Journal articles: 'Butene'

1

Bachl, F., and H. D. Lüdemann. "Pressure and Temperature Dependence of Self-Diffusion in Liquid Linear Hydrocarbons." Zeitschrift für Naturforschung A 41, no. 7 (1986): 963–70. http://dx.doi.org/10.1515/zna-1986-0711.

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The pressure and temperature dependence o f the self-diffusion coefficients D of n-butane, n-pentane, n-hexane, n-decane, trans-2-butene, cis-2-butene and 2-butyne were determined in the liquid state by NM R-techniques at pressure up to 200 MPa and temperatures up to 450 K. The results are taken as tests for the various dynamical models and compared to results obtained by M D calculations. The activation parameters for translational transport and the parameters for the RHS-m odel are derived and discussed.

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BELELLI, PATRICIA G., and NORBERTO J. CASTELLANI. "A THEORETICAL STUDY OF UNSATURATED OLEFIN HYDROGENATION AND ISOMERIZATION ON Pd(111)." Surface Review and Letters 15, no. 03 (2008): 249–59. http://dx.doi.org/10.1142/s0218625x08011329.

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The addition of hydrogen to the carbon–carbon double bond of 2-butenes adsorbed on Pd (111) was studied within the density functional theory (DFT) and using a periodic slab model. For that purpose, the Horiuti–Polanyi mechanisms for both complete hydrogenation and isomerization were considered. The hydrogenation of cis and trans-2-butene to produce butane proceeds via the formation of eclipsed and staggered-2-butyl intermediates, respectively. In both cases, a relatively high energy barrier to produce the half-hydrogenated intermediate makes the first hydrogen addition the slowest step of the reaction. The competitive production of trans-2-butene from cis-2-butene requires the conversion from the eclipsed-2-butyl to the staggered-2-butyl isomer. As the corresponding energy barrier is relatively small and because the first of these isomers is less stable than the second, an easy conversion is predicted.

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Huseynova, Galina, Gulbeniz Мuхtаrоvа, Nushaba Aliyeva, Gular Gаsimоvа, and Sanubar Rаshidоvа. "Zeolite-Containing Catalysts in Alkylation Processes." Catalysis Research 2, no. 3 (2022): 1. http://dx.doi.org/10.21926/cr.2203019.

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This article provides an overview of zeolite-containing catalysts used in the alkylation of benzene and toluene with olefins, isobutane with butenes and butane-butene fractions, gasoline and oil fractions with olefins, propane-propylene, and butane-butylene fractions of catalytic cracking. Zeolites have various types of structures, including BEA, MFI, MWW, FAU, etc., which differ in pore size and the number and location of the channels. High-silica zeolites have a large pore volume, high acidity, good hydrothermal stability, and molecular sieve properties that provide high selectivity in alkylation processes.

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Huseynova, G. A., G. S. Mukhtarova, S. Y. Rashidova, and G. A. Gasimova. "Zeolite-containing catalysts in alkylation processes." Azerbaijan Oil Industry, no. 10 (October 15, 2022): 41–46. http://dx.doi.org/10.37474/0365-8554/2022-10-41-46.

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The paper reviews the zeolite-containing catalysts applied in alkylation processes of benzole and tolene with olefines, isobutene with butenes and butane-butene fractions, gasoline and oil fractions with olefins, propane-propylene and butane-butylene fractions of catalytic cracking as well. The zeolites are presented with the structures of BEA, MFI, MWW, FAU etc. types differing with pore size, with quantity and location of the channels. High-silica zeolites are characterized with high volume of pores, high acidity, hydrothermal stability, as well as with shape-selective properties providing high selectiveness in alkylation processes.

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Aghayeva, K. X., and V. L. Baghiyev. "INVESTIGATION OF THE ISOMERIZATION REACTION OF BUTENE-1 TO BUTENES-2 ON BINARY TUNGSTEN-CONTAINING CATALYSTS." Chemical Problems 20, no. 3 (2022): 256–63. http://dx.doi.org/10.32737/2221-8688-2022-3-256-263.

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The activity of tungsten-containing catalysts in the reaction of isomerization of butene-1 to butenes-2 was studied in the work. The results obtained showed that the ^ introduction of the second element into the composition of the tungsten oxide catalyst had a different effect on its activity in the butene-1 isomerization reaction. It was established that an increase in the amount of molybdenum in the composition of a binary tungsten-containing catalyst at low temperatures leads to a decrease in the degree of butene-1 isomerization while at high temperatures it leads to an increase in the rate of butene-1 isomerization. It found that the addition of titanium to the composition of the tungsten oxide catalyst leads to an increase in the butene-1 isomerization rate. When copper is added to the composition of the tungsten oxide catalyst, the total yield of butene-2 passes through a maximum, and on samples rich in copper, the isomerization of butene-1 practically does not occur. It revealed that the activity of binary tungsten oxide catalysts in the isomerization reaction of butene-1 to butenes-2 changes in the following order: Ti-W-O > Mo-W-O > Cu-WO.

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Fəridə Mədətova, Əzizə Zeynalova, Fəridə Mədətova, Əzizə Zeynalova, та Dilarə İsmayılova, Vaqif Bağıyev Dilarə İsmayılova, Vaqif Bağıyev. "BUTEN-1-in BUTEN-2-yə İZOMERLƏŞMƏSİ REAKSİYASINDA BİNAR KOBALT TƏRKİBLİ KATALİZATORLARIN AKTİVLİYİ". PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 34, № 11 (2023): 75–84. http://dx.doi.org/10.36962/pahtei34112023-75.

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Hydrogen is considered the main source of chemical energy that can be converted directly into electricity and with the help of fuel cells into zero emissions of harmful waste, such as volatile organic compounds, nitrogen oxides and carbon. The production of hydrogen in accordance with the generation of energy using a fuel cell is considered a promising alternative to stationary and portable power generation plants in the future. Various methods are used to produce hydrogen: water electrolysis, gasification, partial oxidation of heavy oil and steam corrugation of organic compounds. Currently, in industry, about 90% of hydrogen is produced by the reaction of high-temperature steam reforming of light fractions of natural gas or oil. An attractive alternative to hydrogen production is the reaction of ethanol steam reforming. The activity of binary iron-cobalt, zinc-cobalt and magnesium-cobalt oxide catalysts in the reaction of isomerization of butene-1 to butenes-2 was studied. Iron-cobalt, zinc-cobalt and magnesium-cobalt oxide catalysts were prepared by co-precipitation from aqueous solutions of iron, zinc, magnesium and cobalt nitrate salts. The resulting mixture was evaporated at 95-100°C, then the resulting precipitate was dried at 100-120°C and then decomposed at 250°C until the nitrogen oxides were completely separated. The resulting solid was calcined at 700°C for 10 hours. Thus, 27 catalysts were prepared satisfying the following conditions: mA/NB, where A is Mo, Ti, Cu; cis, m,n=1-9, m+n=10. The isomerization reaction of butene-1 to butene-2 was carried out at a rate of 1200 h-1 volume of feedstock in the temperature range of 150-400°C. The reactor was filled with 5 mL of 1-2 mm thick catalyst and fed with a reaction mixture consisting of butene-1 and nitrogen. The ratio of butene-1 to nitrogen is 1:9. It is shown that with increasing cobalt content in the Fe-Co-o catalyst composition, its activity in the isomerization reaction reaches a maximum on catalysts with equivalent ratio of initial elements. The ratio of trans- and cis-butenes-2 practically does not change and is equal to 1.2. It is found that both Lewis acid centers and Bransted acid centers are present on the surface of this catalyst in approximately equal amounts. It was found that with increasing zinc content in the catalyst composition, the degree of butene-1 isomerization decreases and the ratio of trans-butene-2 to cis-butene-2 increases from 0 to 2.1, indicating the presence of Lewis and Bronsted acid centers on the surface of Zn-Co-O catalysts. It is found that for the Mg-Co-O catalytic system the ratio of trans and cis butenes-2 yields varies in the range 0.8-1.5. It is shown that, in the whole temperature range studied, the atomic ratio of cobalt and magnesium has a strong influence on their activity in the reaction of Butene-1 isomerization into Butene-2. It is found that the number of Lewis and Bronsted acid centers is practically independent of the composition of the Mg-Co-O catalytic system. Based on the study of the reaction of butene-1 to butene-2 isomerization on binary cobalt-containing catalysts, it was found that the samples with equimolar ratios of primary elements in Fe-Co-O catalysts, as well as samples with one of the predominant elements in the catalytic systems Zn-Co-O and Mg-Co-O are active. Keywords: Isomerization, butene-1, butenes-2, binary catalysts Cobalt oxide.

