JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2014
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IF 2.045
Lijuan Peng,Qinbo Wang,Binwei Shen,Chuxiong Chen,Zhenhua Xiong
Liquid–liquid equilibrium (LLE) data for the ternary system water + ethylbenzene + acetophenone and water + ethylbenzene + 1-phenylethanol were determined at temperatures T = (298.2, 308.2, 318.2, and 328.2) K and atmospheric pressure. The immiscibility region was found to be relatively small and not sensitive to the change of temperature. The Othmer–Tobias and the Bachman correlations were used to test the consistency of the LLE data. The experimental data were correlated by both the nonrandom two-liquid and the universal quasichemical activity coefficient models. The relevant model interaction parameters were regressed by data fitting. The model correlated results show good agreement with the measured data. The obtained interaction parameters can be used in the calculation of LLE for the ternary system water + ethylbenzene + acetophenone and water + ethylbenzene +1-phenylethanol as well as for the design and optimization of the related separation process.
研究领域:
化学工程
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热力学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
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2014
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IF 0
Hongyan Li,Hong Ma,Xinhong Wang,Jin Gao,Chen Chen,Song Shi,Minjie Qu,Na Feng,Jie Xu
Efficient catalytic oxidation of ethylbenzene to acetophenone was realized using the catalytic system of cobalt zeolitic imidazolate framework ZIF-67/N-hydroxyphthalimide (NHPI) under mild conditions. 95.2% conversion of ethylbenzene with 90.3% selectivity to acetophenone could be obtained at 373 K under 0.3 MPa O 2 for 9 h. The results show that there exists synergetic effect between ZIF-67 and NHPI. 1-Phenylethyl hydroperoxide (PEHP) was generated via a radical process involving the hydrogen abstraction from ethylbenzene by phthalimide N-oxyl, and subsequently effectively decomposed to acetophenone by ZIF-67.
研究领域:
催化化学
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材料科学
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产品关联
DOI
Catalysts
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2023
·Vol. 13
·期 4
·781
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IF 3.9
He Sun,Juping Zhang,Kongzhai Li,Hua Wang,Xing Zhu
HighlightsWhat are the main findings?A styrene yield of 91.4% was found for 10% k/CeO2at 500 °C and CO2-O2mixed atmosphere. The excellent catalytic performance of 10% k/CeO2is attributed to the alkali metal oxide modified cerium oxide and carbon dioxide induced oxygen vacancies to promote the dehydrogenation of ethylbenzene.What is the implication of the main finding?The proposed ODH strategy by using oxygen vacancies enriched catalysts offers an important insight into the efficient dehydrogenation of ethylbenzene at mild conditions.AbstractOxidative dehydrogenation (ODH) is an alternative for styrene (ST) production compared to the direct dehydrogenation process. However, ODH with O2or CO2suffers from either over-oxidation or endothermic property/low ethylbenzene conversion. Herein, we proposed an ODH process with a CO2-O2mixture atmosphere for the efficient conversion of ethylbenzene (EB) into styrene. A thermoneutral ODH is possible by the rationalizing of CO2/O2molar ratios from 0.65 to 0.66 in the temperature range of 300 to 650 °C. K modification is favorable for ethylbenzene dehydrogenation, and 10%K/CeO2achieved the highest ethylbenzene dehydrogenation activity due to the enhanced oxygen mobility and CO2adsorbability. The catalyst achieved 90.8% ethylbenzene conversion and 97.5% styrene selectivity under optimized conditions of CO2-4O2oxidation atmosphere, a temperature of 500 °C, and a space velocity of 5.0 h−1. It exhibited excellent catalytic and structural stability during a 50 h long-term test. CO2induces oxygen vacancies in ceria and promotes oxygen exchange between gaseous oxygen and ceria. The ethylbenzene dehydrogenation in CO2-O2follows a Mars-van Krevelen (MvK) reaction mechanism via Ce3+/Ce4+redox pairs. The proposed ODH strategy by using oxygen vacancies enriched catalysts offers an important insight into the efficient dehydrogenation of ethylbenzene at mild conditions.Keywords:ethylbenzene;oxidative dehydrogenation;ceria;CO2
研究领域:
化学工程
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催化科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
·
IF 4.2
Siyuan Zhao,Ke Ma,Kailong He,Xiaoxun Ma,Chengyi Dai
