助剂二氧化硅对CO2加氢制备甲醇CuO-ZnO-Al2O3-ZrO2催化剂性能的影响

采用共沉淀法制备了一系列CuO-ZnO-Al₂O₃-ZrO₂(CZAZ)催化剂,用于二氧化碳加氢合成甲醇。通过加入少量的助剂二氧化硅得到了一系列CZAZ/SiO₂改性催化剂。采用XRD、BET、H₂-TPR、NH₃-TPD以及CO₂-TPD等技术进行表征,研究了助剂二氧化硅含量对催化剂的物理化学性质以及组织结构的影响。结果表明,助剂二氧化硅的含量对催化剂的组织结构具有较大的影响。同时评价了该组催化剂参与二氧化碳加氢合成甲醇反应的催化性能。测试结果表明,采用助剂二氧化硅质量分数为4%的改性催化剂,表现出较为优良的催化活性。助剂二氧化硅促进了活性组分氧化铜的分散,并且经过二氧化硅改性的CZAZ催化剂具有更大的比表面积,这些因素都对该催化剂在二氧化碳加氢合成甲醇方面的良好表现起到重要作用。

Effect of promoter silica on performance of CuO-ZnO-Al2O3-ZrO2 catalyst for methanol synthesis from CO2 hydrogenation

Various CuO-ZnO-Al₂O₃-ZrO₂ (CZAZ) catalysts for methanol synthesis from CO₂ hydrogenation were prepared by the co-precipitation method. A small amount of silica was incorporated into CZZ catalyst to produce these modified ternary CZAZ catalysts. The effects of silica on physicochemical and catalytic properties were studied with XRD,BET,H₂-TPR,NH₃-TPD and CO₂-TPD. The properties of catalysts were strongly influenced by the content of SiO₂ used as promoter. The catalytic performance for methanol synthesis from CO₂ hydrogenation was evaluated. CZAZ catalyst modified with 4% SiO₂ exhibited optimum catalytic activity. Silica improved dispersion of CuO and its modified CZAZ catalysts exhibited higher specific surface area,which were confirmed to be responsible for excellent performance for methanol synthesis from CO₂ hydrogenation.