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Yi, Fengjiao, Mengjiao Xing, Jing-Pei Cao, Shupeng Guo, and Yong Yang. "Comparison of Brønsted Acidic Silanol Nests and Lewis Acidic Metal Sites in Ti-Beta Zeolites for Conversion of Butenes." Catalysts 14, no. 11 (2024): 749. http://dx.doi.org/10.3390/catal14110749.

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The Lewis acidic framework Ti sites in Ti-Beta and Si-Beta catalysts were compared by FT-IR and NMR characterization methods before they were applied to the conversion of four butenes. The results showed that Si-Beta has fewer Lewis acid sites and abundant weak Brønsted acidic silanol nests, which play an important role in conversions between n-butene, cis-2-butene, and trans-2-butene. The conversions for these butenes over Si-Beta were always higher than those over a series of Ti-Beta catalysts with gradient-varied Lewis acidic framework Ti sites and silanols. This is because isobutene can only oligomerize, which requires stronger acidity, so its conversion over Si-Beta was lower than those over Ti-Beta zeolites. For a series of Ti-Beta catalysts with different abundances of Lewis acidic Ti sites, the more Lewis acid sites it had, the higher the conversions for the four butenes.

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8

Al-Auda, Zahraa, and Keith L. Hohn. "Production of Butane from Methyl Ethyl Ketone over Pt/Al2O3." Bulletin of Chemical Reaction Engineering & Catalysis 18, no. 1 (2023): 17–24. http://dx.doi.org/10.9767/bcrec.16693.

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Methyl ethyl ketone (MEK) was catalytically converted to butane directly in one step over platinum (Pt) supported on alumina (Al2O3). The reaction was performed in the gas phase in a fixed bed reactor. Conversion of MEK to butane was achieved by hydrogenation of MEK to 2-butanol, dehydration of 2-butanol to butene, and further hydrogenation of butene to butane. The results showed that butane can be produced with selectivity reaching 95% depending on the operating conditions. The highest selectivity for butane was obtained at 220 °C and a H2/MEK molar ratio of 15. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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9

Nofrizal, Nofrizal, Lisna Rosmayati, and Yayun Andriani. "A Rapid Gas Chromatography Method For Simultaneous Determination Of Lpg Compounds." Scientific Contributions Oil and Gas 36, no. 3 (2022): 145–51. http://dx.doi.org/10.29017/scog.36.3.772.

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A rapid gas chromatography method using a HP Plot/Al2O3 column for the determination of thirteen compounds of LPG (Liquefied Petroleum Gas) standard (ethane, propane, propylene, iso-butane, n-butane, trans-2-butene, 1-butene, isobutylene, neo-pentane, cis-2-butene, iso-pentane, n-pentane, 1,3 butadiene) was developed. The LPG components were separated in about 8 min by gradient elution program and helium was used as a carrier gas at a flow rate of 5 mL min-1, The relative standard deviation (RSD) for the LPG standard concentration were found to range between 0.27-1.91 % . The method had been applied to the determination of the 10 LPG samples. The composition of analyzed samples have comply with the Indonesian LPG specification for each parameter (C20.8 % mol, C3+C497 % mol and C5+.2.0 % mol).

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10

Preißler-Kurzhöfer, Hannes, Marcus Lange, Jens Möllmer, et al. "Hydrocarbon Sorption in Flexible MOFs—Part III: Modulation of Gas Separation Mechanisms." Nanomaterials 14, no. 3 (2024): 241. http://dx.doi.org/10.3390/nano14030241.

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Single gas sorption experiments with the C4-hydrocarbons n-butane, iso-butane, 1-butene and iso-butene on the flexible MOFs Cu-IHMe-pw and Cu-IHEt-pw were carried out with both thermodynamic equilibrium and overall sorption kinetics. Subsequent static binary gas mixture experiments of n-butane and iso-butane unveil a complex dependence of the overall selectivity on sorption enthalpy, rate of structural transition as well as steric effects. A thermodynamic separation favoring iso-butane as well as kinetic separation favoring n-butane are possible within Cu-IHMe-pw while complete size exclusion of iso-butane is achieved in Cu-IHEt-pw. This proof-of-concept study shows that the structural flexibility offers additional levers for the precise modulation of the separation mechanisms for complex mixtures with similar chemical and physical properties with real selectivities of >10.

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11

Hanaoka, Toshiaki, Masaru Aoyagi, and Yusuke Edashige. "Synthesis of n-Butene via Dimethyl Ether-to-Olefin Reaction over P-Loaded Ferrierite Zeolites." Catalysts 14, no. 12 (2024): 902. https://doi.org/10.3390/catal14120902.

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In the dimethyl ether (DME)-to-olefin (DTO) reaction over 20 types of P-loaded ferrierite zeolites with different P loading amounts, the synthesis of n-butenes such as 1-butene, trans-2-butene, and cis-2-butene was investigated to maximize the n-butene yield by optimizing the P loading amount. The zeolites were characterized using X-ray diffractometry (XRD), N2 adsorption-desorption isotherms, and NH3 temperature-programmed desorption (NH3-TPD). Micropore and external surface areas, total pore and micropore volumes, and weak and strong acids affected the DTO reaction’s characteristics. The P-loaded ferrierite zeolite with a P loading of 0.3 wt.% calcined at 500 °C exhibited an n-butene yield of 35.7 C-mol%, which exceeds the highest yield reported to date (31.2 C-mol%). Multiple regression analysis using the obtained data showed that the strong acid/weak acid ratio and total pore volume had a high correlation with the n-butene yield, with a contribution rate of 64.3%. Based on the multiple regression analysis results, the DTO reaction mechanism was discussed based on the proposed reaction model involving the dual-cycle mechanism.

