JOURNAL OF CHEMICAL THERMODYNAMICS
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2020
·
IF 2.888
Chunhao Guo,Yang Tang,Jinru Wan,Yue Zuo,Yong Wang,Yichang Wang,Xunqiu Wang
The isobaric vapour–liquid equilibrium (VLE) data for the binary system of cyclohexanol + cyclohexylbenzene were determined at (5, 10, 15, 20 and 25) kPa with a dynamic recirculating apparatus and the temperature ranged from 358.10 K to 456.43 K, and the thermodynamic consistency of the experimental data was checked by the Herington area method and Van Ness method. Afterwards, the experimental data was correlated with NRTL, Wilson and UNIQUAC model, and the corresponding interaction of thermodynamic models of the binary system parameters were obtained through the Aspen software. The results indicated that all three models represent the experimental values quite well, while the NRTL model provided a slightly better result than Wilson model and UNIQUAC model. The maximum root mean square deviation of the temperature and vapour phase mole fraction for the NRTL model was less than 0.4 K and 0.004, respectively.
研究领域:
化学工程
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热力学
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 153
·期 5
·1300-1307
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IF 2.936
Zhu Guozhi,Shi Song,Feng Xiao,Zhao Li,Cao Jieqi,Wang Yinwei,Sun Zhiqiang,Gao Jin,Xu Jie
Selective oxidation of cyclohexylbenzene is a potentially promising process in industrial application. Herein, we reported an organocatalytic system to achieve the selective oxidation of C α –H bonds in cyclohexylbenzene and transformation of active intermediate C α peroxide by an oxidation then decomposition method. The pair of N -hydroxyphthalimide and 2-Chlorothraquinone (NHPI/AQ-Cl) as metal-free organic catalysts showed the highest efficient in selective oxidation of cyclohexylbenzene to C α peroxide and C α alcohol. And the base modified covalent triazine frameworks could facilitate the C α peroxide decomposition to the C α alcohol. Up to 8.8% conversion of substrate and 80% selectivity of 1-phenylcyoclohexanol were achieved under the optimized conditions. This work provided a new organocatalytic strategy to achieve the aerobic selective oxidation of C α –H bonds in cyclohexylbenzene. Graphical Abstract
研究领域:
化学
·
工业化学
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产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2020
·
IF 5.825
Genkuo Nie,Yiying Dai,Junjian Xie,Xiangwen Zhang,Lun Pan,Ji-Jun Zou
Fuel blending generally exhibits better low-temperature flow properties (i.e. low viscosity, low freezing point) than pure component fuel. Here, a fuel bending containing bicyclohexane and (cyclopentylmethyl)cyclohexane was synthesized directly by hydroisomerization of cyclohexylphenol to reduce the freezing point. The selectivity of (cyclopentylmethyl)cyclohexane formed by isomerization is enhanced through inhibiting the quick hydrogenation of intermediates using mixing acid catalyst and metal catalyst. Zeolite with strong Brønsted acid site and big surface area, such as HZSM-5 is better for the isomerization. Catalyzed by mixture of Pd/C and HZSM-5, the obtained fuel blending improves the freezing point from 2.6 °C to−22 °C compared with pure bicyclohexane, meanwhile keep the high density of 0.880 g/mL unchanged. The improved low-temperature property is contributed to the formation of (cyclopentylmethyl)cyclohexane. Moreover, the pathways of isomerization and its competition with hydrodeoxygenation are also investigated.
