Cumene is an important intermediate and chemical in chemical industry. In this work, directional preparation of cumene using lignin was achieved by a three-step cascade process. The mixture aromatics were first produc...Cumene is an important intermediate and chemical in chemical industry. In this work, directional preparation of cumene using lignin was achieved by a three-step cascade process. The mixture aromatics were first produced by the catalytic pyrolysis of lignin at 450 ℃ over I%Zn/HZSM-5 catalyst, monocyclic aromatics with the selectivity of 85.7 wt% were obtained. Then, the catalytic dealkylation matics with 93.6 wt% benzene at 600 ℃ of heavier aromatics resulted in benzene-rich aro- over Hβ catalyst. Finally, the cumene synthesis was performed by the aromatic alkylation, giving cumene selectivity of 91.6 C-tool% using the [bmim]Cl-2AlCl3 ionic liquid at room temperature for 15 min. Besides, adding a small amount of methanol to the feed can efficiently suppress the coke yield and enhance the aromatics yield. The proposed transformation potentially provides a useful route for production of cumene using renewable lignin.展开更多
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
In this work,a series of acidic montmorillonite/cordierite monolithic catalysts were prepared by a coating method using silica sol as the binder.The morphology and structure of the acidic montmorillonite/cordierite sa...In this work,a series of acidic montmorillonite/cordierite monolithic catalysts were prepared by a coating method using silica sol as the binder.The morphology and structure of the acidic montmorillonite/cordierite samples were characterized by means of X-ray diffraction(XRD),N_2 adsorption/desorption isotherms,and scanning electron microscope(SEM).The cleavage of cumene hydroperoxide(CHP) in a conventional fixed-bed reactor was chosen as a model reaction to evaluate the catalytic activity of the monolithic catalysts.The influences of acidic montmorillonite loading,reaction temperature.CHP concentration,and weight hourly space velocity(WHSV) on the catalytic activity and selectivity of phenol were studied.The results indicated that the obtained acidic montmorillonite/cordierite monolithic catalysts were firm and compact,and the loading of acidic montmorillonite was found to reach 40%(by mass) after three coating operations.The surface area of acidic montmorillonite/cordierite catalysts increases greatly as acidic montmorillonite loading increases due to higher surface area of acidic montmorillonite.Under the optimal reaction conditions(acidic montmorillonite loading of 32.5%(by mass),temperature of 80 ℃,a mass ratio of CHP to acetone of 1:3,and WHSV of CHP of 90 h^(-1)),the conversion of CHP can reach 100%,and the selectivity of phenol is up to 99.8%.展开更多
CuO nanoparticle was synthesized via wet chemical method and was characterized diffraction （XRD）, nitrogen adsorption-desorption, and scanning electron microscopy （SEM） by X-ray Catalytic oxidation of cumene with ...CuO nanoparticle was synthesized via wet chemical method and was characterized diffraction （XRD）, nitrogen adsorption-desorption, and scanning electron microscopy （SEM） by X-ray Catalytic oxidation of cumene with molecular oxygen was studied over CuO nanoparticle. The catalysts showed markedly higher activities as compared to CuO prepared by conventional method, CuO/Al2O3, or homogeneous copper catalyst under comparable reaction conditions. The cumene conversion, cumene hydroperoxide （CHP） yield, and selectivity using 0.25 g CuO nanoparticle catalyst and 0.1 mol cumene at 358 K for 7 h were 44.2%, 41.2% and 93.2%, respectively. The catalyst can be recycled. After 6 recycled experiments, no loss of catalytic activity was observed.展开更多