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12

Andrei, Andrei Maxim, and Costin Sorin Bildea. "Optimization and Control of Propylene Production by Metathesis of 2-Butene." Processes 11, no. 5 (2023): 1325. http://dx.doi.org/10.3390/pr11051325.

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This article considers the design and control of the 2-butene metathesis process. The process transforms a low-value feedstock derived from a fluid catalytic cracking unit into more valuable products. The economical optimization is applied to the preheat–reaction and separation sections, with the objective of minimizing the total annual cost. The dynamic response and control of the plant are evaluated for feed flow perturbations. Although the process control system acts as a first line of defense against potential hazards, other independent safety layers are discussed with safety limits specific to the critical equipment of the 2-butene metathesis unit. The results prove that the metathesis reaction of 2-butene over a mesoporous tungsten catalyst is economically attractive. For a 5.7 t/h feed rate consisting of 2-butene (70% molar) and n-butane (30% molar), a reaction–separation plant (without recycle) requires 6570 × 103 $ investment and has a profitability of 2300 × 103 $/year.

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Shu, Miao, Chuang Shi, Jing Yu, Xiao Chen, Changhai Liang, and Rui Si. "Efficient selective hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol by silicon carbide supported platinum catalyst." Catalysis Science & Technology 10, no. 2 (2020): 327–31. http://dx.doi.org/10.1039/c9cy01877h.

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14

Bethardy, G. A., Xiaouang Wang, and David S. Perry. "The role of molecular flexibility in accelerating intramolecular vibrational relaxation." Canadian Journal of Chemistry 72, no. 3 (1994): 652–59. http://dx.doi.org/10.1139/v94-090.

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Evidence is presented to show that intramolecular vibrational relaxation (IVR) is faster in flexible molecules when the initially prepared vibration is close to the bond about which the large-amplitude motion occurs. In each of 1-pentyne, ethanol, and propargyl alcohol, IVR lifetimes are known for two different hydride stretches and in each molecule internal rotation connects gauche and trans conformers. In each case the vibration that is closer to the center of flexibility shows faster relaxation. This trend is supported by the available IVR lifetimes for other flexible molecules (hydrogen peroxide, 1-butene, n-butane, methyl formate, and propargyl amine) and for some "rigid" molecules (1-butyne, isobutane, propyne, trans-2-butene, and tert-butylacetylene). The lifetimes for the halogenated molecules, 2-fluoroethanol, 1,2-difluoroethane, trans-1-chloro-2-fluoroethane, and trifluoropropyne are all in the range expected for rigid molecules. An algorithm is presented for the consistent calculation of IVR lifetimes from discrete frequency-resolved spectra, which range from the sparse through intermediate coupling cases. Wherever possible, the reported lifetimes have been calculated (or recalculated) from the original line positions and intensities. The lifetimes may be compared directly to those deduced from homogeneously broadened spectral features with a Lorentzian contour.

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Taghi, T. Ch, I. J. Ahmadova, and V. L. Baghiyev. "DEPENDENCE OF THE ACTIVITY OF Ce-Zn-O CATALYSTS IN THE REACTION OF THE CONVERSION OF ETHANOL INTO ACETONE ON THE ACIDIC PROPERTIES OF THE SURFACE." Chemical Problems 21, no. 2 (2023): 146–52. http://dx.doi.org/10.32737/2221-8688-2023-2-146-152.

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The reaction of ethanol conversion to acetone on binary cerium-zinc oxide catalysts has been studied. It has been established that the reaction products of the conversion of ethyl alcohol on binary cerium-zinc oxide catalysts are ethylene, acetaldehyde, acetone, carbon dioxide and, at high temperatures, destructive decomposition products. The highest yield of acetone is observed on samples rich in zinc at temperatures of the order of 450-550°C, while catalysts rich in cerium are active in the reaction of dehydration of ethanol to ethylene. In this work, the acid properties of cerium-zinc oxide catalysts were evaluated by their activity in the isomerization of butene-1 to trans and cis butenes-2. It was found that cerium-rich catalysts are active in butene-1 isomerization reaction. The activities of cerium-zinc oxide catalysts in the reactions of the conversion of ethanol to acetone and the isomerization of butene-1 into trans and cis butenes-2 are compared. It was found that the reaction of the conversion of ethanol to acetone proceeds on the centers of the basic nature, and the formation of ethylene proceeds on the centers of the acidic nature.

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Manzanares I., Carlos, Victor M. Blunt, and Jingping Peng. "Spectroscopy of C-H stretching vibrations of gas-phase butenes: cis-2-butene, trans-2-butene, 2-methyl-2-butene, and 2,3-dimethyl-2-butene." Journal of Physical Chemistry 97, no. 16 (1993): 3994–4003. http://dx.doi.org/10.1021/j100118a013.

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17

Krampera, František, and Ludvík Beránek. "Kinetics of individual reactions in reaction network 1-butanol-di-(1-butyl) ether-butenes-water on alumina." Collection of Czechoslovak Chemical Communications 51, no. 4 (1986): 774–85. http://dx.doi.org/10.1135/cccc19860774.

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The complex system of six reactions occurring when 1-butanol is dehydrated on alumina at 260 °C was investigated. Initial kinetics of 1-butanol, di-(1-butyl) ether and 1-butene transformations were analyzed and best fitting rate equations for all reactions were selected. The inhibiting effects of water on initial rates was quantitatively expressed. Very low conversion data provided additional evidence for the validity of the parallel-consecutive reaction network of alcohol dehydration. In all the alkene-forming reactions, 1-butene was the primary product which was then isomerized into a mixture of cis- and trans-2-butenes.

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18

Sánchez-García, José-Luis, Brent E. Handy, Ilse N. Ávila-Hernández, Angel G. Rodríguez, Ricardo García-Alamilla, and Maria-Guadalupe Cardenas-Galindo. "Structure, Acidity, and Redox Aspects of VOx/ZrO2/SiO2 Catalysts for the n-Butane Oxidative Dehydrogenation." Catalysts 10, no. 5 (2020): 550. http://dx.doi.org/10.3390/catal10050550.

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ZrOx/SiO2 and VOx/ZrOx/SiO2 catalysts (5 wt %–25 wt % Zr, 4 wt % V) were prepared by grafting zirconium and vanadium alkoxides on Aerosil 380. All samples were characterized by temperature programmed reduction, N2 physisorption, X-ray diffraction, Raman spectroscopy, and ammonia adsorption microcalorimetry. Tetragonal ZrO2 and zircon (ZrSiO4) were present at 25 wt % Zr, but only amorphous zirconia overlayer existed for lower loadings. At lower Zr loadings (5 wt %–10 wt % Zr), exposed silica surface leads to V2O5 crystallites and isolated VO4 species, although V reducibility behavior changes, from being similar to VOx/SiO2 (5 wt % Zr) to showing VOx/ZrO2 behavior at 10 wt % Zr, and a diminished total amount of reducible V. Highly acidic ZrO2 sites are covered by the vanadium grafting, forming weaker sites (60–100 kJ/mol NH3 adsorption strength). Catalytic conversion and selectivity for the oxidative dehydrogenation of n-butane (673 K, n-C4/O2 = 2.2) over VOx/ZrOx/SiO2 show that 1,3-butadiene is favored over cis-2-butene and trans-2-butene, although there is some selectivity to the 2-butenes when VOx/ZrO2 behavior is evident. At low Zr loadings, butadiene formed during reaction acts as the diene species in a Diels–Alder reaction and gives rise to a cyclic compound that undergoes further dehydrogenation to produce benzaldehyde.