研究领域:
化学工程
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能源科学
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产品关联
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
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2024
·
IF 2.5
Xue Changhao,Hou Xiaohui,Sun Weijie,Yuan Xia
The acidic molecular sieve carrier Hβ supported non-noble metal catalyst Ni/Hβ was prepared by equal volume impregnation method and applied to the hydroalkylation of benzene to cyclohexylbenzene. The effects of calcination procedures on the particle size of Ni and the dispersion degree of metal on the carrier were investigated. Compared with the samples reduced by hydrogen after calcination, the active site Ni of Ni/Hβ obtained by direct thermal reduction in hydrogen is mainly dispersed on the surface of the carrier, with better metal dispersion and smaller particle size of Ni. Under the optimized reaction conditions, the initial pressure of H 2 is 2.5 MPa, the amount of catalyst is 4% of the total reaction liquid, and at the reaction temperature 190 °C for 3 h, the conversion of benzene is 38.4%, the selectivity of cyclohexylbenzene is 72.8%, the selectivity of cyclohexane is 5.2%, the selectivity of dicyclohexylbenzene is 16.5%, and the selectivity of other by-products decreased to 5.5%. After the catalyst was reused for 5 times, the conversion of benzene and selectivity of cyclohexylbenzene were both have a slight decrease. Characterization results showed that the structure of the recovered catalyst was stable, but the specific surface area and pore volume decreased significantly, the resulted problem of catalyst pore blockage can be restored through calcination treatment.
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
高影响因子
Catalysts
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2024
·Vol. 14
·期 10
·727
·
IF 3.8
Jie Fan,Wei Li,Jingyi Yang,Tao Yang,Zhongyi Liu,Meng Zhang
With the rapid development of modern society, the consumption of fossil fuels during the industrial production process produces a significant amount of carcinogens. Converting the highly toxic biphenyl (BP) to the valuable product cyclohexylbenzene (CHB) can decrease the emission of carcinogenic aromatic hydrocarbons. In this study, we prepared a series of 20%Ni/SiO2catalysts with different specific surface areas (SSAs) using the over-volume impregnation method, as well as 20%M/SiO2(M = Fe, Cu, Co, and Ni) catalysts to highlight the effects of support SSAs and active metal on the performance of BP selective hydrogenation to CHB. The catalysts were characterized by XRD, N2physisorption, TEM, and H2-TPR, which demonstrated that a high SSA would be helpful for the dispersion of the active metal. The evaluation results revealed that 20%Ni/SiO2-300 exhibited excellent activity and stability in the selective hydrogenation of BP to CHB (BP conversion: 99.6%, CHB yield: 99.3% at the conditions of 200 °C, 3 MPa, 4 h and isopropanol as the solvent) among the catalysts with different SSAs, which was also superior to the performance over the catalysts with other transition metals as the active sites. The structure–activity relationship of the employed catalysts for the selective hydrogenation of BP to CHB was also discussed.
研究领域:
催化化学
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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
INTERNATIONAL JOURNAL OF CHEMICAL KINETICS
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2021
·Vol. 54
·期 2
·71-80
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IF 1.462
Yufei Yang,Yadong Zhang
In this work, a HPW/ZSM-5 catalyst was prepared by impregnating phosphotungstic acid (HPW) with carrier ZSM-5 zeolite and characterized by XRD, SEM, N 2 adsorption/desorption isotherm, NH 3 -TPD, and FT-IR techniques. The catalytic performance of HPW/ZSM-5 was investigated by using the decomposition reaction of cyclohexylbenzene-1-hydroperoxide (CHBHP) to phenol and cyclohexanone. The conversion rate of CHBHP was up to 97.28%. In addition, the reusability test exhibited that the high durability HPW/ZSM-5 as the conversion rate of CHBHP only decreased by 3.11% after five runs. The kinetic study of the decomposition reaction indicated it was a primary reaction. The apparent activation energy of the decomposition reaction was 102.39 kJ·mol –1 in the temperature range of 45–60℃. All results indicate that the HPW/ZSM-5 catalyst has good performance and promising applications in acid catalyzed organic chemistry.
