Highly active and heat-resisting strong acid-promoted W/HZSM-5-based catalysts, W-Zn (La, Nb)-H2SO4/HZSM-5, for non-oxidative dehydro-aromatization of methane have been developed. Over a W-Zn-H2SO4/H2SO4/HZSM-5 cataly...Highly active and heat-resisting strong acid-promoted W/HZSM-5-based catalysts, W-Zn (La, Nb)-H2SO4/HZSM-5, for non-oxidative dehydro-aromatization of methane have been developed. Over a W-Zn-H2SO4/H2SO4/HZSM-5 catalyst and under the reaction conditions of 1 123 K, 0. 1 MPa, and GHSV=1 500 mL/h per gram cat., methane conversion (XCH4) reached 23%, with a selectivity to benzene at 97% and an amount of coking for 3 h operation at 0. 02% of the weight of the catalyst used. During a stability test at 1 073 K for 3 h, XCH4 had been maintaind at about 21.5% over the W-Zn-H2SO4/HZSM-5 catalyst,whereas dropped gradually to 13% from 19％ in the initial stage over the Mo-Zn-H2SO4/HZSM-5, demonstrating that the former has a better heat-resisting peculiarity than the latter. The results of investigation of optimization of the catalyst composition showed that the optimal W-loading on the HZSM-5[n (Si)/n (Al)=38] zeolite support was about 2.5％, and that an optimal match-ratio existed among the W and the promoters, Zn (or La or Nb) and H2SO4. The experimental results also indicated that the promoting effects of Zn and La were more pronounced than Nb.展开更多
主要介绍了 Ti 合金在核燃料后处理设备中的应用研究进展。开发 Ti 合金替代超低碳不锈钢作核燃料后处理设备用材料已成为后处理设备用材料的发展方向。目前 Ti-5Ta 钛合金已在日本东海村后处理厂进行了中试运行,它的综合性能评价较好,...主要介绍了 Ti 合金在核燃料后处理设备中的应用研究进展。开发 Ti 合金替代超低碳不锈钢作核燃料后处理设备用材料已成为后处理设备用材料的发展方向。目前 Ti-5Ta 钛合金已在日本东海村后处理厂进行了中试运行,它的综合性能评价较好,在后处理环境中应用也最具前景。印度对其开发的 Ti-5%Ta-1.8%Nb 钛合金进行了腐蚀性能研究,结果表明它比普通低碳不锈钢和硝酸级不锈钢具有更好的耐蚀性。展开更多
文摘Highly active and heat-resisting strong acid-promoted W/HZSM-5-based catalysts, W-Zn (La, Nb)-H2SO4/HZSM-5, for non-oxidative dehydro-aromatization of methane have been developed. Over a W-Zn-H2SO4/H2SO4/HZSM-5 catalyst and under the reaction conditions of 1 123 K, 0. 1 MPa, and GHSV=1 500 mL/h per gram cat., methane conversion (XCH4) reached 23%, with a selectivity to benzene at 97% and an amount of coking for 3 h operation at 0. 02% of the weight of the catalyst used. During a stability test at 1 073 K for 3 h, XCH4 had been maintaind at about 21.5% over the W-Zn-H2SO4/HZSM-5 catalyst,whereas dropped gradually to 13% from 19％ in the initial stage over the Mo-Zn-H2SO4/HZSM-5, demonstrating that the former has a better heat-resisting peculiarity than the latter. The results of investigation of optimization of the catalyst composition showed that the optimal W-loading on the HZSM-5[n (Si)/n (Al)=38] zeolite support was about 2.5％, and that an optimal match-ratio existed among the W and the promoters, Zn (or La or Nb) and H2SO4. The experimental results also indicated that the promoting effects of Zn and La were more pronounced than Nb.
基金supported by the National Natural Science Foundations of China(21476132,51536009,51406109 and 21506118)National High Technology Research and Development Program of China(863 program,2012AA101808)~~
文摘主要介绍了 Ti 合金在核燃料后处理设备中的应用研究进展。开发 Ti 合金替代超低碳不锈钢作核燃料后处理设备用材料已成为后处理设备用材料的发展方向。目前 Ti-5Ta 钛合金已在日本东海村后处理厂进行了中试运行,它的综合性能评价较好,在后处理环境中应用也最具前景。印度对其开发的 Ti-5%Ta-1.8%Nb 钛合金进行了腐蚀性能研究,结果表明它比普通低碳不锈钢和硝酸级不锈钢具有更好的耐蚀性。