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Rode, C. V., P. R. Tayade, J. M. Nadgeri, R. Jaganathan, and R. V. Chaudhari. "Continuous Hydrogenation of 2-Butyne-1,4-diol to 2-Butene- and Butane-1,4-diols." Organic Process Research & Development 10, no. 2 (2006): 278–84. http://dx.doi.org/10.1021/op050216r.

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20

Agaguseynova, Minira M., Gunel I. Amanullayeva, and Zehra E. Bayramova. "CATALYSTS OF OXIDATION REACTION OF BUTENE-1 TO METHYLETHYLKETONE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, no. 2 (2018): 53. http://dx.doi.org/10.6060/tcct.20186102.5693.

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The available and simple metal complex systems of catalytic oxidation of unsaturated hydrocarbons were developed. It is shown that these systems catalyze the selective liquid-phase oxidation of butene-1 to methyl ethyl ketone by molecular oxygen at low temperature. The best results were revealed using Cu(I)Cl monovalent chloride. The catalyst for the production of methylethylketone is a binary system containing complexes of copper and palladium chloride at a molar ratio of 2:1. Hexamethylphosphoramide is used as the ligand and palladium chloride complex as an additional complex contains benzonitrile. A combined catalyst has been offered. It allows to carry out the oxidation reaction of butene to methyl ethyl ketone under mild conditions (low temperature, atmospheric pressure) with high selectivity and yield of the desired product. The proposed binary system is able to coordinate molecular oxygen and butene-1, and thus it becomes possible to conduct the oxidation reaction not directly between butene-1 and O2, and using a specific complex catalyst system allowing them to react with each other in an activated coordinated state. Absorption properties of catalysts synthesized on the bases of transition metals have been studied and activation of molecular oxygen and butane-1 has been determined. As a result of interaction of coordinated oxygen and butane-1 it is possible to carry out oxidation reaction to methylethylketone in mild condition. The specific feature of the offered binary catalyst is irreversible absorption of molecular oxygen. Mild conditions of the reaction proceeding decreases considerably amount of by-products and simplify obtaining and separation of the main product-methylethylketone. Due to the fact that the absorption of O2 is irreversible and it is possible to easily remove the excess amount of O2 after the formation of the oxygen complex. The developed method has the advantage from the point of view of safety.Forcitation:Agaguseynova M.M., Amanullayeva G.I., Bayramova Z.E. Catalysts of oxidation reaction of butene-1 to methylethylketone. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 53-57

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Dyson, Paul J., David J. Ellis, and Thomas Welton. "A temperature-controlled reversible ionic liquid - water two phase - single phase protocol for hydrogenation catalysis." Canadian Journal of Chemistry 79, no. 5-6 (2001): 705–8. http://dx.doi.org/10.1139/v01-084.

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An ionic liquid water system that undergoes a reversible two phase single phase transformation dependent upon temperature has been used as a novel medium for the transition-metal-catalyzed hydrogenation of a water soluble substrate. At room temperature, the ionic liquid 1-octyl-3-methylimidizolium tetrafluoroborate, containing [Rh(η4-C7H8)(PPh3)2][BF4] catalyst, forms a separate layer to water containing 2-butyne-1,4-diol. In a stirred autoclave the mixture was pressurized with hydrogen to 60 atm (1 atm = 101.325 kPa) and heated to 80°C giving a homogeneous single phase solution. On cooling to room temperature, two phases reform, with the ionic liquid phase containing the catalyst and the aqueous phase containing a mixture of 2-butene-1,4-diol and butane-1,4-diol products that can be simply removed without catalyst contamination.Key words: ionic liquids, biphasic catalysis, hydrogenation, rhodium.

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MANZANARES I., C., V. M. BLUNT, and J. PENG. "ChemInform Abstract: Spectroscopy of C-H Stretching Vibrations of Gas-Phase Butenes: cis-2- Butene, trans-2-Butene, 2-Methyl-2-butene, and 2,3-Dimethyl-2-butene." ChemInform 24, no. 32 (2010): no. http://dx.doi.org/10.1002/chin.199332030.

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23

Haimi, Piia, Petri Uusi-Kyyny, Juha-Pekka Pokki, Minna Pakkanen, and Kari I. Keskinen. "Vapour–liquid equilibrium for the ethyl ethanoate+1-butene, +cis-2-butene, +trans-2-butene, +2-methylpropene, +n-butane and +2-methylpropane." Fluid Phase Equilibria 230, no. 1-2 (2005): 21–28. http://dx.doi.org/10.1016/j.fluid.2004.10.023.

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Dell’Era, Claudia, Juha-Pekka Pokki, Petri Uusi-Kyyny, Minna Pakkanen, and Ville Alopaeus. "Vapour–liquid equilibrium for the systems diethyl sulphide+1-butene, +cis-2-butene, +2-methylpropane, +2-methylpropene, +n-butane, +trans-2-butene." Fluid Phase Equilibria 291, no. 2 (2010): 180–87. http://dx.doi.org/10.1016/j.fluid.2010.01.006.

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Hemer, Ivan, Věra Moravcová, and Václav Dědek. "Reaction of 1,4-dibromohexafluoro-2-butene with O- and N-nucleophiles." Collection of Czechoslovak Chemical Communications 53, no. 3 (1988): 619–25. http://dx.doi.org/10.1135/cccc19880619.

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Reaction of 1,4-dibromohexafluoro-2-butene (I) with sodium methoxide, ethoxide or isopropoxide in the corresponding alcohols proceeds with allylic rearrangement under formation of 3-alkoxy-4-bromohexafluoro-1-butenes II-IV. A kinetic study has proven the SN2’ mechanism for reaction of I with potassium phenoxide leading to 4-bromo-3-phenoxyhexafluoro-1-butene (V). Also the reaction of I with ammonia, affording 3-amino-4-bromo-2,4,4-trifluoro-2-butenenitrile (IX), is compatible with the allylic rearrangement by SN2’ mechanism. On the contrary, reaction of I with diethylamine gave no rearrangement product and, after hydrolysis, afforded N,N-diethyl-4-bromo-2,3,3,4,4-pentafluorobutanamide (XVI) and N,N-diethyl-4-bromo-2,3,4,4-tetrafluoro-2-butenamide (XVII) in the ratio 85:15.

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26

Guan, Jiwen, Roshan Daljeet, and Yang Song. "Pressure-selected reactivity between 2-butyne and water induced by two-photon excitation." Canadian Journal of Chemistry 95, no. 11 (2017): 1212–19. http://dx.doi.org/10.1139/cjc-2017-0155.