Two types of Mo containing metal-organic frameworks,denoted as Mo@COMOC-4 and PMA@MIL-101（Cr）,were synthesized respectively by a post-synthetic modification and a ship-in-bottle approach.The catalytic performance of...Two types of Mo containing metal-organic frameworks,denoted as Mo@COMOC-4 and PMA@MIL-101（Cr）,were synthesized respectively by a post-synthetic modification and a ship-in-bottle approach.The catalytic performance of both compounds in the epoxidation of propylene using cumene hydroperoxide（CHP） as oxidant was compared with MoO3@SiO2.A higher conversion（46.2%） and efficiency（87.4%） of CHP was observed for Mo@COMOC-4,whereas the heteropoly acids supported MIL-101 resulted in the decomposition of CHP due to its strong acidic character.Regenerability tests demonstrated that Mo@COMOC-4 could be reused for multiple runs without significant loss in both activity and stability.展开更多
In 2019 the 150 kt/a unit for production of propylene oxide(PO)by the cumene hydroperoxide(CHP)process,the development of which is led by the SINOPEC Shanghai Research Institute of Petrochemical Technology(SRIPT),has ...In 2019 the 150 kt/a unit for production of propylene oxide(PO)by the cumene hydroperoxide(CHP)process,the development of which is led by the SINOPEC Shanghai Research Institute of Petrochemical Technology(SRIPT),has been envisaged in SINOPEC’s“Ten Key Technological Research Projects”to usher in a new phase for the R&D of this project.展开更多
This paper discusses robust control strategy for isopropyl benzene production process using the method of loop shaping H_(∞) technology.This cumene production process is a part of phenol plant in HOCL,Kochi.H_(∞) co...This paper discusses robust control strategy for isopropyl benzene production process using the method of loop shaping H_(∞) technology.This cumene production process is a part of phenol plant in HOCL,Kochi.H_(∞) control of the propylene concentration is done here.The H_(∞) controller is derived from the linearised model of the reactor.The optimal H_(∞) controller is obtained by simplifying two algebraic Riccati equations.The proposed PID-like H_(∞) controller provides a single tuning parameter which makes the controller design more accurate.The proposed controller has been compared with other robust controllers like H_(2) and LQR.The H_(∞) controller is found to be superior in a wide frequency range and has a feature of low distortion and good regulating performance.The reactor model has been developed in COMSOL Multiphysics with the parameters obtained from HOCL plant,Kochi.The model extracted is reduced using model order reduction for the controller design.展开更多
1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homog...1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homogeneous systems.The polymer-supported catalysts enhance their thermal stability,selectivity,recyclability and easy separation from reaction products leading to the operationally flexible[1-2].Such behaviour prompted us to know the effect of pore structures of polymer supporters on catalytic ...展开更多
文摘Cumene is an important intermediate and chemical in chemical industry. In this work, directional preparation of cumene using lignin was achieved by a three-step cascade process. The mixture aromatics were first produced by the catalytic pyrolysis of lignin at 450 ℃ over I%Zn/HZSM-5 catalyst, monocyclic aromatics with the selectivity of 85.7 wt% were obtained. Then, the catalytic dealkylation matics with 93.6 wt% benzene at 600 ℃ of heavier aromatics resulted in benzene-rich aro- over Hβ catalyst. Finally, the cumene synthesis was performed by the aromatic alkylation, giving cumene selectivity of 91.6 C-tool% using the [bmim]Cl-2AlCl3 ionic liquid at room temperature for 15 min. Besides, adding a small amount of methanol to the feed can efficiently suppress the coke yield and enhance the aromatics yield. The proposed transformation potentially provides a useful route for production of cumene using renewable lignin.
基金Supports by the National Key Research and Development Plan(2016YFB0301503)the Jiangsu Natural Science Foundation for Distinguished Young Scholars(BK20150044)+3 种基金the National Natural Science Foundation of China(91534110,21606124)the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(14KJB530004)the Foundation from State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201402,ZK201407)the Technology Innovation Foundation for Science and Technology Enterprises in Jiangsu Province(BC2015008)
文摘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.
