooking oil (WCO) was deoxygenated in semi-batch experiments by using the nanorods of phosphate-activated carbon, which is derived from walnut shell and promoted by CaO as catalyst at 350 °C. The deoxygenation reaction showed high activity (> 48% hydrocarbon yield) and high selectivity towards decarboxylation/decarbonylation (deCOx) reactions via exclusive formation of green diesel C15 fraction (> 60%). The high activity and high selectivity were attributed to the good physicochemical characteristics of the catalyst, including improved metal dispersion, high surface area and high basic properties. Overall, this study demonstrates CaO/AC catalytic deoxygenation as a promising approach to produce liquid green diesel C15 from WCO under hydrogen-free atmosphere.

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Kong, Ling Niao, Ya Ru Huang, and Yin Jun Fang. "Phenol In Situ Hydrogenation with Carbon Nanotube-Supported Pd Catalyst." Advanced Materials Research 934 (May 2014): 60–64. http://dx.doi.org/10.4028/www.scientific.net/amr.934.60.

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Carbon nanotube (CNT) and activated carbon (AC)-supported Pd catalysts have been prepared by impregnation and reduction-precipitation method using chloropalladate acid as metal precursor. The catalytic performance for phenol in-situ hydrogenation was evaluated under 493 K, 3.5MPa. The results show that Pd/CNTs catalyst has higher selective for phenol in-situ hydrogenation to cyclohexanone. The catalysts have been characterised by CO-TPD and TEM. The mesoporosity structure and inner hollow cavities of Pd/CNTs catalyst are responsible for the distinguished properties.

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41

Hidalgo Herrador, José Miguel, Zdeněk Tišler, Jaroslav Kocík, Jakub Fratcząk, Ivana Hradecká, Romana Velvarská, and Héctor de Paz Carmona. "Mesityl Oxide Reduction by Using Acid-Modified Phonolite Supported NiW, NiMo, and CoMo Catalysts." Catalysts 11, no. 9 (September 13, 2021): 1101. http://dx.doi.org/10.3390/catal11091101.

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Mesityl oxide is standardly used to produce methyl iso butyl ketone but it can be also used to produce other useful compounds. Three catalysts were used for the reaction of the mesityl oxide reduction. They were NiW, NiMo, and CoMo supported on phonolite modified by HCl (metals/Ph-HCl). The fresh catalysts were characterized by XRD, XRF, BET surface, Hg porosimetry, SEM, H2-TPR, NH3-TPD, CO2-TPD. The materials were directly used, previously reduced in H2 or sulfided for the mesityl oxide reduction under H2 atmosphere. The reaction was performed in an autoclave at T = 375 °C, p = 50 bar (H2), and TOS = 1.5 h. The products were analyzed by GC/MS, GC/FID-TCD, ATR. The main products were methyl isobutyl ketone, 2-methyl pentane, and 2-methyl-2-pentene. Sulfided metal catalysts were the most active in the methyl isobutyl ketone, where the NiWSx/Ph-HCl catalyst showed the highest activity. For the non-previously-activated and hydrogen activated catalysts the most active catalyst was the NiMo/Ph-HCl for the production of methyl isobutyl ketone. The catalyst CoMo/Ph-HCl activated in hydrogen was the most active for the production of 2-methyl pentane compared to the other two hydrogen-activated materials.

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Matus, E. V., L. M. Khitsova, O. S. Efimova, S. A. Yashnik, N. V. Shikina, and Z. R. Ismagilov. "Preparation of Carbon Nanotubes with Supported Metal Oxide Nanoparticles: Effect of Metal Precursor on Thermal Decomposition Behavior of the Materials." Eurasian Chemico-Technological Journal 21, no. 4 (December 18, 2019): 303. http://dx.doi.org/10.18321/ectj887.

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To develop new catalysts based on carbon nanomaterials with supported metal oxide nanoparticles for oxidative transformations of sulfur compounds, a series of metal oxide nanoparticle-decorated carbon nanotubes (MOx/CNTs) were prepared by incipient wetness impregnation at a variation of the active metal type (M = Ce, Mo, Cu). The thermal decomposition of bulk and CNT supported metal precursors used in the preparation of MOx/CNTs was analyzed under inert atmosphere employing several thermoanalytical techniques (thermogravimetry, differential thermogravimetry and differential scanning calorimetry) coupled with mass spectrometry. The thermolysis parameters of the bulk and supported metal precursors were compared and the effect of CNT support on the decomposition pattern of compounds was elucidated. It was established that the decomposition of metal precursors supported on CNTs was started and completed at temperatures of 15‒25 and 25‒70 °C lower, respectively, compared with the bulk active metal precursor. The enhancement of CNT support stability against thermal degradation is observed in the following row of metal cations: Ce < Cu < Мо < pristine and metal anions of precursor: nitrate < chloride < sulfate. The optimal mode of thermal treatment of catalyst and appropriate active metal precursors were selected for advanced synthesis of nanosized MOx/CNT catalyst.