Due to cost and energy consumption constraints, converting benzene into ethylbenzene using low-cost syngas instead of ethylene as an alkylation reagent is significant. However, when using syngas as the reaction raw material, generating ethylated side chains on the benzene ring is challenging. Instead, toluene/xylene becomes the primary product. We used a three-bed series connection method in a reactor, achieving one-step high selectivity of syngas and benzene to produce ethylbenzene. In the first bed layer (ZnAl2O4/SAPO-34), the syngas was first converted into methanol/dimethyl ether (DME) on ZnAl2O4. Then, it was further converted into low-carbon olefins on SAPO-34, with the microporous shape-selective effect of SAPO-34, inhibiting the generation of toluene/xylene in the alkylation of benzene with methanol/DME. At the same time, we proved that the absence of microporous shape-selective effect acid sites on the outer surface of S34 can lead to the occurrence of side reactions of benzene and methanol/DME methylation. In the second bed layer, SAPO-34 could continue to convert unconverted methanol/DME in the first bed layer into low-carbon olefins. In the third layer (ZSM-5), ethylene and benzene underwent highly selective alkylation on ZSM-5 to convert it into ethylbenzene. We found a “volcanic” curve relationship between the selectivity of ethylbenzene and the Brønsted acid site density of ZSM-5. On the one hand, Brønsted acid could catalyze the formation of ethylbenzene from benzene and ethylene; On the other hand, excessive Brønsted acid could lead to the isomerization of ethylbenzene to toluene/xylene. When the Brønsted acid showed a site density of 0.7 mmol/g, the selectivity of ethylbenzene was as high as 87%, with a byproduct of xylene showing only 0.3%, which is usually difficult to separate from ethylbenzene. Finally, the three-bed catalytic system showed no deactivation after 100 h.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
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IF 6.5
Fuping Song,Juping Zhang,Dongfang Li,Tao Zhu,Xing Zhu,Hua Wang
Oxidative dehydrogenation (ODH) of ethylbenzene is a promising process for styrene production. However, its application is limited by product overoxidation and purification requirements due to the co-feeding of mild oxidants. Herein, we report a facile manganese-based catalyst (K/Mn 3 O 4 -Al 2 O 3 ) and achieve competitive styrene selectivity of 88 % and ethylbenzene conversion of 95 % at 450 ℃ (84 % yield vs. ∼ 60 % yield in commercial dehydrogenation process at 600 ℃) under a cyclic redox ODH scheme. The introduction of Al 2 O 3 into MnO x restructures composite oxides and depresses bulk lattice-oxygen migration for the partial oxidation of ethylbenzene. The surface modification using potassium creates reactive sites and regulates surface properties, achieving ethylbenzene activation and high conversions. Highly active lattice oxygen in catalysts after bulk and surface modifications selectively converts ethylbenzene to styrene and water. This study provides an understanding of roles of manganese-based catalysts in styrene generation and offers a strategy to modulate lattice oxygen on catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2012
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IF 1.693
Baimei Yang,Hui Wan,Guofeng Guan
Isobaric vapor–liquid equilibrium (VLE) data are reported for binary mixtures of methyl formate + o-xylene, methyl formate + m-xylene, methyl formate + p-xylene, and methyl formate + ethylbenzene at 101.33 kPa. The data are obtained using a vapor recirculating type (modified Othmer's) equilibrium still. All of the binary systems show positive deviation from ideality. None of the systems form an azeotrope. The VLE data for these binary systems are checked to meet rigorous thermodynamic consistency by the Herington method and the point-to-point test of the Fredenslund method. The experimental VLE data are well-correlated by the nonrandom two-liquid (NRTL), universal quasichemical activity coefficient (UNIQUAC), and Wilson equations.
研究领域:
化学工程
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热力学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Xuewu Deng,Xiaobing Zheng,Feifei Jia,Cuiyao Cao,Haolei Song,Yanjun Jiang,Yunting Liu,Guanhua Liu,Shijie Li,Lihui Wang
The selective oxyfunctionalization of C-H and C C bonds is highly important and catalyzed by unspecific peroxygenases (UPOs) which suffer from inactivation by hydrogen peroxide (H 2 O 2 ). Herein, photo-enzyme integrated catalysts were constructed by immobilizing Aae UPO as cross-linked enzyme aggregates (CLEAs) in Pd-loaded three-dimensional ordered macroporous titania (3DOM TiO 2 ) with in situ photocatalytic H 2 O 2 production. The prepared Aae UPO@3DOM TiO 2 -Pd obtained higher catalytic efficiency compared with CLEAs- Aae UPO. The conversion of ethylbenzene to (R) -1-phenethyl alcohol was significantly improved, reaching 99 % compared with free enzyme (38 %) and CLEAs- Aae UPO (49 %), with ee value of > 99 %. Aae UPO@3DOM TiO 2 -Pd exhibited good stability and reusability attributed to the protection of macropores and in situ H 2 O 2 production. By using the designed 3DOM platform for photocatalysis and enzyme immobilization, the in situ photocatalytic generation of H 2 O 2 was highly efficient, and the monodisperse CLEAs- Aae UPO in the macropores facilitated the contact of substrate and enzyme, thus obtaining excellent photo-enzyme coupled catalysis.
