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Enabling tandem oxidation of benzene to benzenediol over integrated neighboring V-Cu oxides in mesoporous silica
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作者 Mengting Liu Xuexue Dong +3 位作者 Zengjing Guo Aihua Yuan Shuying Gao Fu Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期236-245,共10页
The direct tandem oxidation synthesis of benzenediol from benzene could simplify or even avoid the separation and purification of reaction intermediates, which is promising but challenged because of the further requir... The direct tandem oxidation synthesis of benzenediol from benzene could simplify or even avoid the separation and purification of reaction intermediates, which is promising but challenged because of the further required immediate consecutive activation of intermediate phenol. In this work, a synergistic benzene tandem-oxidation catalyst that V-Cu bimetallic oxides modified nanoporous silica(VCu-NS)was constructed via a facile assembly strategy which involves addictive negative anion citric acid mediating the intercalation of metal-citric acid chelate in mesopore of silica and subsequent thermal calcination inducing dual-metal active site formation. Such a tactic could make amorphous VOxspecies well covered on the surface of mesopore, and ultrafine copper oxide particles surrounded and neighbored by highly dispersed VOxwith strong interplay in mesopore, which was comprehensively confirmed by various characterizations. Benefiting from the unique V-Cu neighboring effect, the desorption of formed phenol over the catalytic site might be restricted therefore easily further activated by the formed reactive oxidative species, 3VCu-NS shows synergetic tandem-oxidation catalytic activities for benzene towards benzenediol with a selectivity of 57%. The result allows optimal 3VCu-NS to be a promising catalyst for benzenediol synthesis from benzene. 展开更多
关键词 CATALYSIS Molecular sieve benzene Synergetic effect Tandem oxidation
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Understanding the interfacial behaviors of benzene alkylation with butene using chloroaluminate ionic liquid catalyst: A molecular dynamics simulation
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作者 Jialei Sha Chenyi Liu +3 位作者 Zhihong Ma Weizhong Zheng Weizhen Sun Ling Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期44-52,共9页
To better understand the benzene alkylation with chloroaluminate ionic liquids(ILs) as catalyst, the interfacial properties between the benzene/butene binary reactants and chloroaluminate ILs with varying cation alkyl... To better understand the benzene alkylation with chloroaluminate ionic liquids(ILs) as catalyst, the interfacial properties between the benzene/butene binary reactants and chloroaluminate ILs with varying cation alkyl chain length and different anions were investigated using molecular dynamics(MD) simulations. The results indicate that ILs can obviously improve the interfacial width, solubility and diffusion of reactants compared to H_(2)SO_(4). The longer alkyl chains of cations present a density enrichment at the interface and protrude into the binary reactants phase. Furthermore, the ILs consisting of 1-octyl-3-methylimidazolium cations([Omim]^(+)) and the stronger acidity heptachlorodialuminate anions([Al_(2)Cl_(7)]^(-)) are more beneficial to promote the interfacial width and facilitate the dissolution and diffusion of benzene in both the IL bulk and the interfacial region in comparison to the ones with shorter alkyl chains cations and weaker acidity anions. The information gives us a better guideline for the design of ILs for benzene alkylation. 展开更多
关键词 benzene alkylation Interfacial behaviors Ionic liquids Molecular dynamics simulation
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Benzene and Toluene Levels Measured with DOAS During Vehicular Restrictions in Beijing 被引量:3
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作者 李素文 谢品华 +1 位作者 韦民红 王江涛 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期119-122,I0002,共5页
Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The... Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The correlations between traffic flows and totals of benzene and toluene were studied during the period of vehicular traffic restrictions from August 17 to August 20 and non-traffic restrictions on August 16 and August 21. The correlation coef- ficient was 0.8 between benzene and toluene. And the calculated daily mean value ratios of benzene to toluene were 0.43-0.50. During the period of vehicular restrictions, traffic flows were reduced about 11.8% and the levels of benzene and toluene were reduced by 11.4% and 12.8%, respectively. The vehicle emissions were recognized as the major sources for atmospheric benzene and toluene in Beijing. 展开更多
关键词 Differential optical absorption spectroscopy benzene and toluene Vehicularrestrictions Tramc emissions Traffic flows
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Effect of Excited-state Substituent Constant on the UV Spectra of 1,4-disubstituted Benzenes 被引量:9
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作者 陈冠凡 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期366-370,447,共6页
A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coeffici... A correlation equation between the UV absorption wavenumbers of 1,4-disubstituted benzenes and the excited-state substituent constant was obtained. For 80 sorts of 1,4- disubstituted benzenes, the correlation coefficient was 0.9805, and the standard deviation was only 672.27 cm^-1. The results imply that the excited-state substituent constant can be used productively for research on UV energy of 1,4-disubstituted benzenes. The present method provides a new avenue to study the UV absorption spectra of aromatic systems with the excited-state substituent constant, and it is helpful to understand the effect of substituent electrostatic effects on the chemical and physical properties of conjugated compounds with multiple substituents in excited state. 展开更多
关键词 Excited-state substituent constant 1 4-disubstituted benzene UV absorption wavenumber Interaction of substituent
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Photoionization Mass Spectrometric and Kinetic Modeling of Low-pressure Pyrolysis of Benzene 被引量:2
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作者 杨玖重 赵龙 +2 位作者 蔡江淮 齐飞 李玉阳 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第3期245-251,I0003,共8页
Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomer... Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomers and polycyclic aromatic hydrocarbons, and measure their mole fraction profiles versus temperature. A low-pressure pyrolysis model of benzene was developed and validated by the experimental results. Rate of production analysis was performed to reveal the major reaction networks in both fuel decomposition and aromatic growth processes. It is concluded that benzene is mainly decomposed via H-abstraction reaction to produce phenyl and partly decomposed via unimolecular decomposition reac- tions to produce propargyl or phenyl. The decomposition process stops at the formation of acetylene and polyyne species like diacetylene and 1,3,5-hexatriyne due to their high thermal stabilities. Besides, the aromatic growth process in the low-pressure pyrolysis of benzene is concluded to initiate from benzene and phenyl, and is controlled by the even carbon growth mechanism due to the inhibited formation of C5 and C7 species which play important roles in the odd carbon growth mechanism. 展开更多
关键词 benzene Low-pressure pyrolysis PAH formation Synchrotron vacuum ultra-violet photoionization mass spectrometry Kinetic model
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A Durable Catalyst for Vapor Phase Nitration of Benzene with Nitric Acid 被引量:1
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作者 Peng ZHOU Xin Ping WANG Tian Xi CAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期1013-1016,共4页
Experimental results in this work demonstrate that PW12-H2SO4/SiO2 catalyst is a good and durable catalyst for vapor phase nitration of benzene to nitrobenzene (NB) using 65% nitric acid at normal pressure. It retains... Experimental results in this work demonstrate that PW12-H2SO4/SiO2 catalyst is a good and durable catalyst for vapor phase nitration of benzene to nitrobenzene (NB) using 65% nitric acid at normal pressure. It retains the advantages of using H2SO4 as catalyst and the addition of phosphotungstic acid holds back the effusion of sulfuric acid. This new catalyst keeps high activity (the conversion of HNO3 is more than 92%), high selectivity of NB (more than 97%) and high space time yield (STY 1.5 kg NB/kg cat.h) even after 150 h on stream, under condition of 423 K, SV=3200 ml/g h. 展开更多
关键词 NITRATION benzene solid acid nitric acid nitrobenzene.