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High-pressure photochemistry between 2-butyne (H3CC≡CCH3) and trace amount of H2O was investigated at room temperature using multiline UV radiation at λ ≈ 350 nm and monitored by FTIR spectroscopy. Instead of the expected polymerization of 2-butyne, the IR spectral analysis suggests the formation of cis- and trans-2-butene, as well as 2-butanone, as the primary products. The possible reaction mechanisms and production pathways of these products were examined, where the dissociation of water molecule as the other reactant is believed as the essential step of the photochemical reaction. We further found that initial loading pressure of the mixture can not only substantially influence the reaction kinetics, but also regulate the accessibilities to some reaction channels, which was evidenced by quantitative analysis of the characteristic IR bands of 2-butene and 2-butanone. The relative abundance of two products is found to be highly dependent on pressure and radiation time. This study provides attractive physical routes in the absence of solvents, catalysts, and radical initiators, to synthesis the relevant products with a great selectivity and feasibility.

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27

Seo, Hyun, Jong Kwon Lee, Ung Gi Hong та ін. "Direct Dehydrogenation of n-Butane Over Pt/Sn/Zn/γ-Al2O3 Nano-Catalyst: Effect of Zn Content". Journal of Nanoscience and Nanotechnology 15, № 10 (2015): 8318–23. http://dx.doi.org/10.1166/jnn.2015.11243.

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A series of Pt/Sn/XZn/γ-Al2O3 nano-catalysts with different Zn content (X = 0, 0.25, 0.5, 0.75, and 1.0 wt%) were prepared by a sequential impregnation method. They were applied to the direct dehydrogenation of n-butane to n-butene and 1,3-butadiene. The effect of zinc content of Pt/Sn/XZn/γ-Al2O3 nano-catalysts on their physicochemical properties and catalytic activities in the direct dehydrogenation of n-butane was investigated. The catalytic performance of Pt/Sn/XZn/γ-Al2O3 nano-catalysts strongly depended on zinc content. Among the catalysts tested, Pt/Sn/0.5Zn/γ-Al2O3 nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butene and 1,3-butadiene). TPR (temperature-programmed reduction) and H2-chemisorption experiments were carried out to measure metal-support interaction and Pt surface area of the catalysts. Experimental results revealed that metal-support interaction and Pt surface area of the catalysts were closely related to the catalytic performance. Yield for TDP increased with increasing metal-support interaction and Pt surface area of the catalysts.

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28

Soficheva, О. S., G. E. Bekmukhamedov та D. G. Yakhvarov. "Catalytic Synthesis of Butene-1 and Hexene-1 in the Homogeneous Oligomerization of Ethylene in the Presence of Nickel Complexes Based on N-Heteroaryl-Substituted α-Diphenylphosphinoglycines". Кинетика и катализ 65, № 1 (2024): 12–21. http://dx.doi.org/10.31857/s0453881124010029.

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It has been experimentally shown that N-heteroaryl-substituted α-diphenylphosphinoglycines N-(pyrazin-2-yl)-α-diphenylphosphinoglycine, N-(pyridin-2-yl)-α-diphenylphosphinoglycine and N-(pyrimidin-2-yl)-α-diphenylphosphinoglycine obtained by the reaction of three-component condensation of diphenylphosphine, the corresponding primary amine and glyoxylic acid monohydrate are capable in combination with Ni(COD)₂, where COD is cyclooctadiene-1,5, to form active forms of catalysts for selective homogeneous dimerization and trimerization of ethylene with the formation of butene-1 and hexene-1 as the main products. It has been established that the obtained organo-nickel catalytic systems provide a yield of short-chain (C₄–C₆) olefins at the level of 90% with a selectivity for linear α-olefins of 97%. The study of the influence of temperature on the process of homogeneous ethylene oligomerization using the obtained compounds made it possible to establish that the optimal temperature for ethylene oligomerization, providing the highest selectivity to butene-1 and hexene-1, is 80–105°C at the optimum pressure of ethylene is 20–35 atm. Under these conditions, the selectivity for butenes is 71.4–72.6% (selectivity for butene-1 – 69.3–71.1%), for hexenes 20.6–21.2% (selectivity for hexene-1 – 19.2–19.5%), and the optimal duration of the oligomerization process at a temperature 105°C is 1.5 h, which provides the rate of formation of butene-1 equal to 168.1 golig gNi⁻¹h⁻¹) and the rate of formation of hexene-1 – 47.3 golig gNi⁻¹h⁻¹).

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29

Pasanen, Matti, Petri Uusi-Kyyny, Juha-Pekka Pokki, Minna Pakkanen, and Juhani Aittamaa. "Vapor−Liquid Equilibrium for 1-Propanol + 1-Butene, +cis-2-Butene, + 2-Methyl-propene, +trans-2-Butene, +n-Butane, and + 2-Methyl-propane." Journal of Chemical & Engineering Data 49, no. 6 (2004): 1628–34. http://dx.doi.org/10.1021/je049959i.

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30

You, Nansuk, Jin-Heong Yim, Seong Jun Lee, Jae Ho Lee, Young-Kwon Park, and Jong-Ki Jeon. "Positional Isomerization of Butene-2 over Nanoporous MCM-48 Catalysts." Journal of Nanoscience and Nanotechnology 7, no. 11 (2007): 3800–3804. http://dx.doi.org/10.1166/jnn.2007.042.

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Positional isomerization of butene-2 to butene-1 was investigated over nanoporous MCM-48 catalysts. The effects of the method and the amount of aluminum incorporation into MCM-48 on the catalyst characteristics were studied, with respect to the butene-2 isomerization reaction. Incorporation of aluminum into MCM-48 using a post-synthetic grafting method (P) or direct sol–gel method (D) increases the total acid amount due to the increase in the Lewis acidity level. From the results of butene-2 isomerization, the yield of butene-1 was increased although the selectivity of butene-1 was decreased due to an increase of byproducts such as i-butene, cracked fraction, and C5+ hydrocarbons. This trend is nearly identical over both catalyst preparation methods; the effect of Al incorporation method on the butene-1 yield and the selectivity appeared negligible. The maximum yield of butene-1 was 27.1 wt% by feeding pure butene-2 in the reaction condition as follows: a temperature of 450 °C, atmospheric pressure, and with the WHSV at 70 h−1.

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31

Boretskaya, A. V., I. R. Il’yasov, and A. A. Lamberov. "Structural and Electron Properties of High-Disperse Particles of the Active Component of Pd/Al2O3 Catalysts for Hydrogenation of Butadiene-1,3." Kataliz v promyshlennosti 19, no. 2 (2019): 114–22. http://dx.doi.org/10.18412/1816-0387-2019-2-114-122.

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Studies of the influence of acidity of alumina supports on properties of supported palladium particles were aimed at improving the activity of catalysts for hydrogenation of unsaturated hydrocarbons of pyrolysis gasoline fraction. High-disperse palladium particles demonstrate the high catalytic activity but their electron deficiency make them suffering from blocking with unsaturated hydrocarbons. NH3 TPR, TEM and XPS techniques were used for studying aluminopalladium catalysts; different acidities of the catalyst supports resulted from their chemical modification with various agents. The catalysts were tested for lab-scale hydrogenation of butadiene-1,3. Against the non-modified samples, the catalysts supported on modified alumina provided a lower conversion of butadiene-1,3 but a higher selectivity to butene-1. A higher conversion of butadiene-1,3 at the preserved selectivity to butene-1 and butane was observed in the presence of the catalyst supported on base-modified alumina.

