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
Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H+ and the route of reaction initi...Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H+ and the route of reaction initiated the alkylation of benzene with ethylene catalyzed by [bmim]Cl/FeCl3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity for the alkylation of benzene with ethylene suggests that there exists a new catalytic route. The distinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of [bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shifts of proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl3 content and shifted downfield when FeCl3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to be disengaged from imidazolium ring with formation of H+ to initiate the reaction. The isotope-substituted method was employed to prove this mechanism, through the GC-MS analysis of alkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeCl3 ionic liquid was found to follow the carbocation mechanism, the resource of H+ was presented and proved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found that the intensity of 2-H reduced 23% after reaction showing that the H+ arising from alkylation reaction was supplied by 2-H on the imidazole ring.展开更多
The surface intermediate (C_2H_5^+ and CH_3C_6H_5^+) and the reactive pathway of nuclear alkylation of toluene with ethylene to para—ethyl toluene over Mg salt and phosphorus acid modified ZSM—5 zeolites have been s...The surface intermediate (C_2H_5^+ and CH_3C_6H_5^+) and the reactive pathway of nuclear alkylation of toluene with ethylene to para—ethyl toluene over Mg salt and phosphorus acid modified ZSM—5 zeolites have been studied by 1R and EPR methods.展开更多
Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of toluene.We have prepared ten new nickel(Ⅱ)dibromide complexes w...Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of toluene.We have prepared ten new nickel(Ⅱ)dibromide complexes with various substituted bis(azolyl)methanes.They have been characterized using^(1)H NMR,IR,high resolution mass spectrometry and elemental analysis.The structures of three complexes have been unambiguously established using X-ray diffraction.It was found that these complexes in the presence of Et2AlCl or Et_(3)Al_(2)Cl_(3)are active both in ethylene oligomerization and Friedel-Crafts alkylation processes(activity up to 3720 kgoligomer·mol[Ni]^(−1)·h^(−1)).The use of Et_(3)Al_(2)Cl_(3)results in a higher share of alkylated products(up to 60%).Moreover,catalytic systems activated with Et_(3)Al_(2)Cl_(3)produced small amounts of odd carbon number olefins(up to 0.8%).The Friedel-Crafts alkylation was used as a trap for previously undetected short-chain odd carbon number olefins(C_(3)and C_(5)).展开更多
The study of the interaction of three glycol ethers, i.e. 2-methoxyethanol (ME), 2-ethoxyethanol (EE) and 2-butoxyethanol (BE) administered subcutaneously for 4 weeks and ethanol simultaneously given as 10% w/v soluti...The study of the interaction of three glycol ethers, i.e. 2-methoxyethanol (ME), 2-ethoxyethanol (EE) and 2-butoxyethanol (BE) administered subcutaneously for 4 weeks and ethanol simultaneously given as 10% w/v solution for drinking in male rats, was carried out from a toxicodynamic point of view. Administered alone, ME (2.5 and 5.0 mM/kg), EE (2.5 and 5.0 mM/kg) or BE (0.75 and 1.25 mM/kg) resulted in a decrease of red blood cells (RBC), packed cell volumes (PCV), and hemoglobin concentration (HGB), as well as an increase in mean corpuscular volume (MCV) and reticulocyte count (Ret). In the rats co-ex- posed to ethanol and EGAEs, a significantly less pronounced hematological changes in comparison with animal exposed to these ethers alone were seen. The rats simultaneously exposed to ethanol and both ME and EE at the lower dose demonstrated mainly protection from