研究领域:
生物化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
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2021
·Vol. 12
·期 2
·652-663
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IF 6.119
Chuanyu Yang,Zhongwen Dong,Weifeng Chu,Yanan Wang,Dongpu Zhao,Fucun Chen,Wenjie Xin,Xiangxue Zhu,Shenglin Liu,Longya Xu
A series of beta zeolite catalysts with controllable particle sizes and similar Si/Al ratios were prepared by introducing imidazole (IMD) into the synthesis system and used for liquid-phase transalkylation of diethylbenzene (DEB) with benzene (Bz). The beta zeolite catalyst prepared with an IMD/SiO2 molar ratio of 0.5 possessed the smallest particle size (mean particle size of 119 nm) and the highest DEB conversion of 79.16% under the reaction conditions: 260 °C, 4.0 MPa, WHSV (diethylbenzene) of 2.0 h−1, W(benzene)/W(diethylbenzene) of 3/1, time on stream of 5 h. Then, to elucidate the catalytic roles of acid sites with different strengths, types and positions in beta zeolite in the transalkylation reaction, we carried out Na+ loading on the prepared beta zeolite to eliminate strong acid sites and poisoned the Brønsted acid sites and external acid sites by using 2,4-dimethylquinoline (2,4-DMQ) and triphenylphosphorus (TPP) as toxic reagents, respectively. The results suggested that the moderate and strong Brønsted acid sites of beta-IMD0.5 were the active sites for the liquid-phase transalkylation of DEB with Bz and their utilization rate showed a trend of increasing first and then decreasing. Significantly, 31% of the external Brønsted acid sites of beta-IMD0.5 contributed 81% of DEB conversion. The external acid sites had more contribution to the reaction due to the short diffusion path and fine accessibility.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
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2025
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IF 4.7
Quanhua Wang,Yuhao Zong,Yanchao Liu,Haixia Hu,Yanwei Yue,Xingxing Xie,Lixing Guo,Qingyuan Hu,Hu Wang,Jinke Li,Jiajun Shi,Lichen Zhang,Jiajun Zheng,Shuwei Chen
The design and development of a highly efficient and stable catalyst for styrene (ST) obtained from ethylbenzene (EB) dehydrogenation reaction is urgently required because a commercial Fe–K-based catalyst often undergoes severe deactivation resulted from the active phase decomposition into inactive ferrite compound at high temperatures (>600 °C). Herein, ultra-fine Al 2 O 3 nanofibers which are further self-assembled to form uniform rod-like morphology (R–Al 2 O 3 ) were fabricated via a facile sol-gel strategy and further utilized as support to dispersing vanadium species (V/R–Al 2 O 3 ). The physicochemical properties of the samples were systematically characterized by XRD, Raman, SEM, TEM, H 2 -TPR, CO 2 -TPD, XPS, and 27 Al MAS NMR techniques. It is found that except that R–Al 2 O 3 support has the merits of a high specific surface area, lager pore volume, and uniform mesopore structure, the presence of the unsaturated pentacoordinate Al 3+ ions plays a pivotal role in better dispersing V active species, with the existence of the isolate and/or polymeric forms. As compared to V/C–Al 2 O 3 (commercial Al 2 O 3 as support), the V/R–Al 2 O 3 catalyst endows outperformed catalytic performances for oxidative dehydrogenation of ethylbenzene in the presence of CO 2 (OEBDH-CO 2 ). In which, the V/R–Al 2 O 3 catalyst gives a high EB catalytic activity and good stability without significant deactivation phenomenon being detected even after the third regeneration test. Such a result can be principally ascribed to that R–Al 2 O 3 support with excellent textural properties can better disperse V species so as to expose more active sites, which is beneficial for improving the conversion efficiency of EB. More importantly, keeping/regaining high valence state of V species in the V/R–Al 2 O 3 catalyst under CO 2 as a soft oxidant effectively promotes Mars-Van Krevelen redox cycle, further suppressing the catalyst deactivation. This work provides a rational design strategy for a high efficiency and stable dehydrogenation catalyst by optimizing the textural properties of Al 2 O 3 support and introducing the unsaturated pentacoordinate Al 3+ ions.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
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2024
·Vol. 14
·期 5
·288
·
IF 3.8
