Song J.,Henan University of Urban Construction |
Li C.,Henan University of Urban Construction |
Zhao T.,Ministry Province Co cultivated State Key Laboratory Base of Natural GasConversion |
Ma Q.,Ministry Province Co cultivated State Key Laboratory Base of Natural GasConversion
Speciality Petrochemicals | Year: 2010
The Cu-AC supported catalyst for dimethyl carbonate (DMC) synthesis by direct oxidative carbonylation of methanol was studied in a continuous fixed-bed reactor. Effects of cupper valence states, impregnation solvents, cupper content and modification of the activated carbon (AC) support were investigated. The results showed that the Cu-AC catalyst prepared using ammonia as impregnation solvent, CuCl as active component and activated carbon as support showed high catalytic activity and DMC selectivity. When Cu content was 7.5%, the catalytic activity was the highest. Excessive cupper in the catalyst resulted in more CuO enrichment on the surface of the catalyst, and then further resulted in the decrease of DMC selectivity and yield. Chemical modification of cola-based AC using CuCl 2 as activator increased the mesopore distribution and changed the range of the pore diameter: the pore distribution changed mainly from 1.5 nm micropore region to 2.5 nm mesopore region. AC with the highest proportion of mesopore distribution at about 2.5 nm pore diameter was appropriate for the dispersion of the active component and improvement of the catalytic activity of methanol oxycarbonylation. On the catalyst with 5% cupper content, methanol conversion, DMC selectivity and space time yield (STY) reached 35.0%, 95% and 211.9 g/(kg · h), respectively.
Wang Z.,Ministry Province Co Cultivated State Key Laboratory Base of Natural Gas Conversion |
Wang Z.,Ningxia University |
Chen J.,Ministry Province Co Cultivated State Key Laboratory Base of Natural Gas Conversion |
Chen J.,Shenhua Ningxia Coal Industry Group Co. |
And 3 more authors.
Shiyou Xuebao, Shiyou Jiagong/Acta Petrolei Sinica (Petroleum Processing Section) | Year: 2011
Core-shell zeolite composite HZSM-5/Silicalite-1 was synthesized via hydrothermal procedure with continuous stirring, and characterized by XRD, SEM, NH3-TPD and Py-IR. Methylation of toluene with methanol to p-xylene over HZSM-5/Silicalite-1 core-shell zeolites in continuous flow fixed-bed reactor was carried out to evaluate the catalytic activity of HZSM-5/Silicalite-1.It was proved that HZSM-5/Silicalite-1 was really a core-shell zeolite composite with a core of HZSM-5 and a shell of Silicalite-1, and the Silicalite-1 shell reached 86%. A reduction of the acid sites and strength could also be achieved by epitaxial overgrowth of Silicalite-1 on the precursor ZSM-5 crystals, showing that HZSM-5/Silicalite-1 possessed high catalytic activity and the selectivity to p-xylene. The toluene conversion and p-xylene selectivity reached 28.1% and 74.3%, respectively.
Wang L.,Ministry Province Co cultivated State Key Laboratory Base of Natural Gas Conversion |
Wang L.,Coal Chemical Company |
Wang Z.,Ministry Province Co cultivated State Key Laboratory Base of Natural Gas Conversion |
An L.,Ministry Province Co cultivated State Key Laboratory Base of Natural Gas Conversion |
And 2 more authors.
Shiyou Xuebao, Shiyou Jiagong/Acta Petrolei Sinica (Petroleum Processing Section) | Year: 2013
P modified ZSM-5/aluminophosphates composite zeolite (wP-ZSM-5/AlPO4-m) was obtained by NH4H2PO4 modification of ZSM-5/AlPO4-m and characterized by XRD, N2 adsorption-desorption, NH3-TPD, FT-IR and so on. The effects of P loaded amount in wP-ZSM-5/AlPO4-m and the reaction conditions, reaction temperature and space velocity, on methanol conversion and product selectivity of MTP were investigated. It was confirmed that the surface area, acid strength and acid amount of wP-ZSM-5/AlPO4-m were effectively regulated by P modification, and the maximum ratio of B acid and L acid reached 3.03 in 3%P-ZSM-5/AlPO4-m, which had the best catalytic activity and stability at the reaction temperature of 500°C and MHSV of 1 h-1. The conversion rate of methanol, selectivity of propylene, molar ratio of propylene and ethylene remained around 100%, 50% and 5, respectively, when the reaction continued for 73 h.