基金Supported by the National Natural Science Foundation of China(21121064,21076008,21206008)the Projects in the National Science&Technology Pillar Program during the 12th Five-Year Plan Period(2011BAC06B04)the Research Fund for the Doctoral Program of Higher Education of China(20120010110002)
文摘In this work,a series of acidic montmorillonite/cordierite monolithic catalysts were prepared by a coating method using silica sol as the binder.The morphology and structure of the acidic montmorillonite/cordierite samples were characterized by means of X-ray diffraction(XRD),N_2 adsorption/desorption isotherms,and scanning electron microscope(SEM).The cleavage of cumene hydroperoxide(CHP) in a conventional fixed-bed reactor was chosen as a model reaction to evaluate the catalytic activity of the monolithic catalysts.The influences of acidic montmorillonite loading,reaction temperature.CHP concentration,and weight hourly space velocity(WHSV) on the catalytic activity and selectivity of phenol were studied.The results indicated that the obtained acidic montmorillonite/cordierite monolithic catalysts were firm and compact,and the loading of acidic montmorillonite was found to reach 40%(by mass) after three coating operations.The surface area of acidic montmorillonite/cordierite catalysts increases greatly as acidic montmorillonite loading increases due to higher surface area of acidic montmorillonite.Under the optimal reaction conditions(acidic montmorillonite loading of 32.5%(by mass),temperature of 80 ℃,a mass ratio of CHP to acetone of 1:3,and WHSV of CHP of 90 h^(-1)),the conversion of CHP can reach 100%,and the selectivity of phenol is up to 99.8%.
基金This work is supported by the Natural Science Foundation of South China University of China(143E5041280)
文摘CuO nanoparticle was synthesized via wet chemical method and was characterized diffraction （XRD）, nitrogen adsorption-desorption, and scanning electron microscopy （SEM） by X-ray Catalytic oxidation of cumene with molecular oxygen was studied over CuO nanoparticle. The catalysts showed markedly higher activities as compared to CuO prepared by conventional method, CuO/Al2O3, or homogeneous copper catalyst under comparable reaction conditions. The cumene conversion, cumene hydroperoxide （CHP） yield, and selectivity using 0.25 g CuO nanoparticle catalyst and 0.1 mol cumene at 358 K for 7 h were 44.2%, 41.2% and 93.2%, respectively. The catalyst can be recycled. After 6 recycled experiments, no loss of catalytic activity was observed.
基金financially supported by National Natural Science Foundation of China(No.21403025)Scientific Research Foundation for Returned Scholars,Ministry of Education of China+1 种基金the State Key Laboratory of Fine Chemicals(No.KF1405)support from the Ghent University BOF-post-doctoral Grant 01P06813T
文摘Two types of Mo containing metal-organic frameworks,denoted as Mo@COMOC-4 and PMA@MIL-101（Cr）,were synthesized respectively by a post-synthetic modification and a ship-in-bottle approach.The catalytic performance of both compounds in the epoxidation of propylene using cumene hydroperoxide（CHP） as oxidant was compared with MoO3@SiO2.A higher conversion（46.2%） and efficiency（87.4%） of CHP was observed for Mo@COMOC-4,whereas the heteropoly acids supported MIL-101 resulted in the decomposition of CHP due to its strong acidic character.Regenerability tests demonstrated that Mo@COMOC-4 could be reused for multiple runs without significant loss in both activity and stability.
文摘In 2019 the 150 kt/a unit for production of propylene oxide(PO)by the cumene hydroperoxide(CHP)process,the development of which is led by the SINOPEC Shanghai Research Institute of Petrochemical Technology(SRIPT),has been envisaged in SINOPEC’s“Ten Key Technological Research Projects”to usher in a new phase for the R&D of this project.
文摘This paper discusses robust control strategy for isopropyl benzene production process using the method of loop shaping H_(∞) technology.This cumene production process is a part of phenol plant in HOCL,Kochi.H_(∞) control of the propylene concentration is done here.The H_(∞) controller is derived from the linearised model of the reactor.The optimal H_(∞) controller is obtained by simplifying two algebraic Riccati equations.The proposed PID-like H_(∞) controller provides a single tuning parameter which makes the controller design more accurate.The proposed controller has been compared with other robust controllers like H_(2) and LQR.The H_(∞) controller is found to be superior in a wide frequency range and has a feature of low distortion and good regulating performance.The reactor model has been developed in COMSOL Multiphysics with the parameters obtained from HOCL plant,Kochi.The model extracted is reduced using model order reduction for the controller design.
文摘1 Introduction Immobilization of homogeneous catalysts onto polymer supports through covalent attachment has received wide attention because these materials offer advantage features of heterogeneous catalysis to homogeneous systems.The polymer-supported catalysts enhance their thermal stability,selectivity,recyclability and easy separation from reaction products leading to the operationally flexible[1-2].Such behaviour prompted us to know the effect of pore structures of polymer supporters on catalytic ...