the alterations in leukocyte system. In contrast, in the rats which consumed ethanol and were simultaneously treated with the higher dose of ME or EE (5.0 mM/kg) the amelioration of same hematological parameters were displayed. The intake of ethanol along with BE treatment at both doses resulted in markedly ameliorated hematological parameters, compared to those which were changed by BE alone. In conclusion, the decrease of the hemolytic effects of EGAEs is ethanol dependent. Ethanol is a substrate of alcohol dehydrogenase (ADH), and affinity of this enzyme to ethanol is greater than that to glycol ethers. It is possible that ethanol results in the change in EGAEs metabolism.展开更多
采用晶种导向的方法,在不同晶化温度(80~170℃)下水热合成了b轴厚度为50 nm的ZSM-5分子筛;采用XRD、SEM、NH_(3)-TPD、Py-IR、XPS、ICP-AES、^(27)Al MAS NMR和UV-vis-DRS等手段对ZSM-5分子筛进行表征,研究了晶化温度对ZSM-5分子筛晶体...采用晶种导向的方法,在不同晶化温度(80~170℃)下水热合成了b轴厚度为50 nm的ZSM-5分子筛;采用XRD、SEM、NH_(3)-TPD、Py-IR、XPS、ICP-AES、^(27)Al MAS NMR和UV-vis-DRS等手段对ZSM-5分子筛进行表征,研究了晶化温度对ZSM-5分子筛晶体生长和铝分布的影响,并考察了不同晶化温度制备的ZSM-5分子筛催化剂在苯-稀乙烯烷基化反应中的催化性能。结果表明:晶化温度改变了ZSM-5分子筛的铝分布,从而影响分子筛的酸性质和烷基化反应性能;低晶化温度80℃下制备的ZSM-5分子筛具有酸性弱,总酸量少、Lewis酸以及外表面酸中心少,骨架铝(Al_(F))主要分布在直孔道和交叉孔道处;在反应温度360℃、压力1.4 MPa、苯/稀乙烯摩尔比1、稀乙烯质量空速1.5 h^(-1)、反应时间35 h的条件下,H-ZSM-5-80分子筛催化苯-稀乙烯烷基化反应,乙基选择性最高为95.4%,副产物二甲苯选择性最低为0.09%。展开更多
The MCM 49 zeolite was successfully synthesized using an organic mixture solution (OMS) yielded from hydrogenation of caprolactam as the template instead of the pure hexamethyleneimine (HMI). The OMS contains HMI (76...The MCM 49 zeolite was successfully synthesized using an organic mixture solution (OMS) yielded from hydrogenation of caprolactam as the template instead of the pure hexamethyleneimine (HMI). The OMS contains HMI (76 0%～84 0%), caprolactam (1 0%～10 0%), water, and a few by products. So the synthesis cost of the MCM 49 zeolite decreases obviously. The MCM 49 zeolite synthesized using OMS as the template shows similar crystallinity and purity to that synthesized using pure HMI in conventional process. From the results of NH 3 TPD, N 2 adsorption isotherm, and DTA, it is evident that the MCM 49 zeolite possesses three kinds of acidic centers with different strength, and has a high specific surface area and good thermostability. Furthermore, the MCM 49 zeolite shows good catalytic behavior for the alkylation of benzene with dilute ethylene to ethylbenzene.展开更多
基金This work is supported by the National 973 Project of China (2009CB623501)
文摘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.
文摘Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H+ and the route of reaction initiated the alkylation of benzene with ethylene catalyzed by [bmim]Cl/FeCl3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity for the alkylation of benzene with ethylene suggests that there exists a new catalytic route. The distinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of [bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shifts of proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl3 content and shifted downfield when FeCl3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to be disengaged from imidazolium ring with formation of H+ to initiate the reaction. The isotope-substituted method was employed to prove this mechanism, through the GC-MS analysis of alkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeCl3 ionic liquid was found to follow the carbocation mechanism, the resource of H+ was presented and proved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found that the intensity of 2-H reduced 23% after reaction showing that the H+ arising from alkylation reaction was supplied by 2-H on the imidazole ring.
文摘The surface intermediate (C_2H_5^+ and CH_3C_6H_5^+) and the reactive pathway of nuclear alkylation of toluene with ethylene to para—ethyl toluene over Mg salt and phosphorus acid modified ZSM—5 zeolites have been studied by 1R and EPR methods.