Tianyun Wang,Yingjie Guan,Haidan Wu,Zhaojie Su,Jianguo Zhuang,Siyan Yan,Xuedong Zhu,Fan Yang
Utilizing carbon dioxide as a carbon source for the synthesis of olefins and aromatics has emerged as one of the most practical methods for CO2reduction. In this study, an improved selectivity of 85% for targeting products (ethylbenzene and propylbenzene) is achieved with a benzene conversion of 16.8% by coupling the hydrogenation of carbon dioxide to olefins over the bifunctional catalyst “Oxide-Zeolite” (OX-ZEO) and the alkylation of benzene with olefins over ZSM-5. In addition to investigating the influence of SAPO-34 and ZSM-5 zeolite acidity on product distribution, catalyst deactivation due to coke formation is addressed by modifying both molecular sieves to be hierarchical to extend the catalyst lifespan. Even after 100 h of operation at 400 °C, the catalysts maintained over 80% selectivity towards the target products, with benzene conversion over 14.2%. Furthermore, the pathway of propylbenzene formation is demonstrated through simple experimental design, revealing that the surface Brønsted acid sites of SAPO-34 serve as its primary formation sites. This provides a novel perspective for further investigation of the reaction network.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
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IF 6.953
Kongyou Wu,Kungang Chai,Liqin Zhou,Zhiliang Duan,Haibo Wu,Zhenghui Huang,Dongli Li,Zhongwei Tan,Fang Shen,Zongwu Wei,Hongbing Ji
Herein, a TEMPO-oxidized cellulose-grafted-polystyrene hypercrosslinked polymer (TOC-PS-HCP) was synthesized facilely by TEMPO oxidation , grafting copolymerization and post crosslinking route. Based on the structural characterization, it was confirmed that TOC-PS-HCP mainly consisted of polystyrene chain on cellulose and rigid crosslinked bridge. Additionally, the as-prepared TOC-PS-HCP displayed appropriate hydrophobicity (water contact angle = 102.44°) and high specific surface area (S BET = 601.20 m 2 ·g ‐ −1 ), which could efficiently recover ethylbenzene and styrene from PO/SM wastewater. The adsorption experiment was conducted to study the recovery performance for ethylbenzene and styrene in the aqueous phase. The results showed that TOC-PS-HCP could recover ethylbenzene and styrene quickly by adsorption process, and maintain a stable recovery rate both in different aqueous conditions and recycle experiments. The adsorption experiment in the simulated wastewater solution showed that TOC-PS-HCP exhibited the greater affinity for ethylbenzene and styrene than other substrates. Furthermore, a possible mechanism for the efficient recovery of ethylbenzene and styrene was suggested on the basis of experimental and theoretical results, which may be associated with van der Waals force and π-π stacking.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2022
·Vol. 51
·期 10
·1247-1267
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IF 2
Yu Yingmin,Li Min,Liu Lanmu,Li Jun,Song Yuhe
In this paper, the separation of the p-xylene and ethylbenzene was explored. The COSMO-SAC-UNIFAC model, σ-profile analysis, solvent power and selectivity were used to screen for a suitable solvent for this process. Then, 1,2,4-trichlorobenzene was selected as target solvent to extract the p-xylene from ethylbenzene. The vapor–liquid-phase equilibrium (VLE) data for binary systems of p-xylene + ethylbenzene, p-xylene + 1,2,4-trichlorobenzene, and ethylbenzene + 1,2,4-trichlorobenzene and ternary system of p-xylene + ethylbenzene + 1,2,4-trichlorobenzene were determined with a modified Rose still at atmospheric pressure (101.3 kPa) and all the binary data passed the Wisniak’s test, which accorded with the thermodynamic consistency. Three thermodynamic models, Wilson, NRTL and UNIQUAC were used to correlate the VLE data and get binary interaction parameters, then the ternary VLE data of p-xylene + ethylbenzene + 1,2,4-trichlorobenzene were estimated based on these model parameters using Aspen Plus V10. The estimation values of the three models are in good agreement with the experimental data. Moreover, the effect of 1,2,4-trichlorobenzene was analyzed and it was found to be an effective candidate extractant for the extractive distillation of ethylbenzene from mixed xylenes.
研究领域:
化学工程
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热力学
✓ 已验证
DOI
高影响因子
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