研究领域:
催化化学
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有机化学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Jiawei Yang,Feifei Wang,Chaobo Liang,Shaofeng Zhou,Jin Huang,Guizhe Zhao,Yaqing Liu
Natural rubber (NR) and butadiene rubber (BR) composites are frequently used in manufacturing tires and conveyor belts, which are susceptible to severe wear, leading to product failure and significant losses. To enhance the wear resistance of NR/BR composites, we prepared NR/BR composites reinforced with a synergy of N-cyclohexylbenzothiazole-2-sulfonamide surface one-step modified reduced graphene oxide (CZ-rGO) and carbon black N234 (CB) using a latex co-precipitation method. This study explored the effects of GO content and CZ modification on the structure, wear resistance, thermal conductivity, and mechanical properties of the NR/BR blended composites. It showed that adding 2 phr of GO resulted in excellent filler dispersion, significantly improving the tensile strength, elongation at break, tear strength, thermal conductivity, and wear resistance of the composites. The incorporation of CZ-rGO further increased the crosslinking density, vulcanization performance, and filler dispersion with enhanced mechanical properties, thermal conductivity, and wear resistance of the composites. Notably, the DIN abrasion volume was reduced to 77.88 mm³, surpassing the ISO 10247 standard for conveyor belt cover rubber in terms of wear resistance. The wear resistance of NR/BR/CZ-rGO composites is not only significantly higher than that of single NR- or SBR-based rubber composites, but also significantly higher than that of other binary rubber blend composites, and the CZ-rGO filler is simpler in composition and structure and exhibits a more prominent wear enhancement. This work provides guidance for an efficient and environmentally friendly approach to GO surface modification, as well as useful insights for the development of high wear-resistant rubber composites with excellent overall performance.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
Journal of Sulfur Chemistry
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2020
·
IF 1.963
Lin Yan,Jun Yang,Xu-Feng Liu,Yu-Long Li,Xing-Hai Liu,Zhong-Qing Jiang
In this article, two new binuclear iron compounds [Fe2(CO)5PPh(C6H11)2{µ-SCH2CH(CH2CH3)S}] (2) and [Fe2(CO)5PPh2(C6H11){µ-SCH2CH(CH2CH3)S}] (3), which can be regarded as the biomimics for the active site of [FeFe]-H2ases, have been synthesized by CO exchange of compound [Fe2(CO)6{μ-SCH2CH(CH2CH3)S}] (1) with cyclohexyldiph-enylphosphine or dicyclohexylphenylphosphine and their structures have been confirmed by spectroscopy, elemental analysis, and X-ray crystallography. They also exhibited good electrocatalytic activities for the generation of H2.
研究领域:
无机化学
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材料科学
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生物无机化学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
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2020
·Vol. 10
·期 5
·1467-1476
·
IF 5.721
Zhuo-Qian Li,Xinxin Fu,Caiyan Gao,Jinyu Huang,Baojun Li,Yongpeng Yang,Jie Gao,Yonglong Shen,Zhikun Peng,Jing-He Yang,Zhongyi Liu
The one-step hydroalkylation of benzene to cyclohexylbenzene (CHB) needs to occur on bifunctional metal/zeolite catalysts, and introducing more acid sites to match the metal sites plays a key role in improving the matching of acid/metal sites toward the requirements of benzene hydroalkylation. Herein, we designed and constructed a Si–Al framework coating with extra acid sites outside the surface of the Pd/HBeta catalyst and obtained a zeolite-encaged Pd NP structure (Pd@HBeta). Notably, the Pd@HBeta catalysts achieved excellent catalytic performance with 44.0% CHB selectivity at about 85.0% benzene conversion, which is much higher than that of the Pd/HBeta catalyst with a CHB selectivity of 25.1% at the same benzene conversion. The remarkable increment of CHB selectivity of Pd@HBeta is mainly attributed to the extra acid sites provided by the coated Si–Al framework as well as the increase of the B/L ratio. Moreover, the adsorption capacity of benzene and cyclohexene is greatly improved after introducing extra acid sites by coating the Si–Al framework, which is beneficial for both hydrogenation and alkylation. Further DFT calculations reveal that C6H10 can easily desorb from Pd NPs and migrate to the acidic channel of HBeta in the Pd@HBeta catalyst than that in Pd/HBeta. Our work presents an elegant example of catalytic hydroalkylation selectivity regulation by coating an extra Si–Al framework to enhance the matching of acid/metal balance.