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Han, Yue, Guangxing Wang, Wenfeng Qiu, Ying Guo, Yanan Sun, Youlan Zhang, Heng Zhou, and Tong Zhao. "Activated‐Carbon‐Supported Calcium Oxide: A Selective and Efficient Catalyst for Nitrile‐Containing Diaryl Ether Synthesis." Asian Journal of Organic Chemistry 7, no. 12 (October 30, 2018): 2511–17. http://dx.doi.org/10.1002/ajoc.201800588.

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Zhu, Zhenping, Zhenyu Liu, Hongxian Niu, Shoujun Liu, Tiandou Hu, Tao Liu, and Yaning Xie. "Mechanism of SO2 Promotion for NO Reduction with NH3 over Activated Carbon-Supported Vanadium Oxide Catalyst." Journal of Catalysis 197, no. 1 (January 2001): 6–16. http://dx.doi.org/10.1006/jcat.2000.3052.

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45

Arie, Arenst Andreas, Hans Kristianto, Ratna Frida Susanti, Hary Devianto, Martin Halim, and Joong Kee Lee. "Characterizations of Carbon Nanospheres Synthesized Using Activated Carbons and Palm Oil." Advanced Materials Research 1112 (July 2015): 53–56. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.53.

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Carbon Nanospheres (CNSs) have been synthesized by thermal pyrolysis method. A mixture of Fe-catalyst supported activated carbons and palm oil was used in the furnace to produce CNSs. Prior to the synthesis of CNSs, Fe-catalyst was deposited onto the surface of activated carbons by wet incipient impregnation method. The ratio of carbon support and palm oil was varied (1:1, 1: 2 and 1:3) to obtain CNSs. The characteristics of produced CNSs were then evaluated with BET surface area analysis, pore size distribution analysis, scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that some impurities were still found in the CNSs in the forms of iron oxide and amorphous carbons.

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Alias, Aznira, Noraini Hamzah, and Mohd Ambar Yarmo. "Hydrogenolysis of Glycerol to Propanediols over Nano-Ru/C Catalyst with Ionic Liquid Addition." Advanced Materials Research 173 (December 2010): 49–54. http://dx.doi.org/10.4028/www.scientific.net/amr.173.49.

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Supported ruthenium catalyst on nano-activated carbon (2%Ru/C) and titania (2%Ru/TiO2) were prepared by wet impregnation technique with and without ionic liquid addition (choline chloride with different Lewis acid). Mole ratio of choline chloride and Lewis acid were fixed at 1:3. Catalysts evaluation was performed by glycerol hydrogenolysis reaction at 100°C with initial hydrogen pressure 20 bars for 7 hours reaction. The results showed that supported ruthenium on activated carbon acetylene black with addition of choline chloride/zinc (II) chloride catalyst indicated 30.7% of glycerol converted to 20.6% propylene glycol and 11.4% ethylene glycol. Catalysts profile of XRD showed graphitic phase which could reduce catalyst poisoning effect. XPS analysis showed that Ru/CC-ZnCl2/C catalyst spesies was in Ru4+ state before reaction. In the meantime, mapping analysis using FE-SEM showed well dispersion of ruthenium metal on nano-activated carbon acetylene black with addition of choline chloride/zinc (II) chloride gave the highest selectivity to propanediol. Furthermore, smaller size of nano activated carbon (30-60 nm) than titania (90-120nm) analyzed by TEM may the main course in increasing the conversion of glycerol.

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Fusini, Graziano, Fabio Rizzo, Gaetano Angelici, Emanuela Pitzalis, Claudio Evangelisti, and Adriano Carpita. "Polyvinylpyridine-Supported Palladium Nanoparticles: An Efficient Catalyst for Suzuki–Miyaura Coupling Reactions." Catalysts 10, no. 3 (March 15, 2020): 330. http://dx.doi.org/10.3390/catal10030330.

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Palladium nanoparticles (Pd NPs) synthesized by the metal vapor synthesis technique were supported on poly(4-vinylpyridine) 2% cross-linked with divinylbenzene (Pd/PVPy). Transmission electron microscopy revealed the presence of small metal nanoparticles (dm = 2.9 nm) highly dispersed on the PVPy. The Pd/PVPy system showed high catalytic efficiency in Suzuki-Miyaura carbon–carbon coupling reactions of both non-activated and deactivated aromatic iodides and bromides with aryl boronic acids, carried out under an air atmosphere. The high turnover of the catalyst and the ability of the PVPy resin to retain active Pd species are highlighted. By comparing the catalytic performances of Pd/PVPy with those observed by using commercially available Pd-based supported catalysts, the reported system showed higher selectivity and lower Pd leaching.