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32

Zheng, Huidong, Jingjing Chen, Fangdi Wu, and Suying Zhao. "Molecular dynamics simulation on the interfacial features of supercritical 1-butene/subcritical water." Journal of Theoretical and Computational Chemistry 13, no. 08 (2014): 1450066. http://dx.doi.org/10.1142/s0219633614500667.

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We studied the interfacial features of 1-butene/water and extraction process of 2-butanol by molecular dynamics (MD) simulations. The infinite dilute diffusion coefficients of 1-butene in water is larger than that of 2-butanol, and one important reason is that 2-butanol molecules can form hydrogen bonds with water molecules. 1-butene is more soluble in water under supercritical condition than that under subcritical condition. 1-butene under supercritical condition can extract more 2-butanol from aqueous solution than that under other conditions. A process of producing 2-butanol by the direct hydration of 1-butene is more competive when it operates under the supercritical conditions of 1-butene which due to a higher solubility of 1-butene in water, a larger diffusion coefficient of 1-butene and a lower 2-butanol concentration in water.

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33

Wiberg, Kenneth B., Yi-gui Wang, Patrick H. Vaccaro, James R. Cheeseman, Gary Trucks, and Michael J. Frisch. "Optical Activity of 1-Butene, Butane, and Related Hydrocarbons." Journal of Physical Chemistry A 108, no. 1 (2004): 32–38. http://dx.doi.org/10.1021/jp030361b.

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34

Giroux, L., M. H. Back, and R. A. Back. "The photolysis of ethylene at 193 nm." Canadian Journal of Chemistry 67, no. 7 (1989): 1166–73. http://dx.doi.org/10.1139/v89-176.

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The photolysis of ethylene has been studied at pressures from 50 to 3000 Torr using a pulsed ArF excimer laser at 193.3 nm. Major products were acetylene, n-butane, 1-butene, ethane, and 1,3-butadiene, with smaller amounts of propane, propene, methane, and allene. Quantum yields varied with pressure and reaction time; the latter dependence is ascribed to secondary photolysis of butene and butadiene. The reaction products are accounted for by three primary processes:[Formula: see text]followed by reactions of H, [Formula: see text] and C2H5 radicals. The vibrationally excited C2H3radical can decompose to H + C2H2 or can be stabilized by collision. The pressure dependence of the quantum yields of the primary processes [1]–[3] is complex, and a photodissociation mechanism involving several intermediates and excited states of ethylene is presented to account for the present results and previous measurements at 185 nm. Keywords: ethylene, uv photolysis.

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35

Hanaoka, Toshiaki, Masaru Aoyagi, and Yusuke Edashige. "Improvement of n-Butene Yield in Dimethyl Ether-to-Olefin Reaction Using Ferrierite Zeolite Catalysts." Catalysts 13, no. 7 (2023): 1040. http://dx.doi.org/10.3390/catal13071040.

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Various ferrierite zeolites were investigated as catalysts for the dimethyl ether (DME)-to-olefin (DTO) reactions to efficiently synthesize n-butene, such as 1-butene, trans-2-butene, and cis-2-butene except for iso-butene using a fixed-bed flow reactor. Twenty P-loaded ferrierite zeolites with different structural parameters and acidic properties were prepared by the impregnation method by varying the P content and the temperature of air calcination as a pretreatment. The zeolites were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, and NH3 temperature-programmed desorption (NH3-TPD). Micropore surface area, external surface area, total pore volume, micropore volume, and weak and strong acid sites affected the DTO reaction behavior. A high n-butene yield (31.2 C-mol%) was observed, which is higher than the previously reported maximum yield (27.6 C-mol%). Multiple regression analysis showed that micropore surface area and strong acid sites had a high correlation with n-butene yield. Based on our findings, we explained the reaction mechanism for selective n-butene synthesis except for iso-butene in the DTO reaction by the dual cycle model.

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36

Hanaoka, Toshiaki, Masaru Aoyagi, and Yusuke Edashige. "n-Butene Synthesis in the Dimethyl Ether-to-Olefin Reaction over Zeolites." Catalysts 11, no. 6 (2021): 743. http://dx.doi.org/10.3390/catal11060743.

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Zeolite catalysts that could allow the efficient synthesis of n-butene, such as 1-butene, trans-2-butene, and cis-2-butene, in the dimethyl ether (DME)-to-olefin (DTO) reaction were investigated using a fixed-bed flow reactor. The zeolites were characterized by N2 adsorption and desorption, X-ray diffraction (XRD), thermogravimetry (TG), and NH3 temperature-programmed desorption (NH3-TPD). A screening of ten available zeolites indicated that the ferrierite zeolite with NH4+ as the cation showed the highest n-butene yield. The effect of the temperature of calcination as a pretreatment method on the catalytic performance was studied using three zeolites with suitable topologies. The calcination temperature significantly affected DME conversion and n-butene yield. The ferrierite zeolite showed the highest n-butene yield at a calcination temperature of 773 K. Multiple regression analysis was performed to determine the correlation between the six values obtained using N2 adsorption/desorption and NH3-TPD analyses, and the n-butene yield. The contribution rate of the strong acid site alone as an explanatory variable was 69.9%; however, the addition of micropore volume was statistically appropriate, leading to an increase in the contribution rate to 76.1%. Insights into the mechanism of n-butene synthesis in the DTO reaction were obtained using these parameters.

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37

Still, Ian W. J., та Donna Kaye T. Wilson. "α-Oxosulfines: reactions with alkenes and alkynes". Canadian Journal of Chemistry 70, № 3 (1992): 964–73. http://dx.doi.org/10.1139/v92-129.

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Thiochroman-4-one 1,1-dioxide has been successfully converted into 3-sulfinylthiochroman-4-one 1,1-dioxide and the reactions of this α-oxosulfine with a series of alkenes have been carefully investigated. The α-oxosulfine was found to react as a Diels–Alder diene with 2-methylpropene, Z- and E-2-butene, 2-ethyl-1-butene, 1-pentene, Z-2-pentene, and cyclopentene and cyclohexene to produce a new group of heterocyclic compounds, the 2,3-dihydro-5H-1,4-oxathiino[3,2-c][1]benzothiopyrans, in yields ranging from 21 to 42%. In all cases, formation of the Diels–Alder adduct was accompanied by a second type of product, identified as the product of electrophilic addition (EA) of a sulfenium species to the alkene, in lesser yields, ranging from 9 to 18%. When the trapping dienophile used was 3,3-dimethyl-1-butene, only the EA adduct was obtained, in 28% yield. Formation of only the EA type of adduct was also observed in reactions of the α-oxosulfine with 2-butyne (21%) and with the thione 2,2,4,4-tetramethylpentane-3-thione (di-tert-butyl thioketone) (16%). Attempts to prepare the α-oxosulfines corresponding to the following ketones are also described: thiochroman-4-one 1-oxide, isothiochromanone and isothiochromanone 2,2-dioxide, tetrahydrothiophen-3-one 1,1-dioxide, 3,3,5,5-tetramethylcyclohexanone, and 2-indanone. Keywords: Diels–Alder, electrophilic addition, sulfenic acid.

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38

Leigh, William J., Kangcheng Zheng, and K. Brady Clark. "Cyclobutene photochemistry. Substituent and wavelength effects on the photochemical ring opening of monocyclic alkylcyclobutenes." Canadian Journal of Chemistry 68, no. 11 (1990): 1988–97. http://dx.doi.org/10.1139/v90-305.