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Vanadium supported on graphitic carbon nitride as a heterogeneous catalyst for the direct oxidation of benzene to phenol 被引量:10
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作者 王成 胡丽雅 +3 位作者 王美银 任远航 岳斌 贺鹤勇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期2003-2008,共6页
A series of graphitic carbon nitride supported vanadium catalysts(xV/g-C3N4) with different vanadium contents(x/%) were prepared by impregnation.XRD,FT-IR,TEM,TG-DTG,nitrogen adsorption and XPS characterizations w... A series of graphitic carbon nitride supported vanadium catalysts(xV/g-C3N4) with different vanadium contents(x/%) were prepared by impregnation.XRD,FT-IR,TEM,TG-DTG,nitrogen adsorption and XPS characterizations were conducted which revealed a strong interaction between the vanadium species and g-C3N4 support.8V/g-C3N4 exhibited the highest activity and showed stable recyclability in the benzene hydroxylation reaction with a benzene conversion of 24.6%and phenol selectivity of 99.2%under the optimized conditions.The excellent catalytic performance of xV/g-C3N4 was due to the integration of vanadium species with high catalytic activity and the g-C3N4support in their interaction with the benzene substrate. 展开更多
关键词 Carbon nitride VANADIUM benzene hydroxylation PHENOL IMPREGNATION
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Adsorption of Benzene on the Potassium Exchanged Hbeta Zeolites
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作者 SHEN Jian-ping MA Jun SUN Tie and JIANG Da-zhen(Department of Chemistry, Jilin University, Changchun , 130023)MIN En-ze(Research Institute of Petroleum Processing, Beijing, 100083) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第2期120-125,共6页
n situ iR studies of benzene adsorbed on different potassium-exchanged degrees of KHβ zeolites were carried out under different conditions. The bands of adsorbed benzene on KHβ zeolites in the range of 2050-1750 cm-... n situ iR studies of benzene adsorbed on different potassium-exchanged degrees of KHβ zeolites were carried out under different conditions. The bands of adsorbed benzene on KHβ zeolites in the range of 2050-1750 cm-1 were assigned.The KHβ zeolite has basicity only when the ratio of K to AI of KHβ is up to88. 39%, its basicity is stronger and its acidity is weaker. The order of stability ofthe adsorbed benzene species on the samples is O>H>K>b. 展开更多
关键词 ABSORPTION benzene. Zeolite
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Assessment of Some Density Functional Theory Methods and Force Field Models in Describing Various Interaction Modes of Benzene Dimer 被引量:1
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作者 周余伟 张颖 +2 位作者 吴剑鸣 吴安安 徐昕 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第6期635-639,I0003,共6页
Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some m... Benzene dimer (bz2) is the simplest prototype of the π-π interactions. Such interactions are ubiquitous in diverse areas of science and molecular engineering. In the present work, we have made assessment on some modern density functional methods including B97-D, BLYP-D3, M06-2X, XYG3, and force field models including CHARMM, AMBER, MM3, AMOEBA on six important interaction modes of bz2. Our results not only highlight the usefulness of these cost-effective methods, which can be used as economic substitutes of the expensive CCSD(T) for complex real-world systems, but also indicate their weakness in the description of the π-π interactions, which points to the future direction for further improvements. 展开更多
关键词 π-π interaction benzene dimer van der Waals DISPERSION XYG3
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Production of Benzene from Lignin through Current Enhanced Catalytic Conversion 被引量:1
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作者 吴小平 范明慧 李全新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期479-486,I0002,共9页
The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective r... The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective recombinant of the functional groups in the aromatic monomers. A high benzene yield of 175 gbenzene/kglignin was obtained with an excellent selectivity of 92.9 C-mol%. The process potentially provides a promising route for the production of basic petrochemical materials or high value-added chemicals using renewable biomass. 展开更多
关键词 benzene Current enhanced catalytic conversion LIGNIN ZEOLITE
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Light-Induced Reaction of Benzene with Carbonates
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作者 姬铭松 董春华 +1 位作者 张华烨 杨新征 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第3期319-324,I0001,共7页