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Anthonysamy, Shahreen Binti Izwan, Syahidah Binti Afandi, Mehrnoush Khavarian, and Abdul Rahman Bin Mohamed. "A review of carbon-based and non-carbon-based catalyst supports for the selective catalytic reduction of nitric oxide." Beilstein Journal of Nanotechnology 9 (February 27, 2018): 740–61. http://dx.doi.org/10.3762/bjnano.9.68.

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Various types of carbon-based and non-carbon-based catalyst supports for nitric oxide (NO) removal through selective catalytic reduction (SCR) with ammonia are examined in this review. A number of carbon-based materials, such as carbon nanotubes (CNTs), activated carbon (AC), and graphene (GR) and non-carbon-based materials, such as Zeolite Socony Mobil–5 (ZSM-5), TiO2, and Al2O3 supported materials, were identified as the most up-to-date and recently used catalysts for the removal of NO gas. The main focus of this review is the study of catalyst preparation methods, as this is highly correlated to the behaviour of NO removal. The general mechanisms involved in the system, the Langmuir–Hinshelwood or Eley–Riedeal mechanism, are also discussed. Characterisation analysis affecting the surface and chemical structure of the catalyst is also detailed in this work. Finally, a few major conclusions are drawn and future directions for work on the advancement of the SCR-NH3 catalyst are suggested.

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Ochoa, Elba, Daniel Torres, José Luis Pinilla, and Isabel Suelves. "Nanostructured Carbon Material Effect on the Synthesis of Carbon-Supported Molybdenum Carbide Catalysts for Guaiacol Hydrodeoxygenation." Energies 13, no. 5 (March 5, 2020): 1189. http://dx.doi.org/10.3390/en13051189.

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The impact of using different nanostructured carbon materials (carbon nanofibers, carbon nanotubes, graphene oxide and activated carbon) as a support for Mo2C-based catalysts on the hydrodeoxygenation (HDO) of guaiacol was studied. To optimise the catalyst preparation by carbothermal hydrogen reduction (CHR), a thermogravimetric study was conducted to select the optimum CHR temperature for each carbon material, considering both the crystal size of the resulting β-Mo2C particles and the extent of the support gasification. Subsequently, catalysts were prepared in a fixed bed reactor at the optimum temperature. Catalyst characterization evidenced the differences in the catalyst morphology as compared to those prepared in the thermogravimetric study. The HDO results demonstrated that the carbon nanofiber-based catalyst was the one with the best catalytic performance. This behaviour was attributed to the high thermal stability of this support, which prevented its gasification and promoted a good evolution of the crystal size of Mo species. This catalyst exhibited well-dispersed β-Mo2C nanoparticles of ca. 11 nm. On the contrary, the other supports suffered from severe gasification (60–70% wt. loss), which resulted in poorer HDO efficiency catalysts regardless of the β-Mo2C crystal size. This exhibited the importance of the carbon support stability in Mo2C-based catalysts prepared by CHR.

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Kurniawansyah, Firman, Ratna Dewi Pertiwi, Mahendra Perdana, Muhammad Al-Muttaqii, and Achmad Roesyadi. "Development of Bamboo - Derived Activated Carbon as Catalyst Support for Glucose Hydrogenation." Materials Science Forum 988 (April 2020): 108–13. http://dx.doi.org/10.4028/www.scientific.net/msf.988.108.

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Abstract:

Indonesia possesses high potential to develop an advanced biorefinery system, thanks to its high richness of natural resources. Bamboo for instance, with more than 200 species, in which 5% of its global distribution is found in Indonesian archipelago, is an invaluable resource to develop many useful materials. Here in this study, bamboo has been used to produce activated carbon for catalyst material. Bamboo raw material was obtained from a city park in Surabaya, and converted to activated carbon through carbonization at 773 K, followed by activation using acidic solution. The activated carbon (AC) was used as catalyst support, impregnated by nickel (Ni) as metal active. The catalyst was used in conversion of glucose to glucitols (sorbitol, mannitol) trough reduction with hydrogen. The Ni/AC was applied as catalyst for hydrogenation of glucose, conducted at 0.5 MPa and 363 – 403 K. With surface area of 125 m2/g of the carbon supported catalyst applied, glucose could be converted to polyols with overall yield of approximately 3 wt % from the total products.

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Journal articles on the topic 'Activated carbon supported metal oxide catalyst'

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