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The photochemical ring opening of cis- and trans-3,4-dimethyl-, 1,3,4-trimethyl-, and 1,2,3,4-tetramethylcyclobutene (1, 3, and 4, respectively) has been investigated in hydrocarbon solution with 193 nm and 214 nm light sources. Ring opening is non-stereospecific in all cases at both wavelengths. The ratio of dienes formed by the formally allowed to formally forbidden pathways in the photolysis of these compounds is highest (ca. 2) for the trimethylcyclobutenes, and approximately 1 for both cis and trans isomers of the di- and tetramethylcyclobutenes with 193 nm excitation. The diene distributions from photolysis of all compounds but cis-3 show slight wavelength dependence. Gas- and solution-phase UV absorption spectra are reported for 3 and 4, and indicate that there are at least three singlet excited states accessible in the 185–230 nm region in these molecules. The π,R(3s) state is the lowest energy state in the gas phase in 3 and 4. The results verify that orbital symmetry factors do not play a role (or a consistent one, at least) in controlling the stereochemistry of the reaction, but they do not allow a firm assignment of the excited state(s) responsible for ring opening. Direct photolysis of these compounds also results in fragmentation to yield Z-2-butene (from cis-3 and 4) or E-2-butene (from trans-3 and 4) in addition to propyne or 2-butyne. The 2-butenes are formed with greater than 90% stereospecificity in all cases. The structures of the four 3-methyl-2,4-hexadiene isomers obtained from photolysis of 3 have been assigned on the basis of 1H NMR spectroscopy and the results of thermolysis of the two cyclobutene isomers. Keywords: cyclobutene, photolysis, Rydberg, orbital symmetry, far-UV, solution phase, UV spectra.

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39

Tétényi, Pál, Tibor Szarvas, and Tamás Ollár. "Experimental proof of thiophene hydrodesulfurization reaction steps by isotope (14C) labeled thiophene." Reaction Kinetics, Mechanisms and Catalysis 134, no. 2 (2021): 697–710. http://dx.doi.org/10.1007/s11144-021-02086-6.

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AbstractHydrodesulfurization of thiophene has been studied over alumina supported sulfided molybdena, nickel-promoted molybdena and over nickel (Mo, NiMo and Ni) catalysts. The experiments were carried out with a mixture of thiophene, labeled with radioactive carbon (thiophene-[G-]-14C) and of non-radioactive tetrahydrothiophene (1:1 mol ratio) in a micro catalytic system. It was established, that the main products were tetrahydrothiophene-14C, 1-butene-14C, 2-butene-14C, butane-14C. Tetrahydrothiophene-14C was a major intermediate in the conversion of thiophene—14C in the experimental condition applied. The amounts of converted tetrahydrothiophene on the catalysts were substantially higher than those of thiophene under the same conditions. Hydrothiophene and dihydrothiophene—14C were intermediate products in the hydrodesulfurization of thiophene and tetrahydrothiophene. The hydrodesulphurization of tetrahydrothiophene was paired with dehydrogenation, producing small amounts of thiophene. The experimental results have been considered in the discussion of the mechanism of thiophene and tetrahydrothiophene desulfurization reaction pathway.

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40

Shesterkina, Anastasiya A., Anna A. Strekalova, Elena V. Shuvalova, Gennady I. Kapustin, Olga P. Tkachenko, and Leonid M. Kustov. "CuO-Fe2O3 Nanoparticles Supported on SiO2 and Al2O3 for Selective Hydrogenation of 2-Methyl-3-Butyn-2-ol." Catalysts 11, no. 5 (2021): 625. http://dx.doi.org/10.3390/catal11050625.

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In this study, novel SiO2- and Al2O3-supported Cu-Fe catalysts are developed for selective hydrogenation of 2-methyl-3-butyne-2-ol to 2-methyl-3-butene-2-ol under mild reaction conditions. TEM, XRD, and FTIR studies of adsorbed CO and TPR-H2 are performed to characterize the morphology, nanoparticle size, and particle distribution, as well as electronic state of deposited metals in the prepared catalysts. The deposition of Fe and Cu metal particles on the aluminum oxide carrier results in the formation of a mixed oxide phase with a strong interaction between the Fe and Cu precursors during the calcination. The highly dispersed nanoparticles of Fe2O3 and partially reduced CuOx, with an average size of 3.5 nm and with strong contact interactions between the metals in 5Cu-5Fe/Al2O3 catalysts, provide a high selectivity of 93% toward 2-methyl-3-butene-2-ol at complete conversion of the unsaturated alcohol.

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41

Arnold, Donald R., and Shelley A. Mines. "Radical ions in photochemistry. 21. The photosensitized (electron transfer) tautomerization of alkenes; the phenyl alkene system." Canadian Journal of Chemistry 67, no. 4 (1989): 689–98. http://dx.doi.org/10.1139/v89-105.

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Alkenes, conjugated with a phenyl group, can be converted to nonconjugated tautomers by sensitized (electron transfer) irradiation. For example, irradiation of an acetonitrile solution of the conjugated alkene 1-phenylpropene, the electron accepting photosensitizer 1,4-dicyanobenzene, the cosensitizer biphenyl, and the base 2,4,6-trimethylpyridine gave the nonconjugated tautomer 3-phenylpropene in good yield. Similarly, 2-methyl-1-phenylpropene gave 2-methyl-3-phenylpropene, and 1-phenyl-1-butene gaveE- and Z-1-phenyl-2-butene. The reaction also works well with cyclic alkenes. For example, 1-phenylcyclohexene gave 3-phenylcyclohexene, and 1-(phenylmethylene)cyclohexane gave 1-(phenylmethyl)cyclohexene. The proposed mechanism involves the initial formation of the alkene radical cation and the sensitizer radical anion, induced by irradiation of the sensitizer and mediated by the cosensitizer. Deprotonation of the radical cation assisted by the base gives the ambident radical, which is then reduced to the anion by the sensitizer radical anion. Protonation of the ambident anion at the benzylic position completes the sequence. Reprotonation at the original position is an energy wasting step. Tautomerization is driven toward the isomer with the higher oxidation potential, which is, in the cases studied, the less thermodynamically stable isomer. The regioselectivity of the deprotonation step is dependent upon the conformation of the allylic carbon–hydrogen bond. The tautomerization of 2-methyl- 1-phenylbutene gave both 2-phenylmethyl-1-butène and 2-methyl-1-phenyl-2-butene (E and Z isomers), while 2,3-dimethyl- 1-phenylbutene gave only 3-methyl-2-phenylmethyl-1 -butene. In the latter case, steric interaction of the methyls on the isopropyl group prevents effective overlap of the tertiary carbon–hydrogen bond with the singly occupied molecular orbital, thus inhibiting deprotonation from this site. Keywords: photosensitized, electron transfer, alkene, tautomerization, radical cation.

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42

Faghihian, H., and M. Pirouzi. "Cis/trans-but-2-ene adsorption on natural and modified clinoptilolite." Clay Minerals 44, no. 3 (2009): 405–9. http://dx.doi.org/10.1180/claymin.2009.044.3.405.