We found an ultraviolet (UV)-light induced formation of biphenyl and sodium benzoate from benzene and sodium carbonate. The reaction happens in the interface of benzene and aqueous solution at the room temperature. ... We found an ultraviolet (UV)-light induced formation of biphenyl and sodium benzoate from benzene and sodium carbonate. The reaction happens in the interface of benzene and aqueous solution at the room temperature. After 5 h of UV-light exposure, 11.4% of initial amount of 4.4 g (5.0 mL) benzene are converted to biphenyl and sodium benzoate, which are distributed in benzene and aqueous solution, respectively. Using density function theory (DFT) and time dependent DFT, we have investigated the mechanism of this light-induced reaction, and found that the sodium carbonate is not only a reactant for the formation of sodium benzoate, but also a catalyst for the formation of biphenyl. 展开更多
关键词 benzene CARBONATES Light-induced reaction Density function theory calcu-lation MECHANISM
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Benzene alkylation with methanol over phosphate modified hierarchical porous ZSM-5 with tailored acidity 被引量:15
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作者 Jinghui Lyu Hualei Hu +7 位作者 Carolyn Tait Jiayao Rui Caiyi Lou Qingtao Wang Wenwen Han Qunfeng Zhang Zhiyan Pan Xiaonian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第9期1187-1194,共8页
The acidity and acid distribution of hierarchical porous ZSM-5 were tailored via phosphate modification. The catalytic results showed that both benzene conversion and selectivity of toluene and xylene increased with t... The acidity and acid distribution of hierarchical porous ZSM-5 were tailored via phosphate modification. The catalytic results showed that both benzene conversion and selectivity of toluene and xylene increased with the presence of appropriate amount of phosphorus. Meanwhile, side reactions such as methanol to olefins related with the formation of by-product ethylbenzene formation and isomerization of xylene to meta-xylene were suppressed efficiently. The acid strength and sites amount of Br?nsted acid of the catalyst were crucial for improving benzene conversion and yield of xylene, whereas passivation of external surface acid sites played an important role in breaking thermodynamic equilibrium distribution of xylene isomers. 展开更多
关键词 Hierarchical porous ZSM-5 Phosphate modification benzene alkylation with methanol XYLENE
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Water-promoted One-step Anodic Acetoxylation of Benzene to Phenyl Acetate with High Selectivity
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作者 裴娟 秦松 +1 位作者 李桂英 胡常伟 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期244-248,I0004,共6页
One-step anodic acetoxylation of benzene to phenyl acetate was studied in acetic acid-water solution using a one-compartment electrochemical cell in galvanostatic mode. Compared to the anhydrous system, the addition o... One-step anodic acetoxylation of benzene to phenyl acetate was studied in acetic acid-water solution using a one-compartment electrochemical cell in galvanostatic mode. Compared to the anhydrous system, the addition of water improved the current efficiency for the electrosynthesis of phenyl acetate. The maximum efficiency reached 4.8% with the selectivity of 96% to phenyl acetate when the electrolysis was carried out under the optimal conditions. The investigation also indicated that the concentration of phenyl acetate increased linearly in 12 h and reached 1.07 g/L with the selectivity of 95%. Cyclic voltammetry experiments showed that the adsorption of benzene at Pt anode enhanced by the addition of water was critical to the formation of phenyl acetate. An activated benzene mechanism was proposed for the anodic acytoxylation, and the analysis of gas products demonstrated that Kolbe reaction was the main side reaction. 展开更多
关键词 Anodic acetoxylation benzene Acetic acid aqueous solution Phenyl acetate Mechanism
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Distribution Coefficient of Caprolactam and Methyl Caprolactam Using Benzene or Toluene as Extractants: Experiments and Prediction 被引量:8
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作者 龚行楚 吕阳成 骆广生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期463-467,共5页
To get high purity caprolactam is a challenging task in the chemical fiber industry. To date, reports on the prediction of the distribution of caprolactam and its derivative chemicals have been few. In this study, the... To get high purity caprolactam is a challenging task in the chemical fiber industry. To date, reports on the prediction of the distribution of caprolactam and its derivative chemicals have been few. In this study, the extraction of caprolactam with toluene as the extractant and N-methyl caprolactam with benzene and toluene as theextractants has been camed out. By defining new UNIFAC groups and calibrating related interaction parameters, aUNIFAC method was introduced to predict the equilibrium concentration of caprolactam and methyl caprolactam intoluene or benzene extraction processes. The calculated results fit very well With the experimental data. Using theUNIFAC model, the selectivity of extractants can be predicted. 展开更多
关键词 extraction UNIFAC model CAPROLACTAM benzene TOLUENE
