Zn-ZrO2/H-ZSM-5双功能催化剂上合成气转化制汽油馏分的研究

摘要

针对合成气直接转化制汽油馏分反应, 合成了Zn-ZrO2金属氧化物与沸石分子筛复合的双功能催化剂, 结果显示Zn-ZrO2/H-ZSM-5具有较高的CO转化率和汽油馏分选择性.考察了反应温度和接触时间对Zn-ZrO2和Zn-ZrO2/H-ZSM-5双功能催化剂的影响, 证实了合成气经甲醇/二甲醚中间体制汽油馏分的反应路径.研究了Zn/Zr摩尔比、H-ZSM-5分子筛的Si/Al比对催化性能的影响, 结果表明Zn/Zr摩尔比为1:32、Si/Al为200时可获得了较好的转化率 (52％) 和汽油馏分选择性 (62％) , 且催化剂经100h测试稳定性良好.%Hybrid catalysts combined Zn-ZrO2oxide with different zeolites were synthesized and used for the direct conversion of syngas.It was found that the Zn-ZrO2/H-ZSM-5catalyst exhibited higher CO conversion as well as gasoline fuel selectivity than other catalysts.The effects of reaction temperature and contact time on catalytic performances over Zn-ZrO2oxide and Zn-ZrO2/H-ZSM-5were further investigated, and the results suggested that methanol and dimethyl ether intermediates were firstly formed over Zn-ZrO2and then further transformed into gasoline fuel over H-ZSM-5zeolite.The Zn/Zr molar ratio and Si/Al molar ratio of H-ZSM-5over Zn-ZrO2/H-ZSM-5bifunctional catalyst were also studied.The results showed that the Zn/Zr molar ratio at1:32and the Si/Al ratio of H-ZSM-5at 200over Zn-ZrO2/H-ZSM-5were beneficial to the conversion of syngas and the formation of gasoline fuel.Moreover, the catalyst was stable, there was no significant deactivation in 100h.