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AbstractAdsorption of cis-2-butene and trans-2-butene on clinoptilolite-rich tuff and ion-exchanged forms was investigated. Clinoptilolite samples were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, chemical analysis and nitrogen adsorption techniques. Adsorption isotherms for cis and trans 2-butene on purified clinoptilolite (Cp) and modified forms (Na-Cp, K-Cp, Ca-Cp and Mg-Cp) were obtained at pressures up to 2.7 atm. and at 25ºC. The results show that natural clinoptilolite has a considerable potential for separation of the two hydrocarbons. Mg-Cp samples showed maximal uptake of both cis-2-butene and trans-2-butene.

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43

Pérez Oliveros, Jaime Olmedo, and Bibiana del Carmen Molina García. "1-Butanol dehydration as catalytic test to determine acidity of solid acids." Revista Facultad de Ingeniería Universidad de Antioquia, no. 33 (October 31, 2005): 7–20. http://dx.doi.org/10.17533/udea.redin.344283.

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Catalytic dehydration of 1-Butanol was used as a test reaction to determine the nature of acid sites on several samples: undoped and doped sulfated-zirconia (dopants: Ce, W, or Sb), ZSM-5, Al-MCM-41 and permutite (amorphous aluminosilicate). Acid strength for each sample was ranked according to its catalytic activity. Catalysts exhibiting similar activity can be compared by the isomer ratios: cis-butene/trans-butene (CB/TB), 1-butene/trans-butene (1B/TB), and isobutene/ trans-butene (IB/TB). It was found that the activity of the sulfated-zirconia was directly proportional to the sulfate content. Interestingly, Al-MCM-41 exhibits similar acidity to the best sulfated-zirconia sample.

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44

Van Ginkel, C. G., H. G. J. Welten, S. Hartmans, and J. A. M. De Bont. "Metabolism of trans-2-Butene and Butane in Nocardia TB1." Microbiology 133, no. 7 (1987): 1713–20. http://dx.doi.org/10.1099/00221287-133-7-1713.

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45

Rakhimov, M. N., T. M. Beloklokova, Zh F. Galimov, and A. V. Pankratov. "Stability of properties of catalysts for butane-butene fraction oligomerization." Chemistry and Technology of Fuels and Oils 34, no. 6 (1998): 379–81. http://dx.doi.org/10.1007/bf02694127.

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46

Cui, Peng, Guoying Zhao, Hailing Ren, Jun Huang, and Suojiang Zhang. "Ionic liquid enhanced alkylation of iso-butane and 1-butene." Catalysis Today 200 (February 2013): 30–35. http://dx.doi.org/10.1016/j.cattod.2012.06.008.

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47

Kotov, S. V., V. N. Filin, K. V. Prokof'ev, I. S. Morozova, and L. D. Kalinina. "Two-stage synthesis of oligobutenetoluenes from commercial butane-butene fraction." Chemistry and Technology of Fuels and Oils 27, no. 4 (1991): 188–90. http://dx.doi.org/10.1007/bf01129513.

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48

Strazdaite, Simona, Ruta Bariseviciute, Justinas Ceponkus, and Valdas Sablinskas. "Conformational isomerism of 1-butene secondary ozonide as studied by means of matrix isolation infrared absorption spectroscopy." Open Chemistry 10, no. 5 (2012): 1647–56. http://dx.doi.org/10.2478/s11532-012-0077-3.

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AbstractTheoretical calculations of structures, stability and vibrational spectra of 1-butene secondary ozonide (SOZ) conformers were performed using DFT method B3LYP with a 6-311++G(3df, 3pd) basis set. The calculations predict six staggered structures of 1-butene SOZ. The FTIR spectra of 1-butene SOZ isolated in Ar, N2 and Xe matrices were recorded. It was found that nitrogen is the best suited for the matrix isolation of 1-butene SOZ. The bandwidth of the spectral bands of the ozonide isolated in nitrogen was as narrow as 2 cm−1. For the first time the existence of five conformers of 1-butene SOZ were confirmed experimentally by means of matrix isolation infrared absorption spectroscopy. The equatorial gauche (∠OCCC=−66.1°) conformer was proved theoretically and experimentally to be the most stable. It was found that due to high potential barriers of the conformational transitions annealing of the matrix is useless for the assignment of spectral bands to various conformers of 1-butene SOZ. Using the hot nozzle technique the van’t Hoff experimental plots were made for three additional conformers of 1-butene SOZ and experimental ΔH values for these additional conformers were established. The crystallization problems of 1-butene SOZ are discussed which accounts for the rich conformational diversity of the ozonide as well as high conformational barriers for axial-equatorial transitions.

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49

WU, PING, JOHNNY TRUONG, YONGSHUN HUANG, and JIAXING LI. "REGIOSELECTIVITY INVESTIGATION FOR THE PYROLYSIS OF XANTHATES: A COMPUTATIONAL STUDY." Journal of Theoretical and Computational Chemistry 12, no. 07 (2013): 1350064. http://dx.doi.org/10.1142/s0219633613500648.

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MP2/6-31+G(d,p)//MP2/6-31G(d) method was employed to investigate the pyrolyses of O -sec-butyl S -methyl xanthate (Chugeav reaction) and S -sec-butyl O -methyl xanthate, which gave regioselective products of E-butene, Z-butene and 1-butene. Both procedures were found to have 13 possible pathways, of which nine pathways would generate the alkene products. For O -sec-butyl S -methyl xanthate, the computational results indicated that the most favorable three pathways corresponded to a two-step mechanism, with the rate-determining step to be a thion sulfur atom involved six-membered ring transition states. The calculated products distribution was consistent with the experimental observations. However, for S -sec-butyl O -methyl xanthate, thiol-participated four-membered ring transition states were found to be more energetically favored than the six-membered ring transition state to produce 1-butene, which can be attributed to a larger sulfur atomic size than an oxygen atom. As the calculation result, only trace amount of 1-butene could be obtained with a major product being E-butene and Z-butene as a minority.

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Xia, Jingjing, Abdullah M. Asiri, Khalid A. Alamry, Ping Wu, and Zhihao Huang. "Pyrolysis of (thio)carbonates via computation analysis." Journal of Theoretical and Computational Chemistry 17, no. 06 (2018): 1850041. http://dx.doi.org/10.1142/s0219633618500414.

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The regioselective production of alkenes from (thio)carbonates was calculated by MP2/6-31G(d) method via pyrolysis processes. Four (thio)carbonates were calculated in this paper. They are S-sec-butyl O-methyl thiocarbonate (I), O-sec-butyl S-methyl thiocarbonate (II), sec-butyl methyl thioncarbonate (III), and sec-butyl methyl dithiocarbonate (IV). Thirteen potential thermolysis routes were revealed for the pyrolysis of each substance, including nine routes to produce regioselective alkenes and four rearrangement/decompose alternatives. Among nine alkene generation routes, six-membered ring transition states via a two-step mechanism required the lowest energy, while the other routes exhibited higher energy barriers. The calculation results demonstrated an alkene distribution hierarchy of 1-butene [Formula: see text] E-butene [Formula: see text] Z-butene for substances I and II, and an order of E-butene [Formula: see text] 1-butene [Formula: see text] Z-butene for substances III and IV.

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Journal articles on the topic 'Butene'

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