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Reaction Kinetics of Ozonation of Trichloroethylene and Benzene in Gas and Liquid Phases 被引量:8
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作者 钟理 Kuo Chiang-Hai 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第3期272-275,共4页
The kinetics of ozonation reactions of trichloroethylene (TCE) and benzene in gas and liquid phases at 101.3 kPa and 298 K was investigated in this paper. The ozonation of TCE is first order with respect to the ozone ... The kinetics of ozonation reactions of trichloroethylene (TCE) and benzene in gas and liquid phases at 101.3 kPa and 298 K was investigated in this paper. The ozonation of TCE is first order with respect to the ozone concentration and one and half order to TCE in the gas phase with the average rate constant 57.30 (mol·L-1)-1.5·s-1, and the TCE ozonation in aqueous medium is first order with respect to both ozone and trichloroethylene with the average rate constant 6.30 (mol·L-1)-1·-1. The ozonation of benzene in the gas phase is first order in ozone but independent of the benzene concentration with the average reaction rate constant 0.0011s-1. The overall kinetics of reaction between ozone and benzene in aqueous solution is found to be first order with one-half order in both ozone and bezene, with the average reaction rate constant 2.67s-1. It is found that the ozonation rate of pallutants is much quicker than that of self-decomposition of ozone in both gas and aqueous phase. 展开更多
关键词 REACTION OZONE POLLUTANT TRICHLOROETHYLENE benzene
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Highly selective ethylbenzene production through alkylation of dilute ethylene with gas phase-liquid phase benzene and transalkylation feed 被引量:11
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作者 Shenglin Liu Fucun Chen +3 位作者 Sujuan Xie Peng Zeng Xiyan Du Longya Xu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第1期21-24,共4页
A novel industrial process was designed for the highly selective production of ethylbenzene. It comprised of a reactor vessel, vapor phase ethylene feed stream, benzene and transalkylation feed stream. Especially the ... A novel industrial process was designed for the highly selective production of ethylbenzene. It comprised of a reactor vessel, vapor phase ethylene feed stream, benzene and transalkylation feed stream. Especially the product stream containing ethylbenzene was used to heat the reactor vessel, which consisted of an alkylation section, an upper heat exchange section, and a bottom heat exchange section. In such a novel reactor, vapor phase benzene and liquid phase benzene were coexisted due to the heat produced by isothermal reaction between the upper heat exchange section and the bottom heat exchange section. The process was demonstrated by the thermodynamic analysis and experimental results. In fact, during the 1010 hour-life-test of gas phase ethene with gas phase-liquid phase benzene alkylation reaction, the ethene conversion was above 95%, and the ethylbenzene selectivity was above 83% (only benzene feed) and even higher than 99% (benzene plus transalkylation feed). At the same time, the xylene content in the ethylbenzene was less than 100 ppm when the reaction was carried out under the reaction conditions of 140-185℃ of temperature, 1.6-2.1 MPa of pressure, 3.0-5.5 of benzene/ethylene mole ratio, 4-6 v% of transalkylation feed/(benzene+transalkylation feed), 0.19-0.27 h^-1 of ethene space velocity, and 1000 g of 3998 catalyst loaded. Thus, compared with the conventional ethylbenzene synthesis route, the transalkylation reactor could be omitted in this novel industrial process. 展开更多
关键词 dilute ethylene gas phase-liquid phase benzene ALKYLATION ETHYLbenzene
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Anaerobic biodegradation of benzene series compounds by mixed cultures based on optional electronic acceptors 被引量:10
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作者 HU Zhi-feng DOU Jun-feng +2 位作者 LIU Xiang ZHENG Xi-lai DENG Dong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1049-1054,共6页
A series of batch experiments were performed using mixed bacterial consortia to investigate biodegradation performance of benzene, toluene, ethylbenzene and three xylene isomers (BTEX) under nitrate, sulfate and fer... A series of batch experiments were performed using mixed bacterial consortia to investigate biodegradation performance of benzene, toluene, ethylbenzene and three xylene isomers (BTEX) under nitrate, sulfate and ferric iron reducing conditions. The results showed that toluene, ethylbenzene, m-xylene and o-xylene could be degraded independently by the mixed cultures coupled to nitrate, sulfate and ferric iron reduction. Under ferric iron reducing conditions the biodegradation of benzene and p-xylene could be occurred only in the presence of other alkylbenzenes. Alkylbenzenes can serve as the primary subs'rates to stimulate the transformation of benzene and p-xylene under