基金This work was financially supported by the Russian Science Foundation-Russia(Project No.22-23-00578)NMR measurement was performed according to the Development Program of the Interdisciplinary Scientific and Educational School of Lomonosov Moscow State University"The future of the planet and global environmental change"'X-Ray analysis was supported by the RUDN University Strategic Academic Leadership Program.Elemental and GC analyses were performed with the financial support from the Ministry of Science and Higher Education of the Russian Federation using the equipment of the Centre for molecularcomposition studies of INEOS RAS.
文摘Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of toluene.We have prepared ten new nickel(Ⅱ)dibromide complexes with various substituted bis(azolyl)methanes.They have been characterized using^(1)H NMR,IR,high resolution mass spectrometry and elemental analysis.The structures of three complexes have been unambiguously established using X-ray diffraction.It was found that these complexes in the presence of Et2AlCl or Et_(3)Al_(2)Cl_(3)are active both in ethylene oligomerization and Friedel-Crafts alkylation processes(activity up to 3720 kgoligomer·mol[Ni]^(−1)·h^(−1)).The use of Et_(3)Al_(2)Cl_(3)results in a higher share of alkylated products(up to 60%).Moreover,catalytic systems activated with Et_(3)Al_(2)Cl_(3)produced small amounts of odd carbon number olefins(up to 0.8%).The Friedel-Crafts alkylation was used as a trap for previously undetected short-chain odd carbon number olefins(C_(3)and C_(5)).
文摘The study of the interaction of three glycol ethers, i.e. 2-methoxyethanol (ME), 2-ethoxyethanol (EE) and 2-butoxyethanol (BE) administered subcutaneously for 4 weeks and ethanol simultaneously given as 10% w/v solution for drinking in male rats, was carried out from a toxicodynamic point of view. Administered alone, ME (2.5 and 5.0 mM/kg), EE (2.5 and 5.0 mM/kg) or BE (0.75 and 1.25 mM/kg) resulted in a decrease of red blood cells (RBC), packed cell volumes (PCV), and hemoglobin concentration (HGB), as well as an increase in mean corpuscular volume (MCV) and reticulocyte count (Ret). In the rats co-ex- posed to ethanol and EGAEs, a significantly less pronounced hematological changes in comparison with animal exposed to these ethers alone were seen. The rats simultaneously exposed to ethanol and both ME and EE at the lower dose demonstrated mainly protection from the alterations in leukocyte system. In contrast, in the rats which consumed ethanol and were simultaneously treated with the higher dose of ME or EE (5.0 mM/kg) the amelioration of same hematological parameters were displayed. The intake of ethanol along with BE treatment at both doses resulted in markedly ameliorated hematological parameters, compared to those which were changed by BE alone. In conclusion, the decrease of the hemolytic effects of EGAEs is ethanol dependent. Ethanol is a substrate of alcohol dehydrogenase (ADH), and affinity of this enzyme to ethanol is greater than that to glycol ethers. It is possible that ethanol results in the change in EGAEs metabolism.
文摘The MCM 49 zeolite was successfully synthesized using an organic mixture solution (OMS) yielded from hydrogenation of caprolactam as the template instead of the pure hexamethyleneimine (HMI). The OMS contains HMI (76 0%～84 0%), caprolactam (1 0%～10 0%), water, and a few by products. So the synthesis cost of the MCM 49 zeolite decreases obviously. The MCM 49 zeolite synthesized using OMS as the template shows similar crystallinity and purity to that synthesized using pure HMI in conventional process. From the results of NH 3 TPD, N 2 adsorption isotherm, and DTA, it is evident that the MCM 49 zeolite possesses three kinds of acidic centers with different strength, and has a high specific surface area and good thermostability. Furthermore, the MCM 49 zeolite shows good catalytic behavior for the alkylation of benzene with dilute ethylene to ethylbenzene.