研究领域:
催化
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化学工程
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材料科学
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物理化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
·
IF 9
Wei Chen,Yan Ding,Fang Wang,Zhixia Xu,Qing Ye,Jinlong Li,Patrice Paricaud
The vapor-liquid equilibria of binary mixtures of ethylene glycol diacetate (EGDA) + o-chlorotoluene (OCT) and EGDA + cyclohexylbenzene (CHB), and the liquid-liquid equilibria (LLE) in ternary mixtures of ethylene glycol (EG) + EGDA + o-chlorotoluene and EG + EGDA + cyclohexylbenzene are measured in this work. The new data have been described with the NRTL thermodynamic model. The heterogeneous extractive distillation and liquid-liquid phase separation process for the investigated systems are then simulated using the Aspen Plus software and the adjusted thermodynamic model. The influence of key process parameters such as the ratio of solvent flow rate to feed flowrate, the plate number and the reflux ratio on the separation process are analyzed in detail, and the optimal process parameters are determined. An economic and environmental study of the process is then performed. It is found that the two extractants (o-chlorotoluene and cyclohexylbenzene) can achieve a good EG + EGDA azeotrope separation. The purities of both EG and EGDA products are greater than 99.50 wt% in the two processes. The predicted selectivity obtained with o-chlorotoluene is higher than the one obtained with cyclohexylbenzene process. However, the cyclohexylbenzene process is found to be was more environmentally friendly, and the utility costs and CO 2 emissions of are lower. This work brings new insights in the design and optimization for the separation of EG and EGDA azeotropic mixtures.
研究领域:
化学工程
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过程系统工程
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热力学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
Results in Engineering
·
2023
·
IF 5
Yeqing Huang,Manna Wang,Yi Huang,Jin Shang,Baoyu Liu
The distribution of Brønsted acid sites in three-dimensional 12-membered pore channels of Beta zeolite was a decisive factor in the alkylation of benzene with cyclohexene. Here, the Brønsted acid site distribution in Beta zeolitic channels was precisely regulated by tuning the content of Na + in crystallization system combined with tetraethylammonium cation, the Beta-55 with Brønsted acid sites exclusively located in straight channels (along a - and b -axis directions) was successfully synthesized by utilizing tetraethylammonium as the structure-directing agents without Na + species, and the fraction of Brønsted acid sites in sinusoidal/straight channels of Beta zeolites can be accurately controlled by tailoring the content of Na + in synthesis gel. Catalytic properties in the liquid alkylation between benzene and cyclohexene exhibited that Beta-55 zeolites with the Brønsted acid sites solely located in a -axis and b -axis channels showed the highest cyclohexene conversion, cyclohexylbenzene selectivity and longest lifetime in this reaction. In addition, the resultant Beta zeolites also exhibited low coke generation rate and robust regeneration performance in the alkylation reaction.
研究领域:
催化
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化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
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2025
·
IF 8.9
Xiyang Su,Weixi Gao,Sepideh Sadat Hosseini Noorabadi,Yihao Li,Patrick Ryan Galligan,Yapeng Chen,Xingyi Zhang,Jinglei Yang
As an emerging low-energy-consumption and rapid-processing technique, frontal polymerization (FP) has garnered increasing attention due to its significant potential in free-standing three-dimensional printing, advanced composite manufacturing etc. However, effects from thermal expansion, chemical shrinkage, and nonuniform reaction propagation during the FP process inevitably generate gradient deformations at the FP front, adversely affecting the mechanical properties of the final processed components. To elucidate the intrinsic deformation mechanisms of polymer materials during FP and optimize their mechanical performance after polymerization, we employ a representative dicyclopentadiene (DCPD) gel system for investigation. In this study, simultaneous temperature and strain measurement revealed anisotropic deformation patterns of DCPD gels during FP. Meanwhile, experimental and numerical studies investigated the strain evolution of DCPD gels during both single and multi-point initiation of FP, revealing that the maximum compressive strain in uncured regions gradually decreased with increasing pre-curing degree but increased with rising width. Finally, mechanical characterization results show that, as the pre-curing degree increases, both compressive and tensile performances of polydicyclopentadiene are progressively enhanced, with yield strengths under tension and compression at 77 K significantly exceeding those at room temperature. These findings provide an experimental and theoretical foundation for high-performance material fabrication based on FP of gel-state systems.
研究领域:
高分子科学
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材料工程
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热加工
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增材制造
·
智能材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）