anaerobic conditions. Benzene and p-xylene are more toxic than toluene and ethylbenzene, under the three terminal electron acceptors conditions, the degradation rates decreased with toluene 〉 ethylbenzene 〉 m-xylene 〉 o-xylene〉 benzene 〉 p- xylene. Nitrate was a more favorable electron acceptor compared to sulfate and ferric iron. The ratio between sulfate consumed and the loss of benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene was 4.44, 4.51, 4.42, 4.32, 4.37 and 4.23, respectively; the ratio between nitrate consumed and the loss of these substrates was 7.53, 6.24, 6.49, 7.28, 7.81, 7.61, respectively; the ratio between the consumption of ferric iron and the loss of toluene, ethylbenzene, o-xylene, m-xylene was 17.99, 18.04, 18.07, 17.97, respectively. 展开更多
关键词 benzene toluene ethylbenzene and three xylene isomers (BTEX) anaerobic biodegradation nitrate reduction sulfatereduction ferric iron reduction
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Hydroxylation of Benzene with Hydrogen Peroxide over Highly Efficient Molybdovanadophosphoric Heteropoly Acid Catalysts 被引量:8
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作者 张富民 郭麦平 +1 位作者 葛汉青 王军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期895-898,共4页
Keggin type molybdovanadophosphoric heteropoly acids, H3+nPMo12-nVnO40(n=1-3), were prepared by a novel environmentally benign method, and their catalytic performances were evaluated via hydroxylation of benzene to... Keggin type molybdovanadophosphoric heteropoly acids, H3+nPMo12-nVnO40(n=1-3), were prepared by a novel environmentally benign method, and their catalytic performances were evaluated via hydroxylation of benzene to phenol with hydrogen peroxide as oxidant in a mixed solvent of glacial acetic acid and acetonitrile. Various reaction parameters, such as reaction time, reaction temperature, ratio of benzene to hydrogen peroxide, concentration of aqueous hydrogen peroxide, ratio of glacial acetic acid to acetonitrile in solvent and catalyst con- centration, were changed to obtain an optimal reaction conditions. H3+nPMo12-nVnO40(n=1-3) are revealed to be highly efficient catalyst for hydroxylation of benzene. In case of H5PMo10V2O40, a conversion of benzene of 34.5% with the selectivity of phenol of 100% can be obtained at the optimal reaction conditions. 展开更多
关键词 HYDROXYLATION heteropoly acid PHENOL benzene
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[bmim]Cl/[FeCl3] Ionic Liquid as Catalyst for Alkylation of Benzene with 1-Octadecene 被引量:10
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作者 孙学文 赵锁奇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第3期289-293,共5页
Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB (linear alkylbenzenes) was performed. The results showed that the most important factor that governe... Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB (linear alkylbenzenes) was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene. 展开更多
关键词 ALKYLATION benzene 1-octadecene [bmim]Cl/[FeCl3] ionic liquid
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Deactivation mechanism of beta-zeolite catalyst for synthesis of cumene by benzene alkylation with isopropanol 被引量:6
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作者 Yefei Liu Yang Zou +2 位作者 Hong Jiang Huanxin Gao Rizhi Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第9期1195-1201,共7页
The alkylation of benzene with isopropanol over beta-zeolite is a more cost-effective solution to cumene production. During the benzene alkylation cycles, the cumene selectivity slowly increased, while the benzene con... The alkylation of benzene with isopropanol over beta-zeolite is a more cost-effective solution to cumene production. During the benzene alkylation cycles, the cumene selectivity slowly increased, while the benzene conversion presented the sharp decrease due to catalyst deactivation. The deactivation mechanism of betazeolite catalyst was investigated by characterizing the fresh and used catalysts. The XRD, SEM and TEM results show that the crystalline and particle size of the beta-zeolite catalyst almost remained stable during the alkylation cycles. The drop in catalytic activity and benzene conversion could be explained by the TG, BET,NH_3-TPD and GC–MS results. The organic matters mainly consisted of ethylbenzene, p-xylene and 1-ethyl-3-(1-methyl) benzene produced in the benzene alkylation deposited in the catalyst, which strongly reduced the specific surface area of beta-zeolite catalyst. Moreover, during the reaction cycles, the amount of acidity also significantly decreased. As a result, the catalyst deactivation occurred. To maintain the catalytic performance,the catalyst regeneration was carried out by using ethanol rinse and calcination. The deactivated catalyst could be effectively regenerated by the calcination method and the good catalytic performance was obtained. 展开更多
关键词 CUMENE benzene ISOPROPANOL ALKYLATION BETA-ZEOLITE Catalyst deactivation
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