摘要
本文分别采用ＸＲＤ、ＥＳＲ、ＸＰＳ和ＸＡＥＳ等技术对于二氧化碳加氢低压合成甲醇用ＣｕＯ，ＣｕＯ－ＺｎＯ，ＣｕＯ－ＺｎＯ－Ａｌ＿２Ｏ＿３，ＣｕＯ－ＺｎＯ－ＺｒＯ＿２催化剂在不同条件下表面Ｃｕ、Ｚｎ、Ａｌ、Ｚｒ的存在价态进行了深入分析。实验发现催化剂在还原前Ｃｕ以Ｃｕ￣２＋存在，在还原后和反应状态下以Ｃｕ￣０存在；Ｚｎ在还原后和反应状态下有部分被还原为Ｚｎ￣（２－δ）（０＜δ＜２），Ｚｒ和Ａｌ仍保持其还原前价态。催化剂的表面化学组成为：Ｃｕ￣０／Ｚｎ（２－δ）￣＋／Ｚｒ￣４＋／Ａｌ￣３＋／Ｏ￣２－。
The surface cbemical state of Cu、Zn、Zr and Al in CuO、CuO-ZnO、CuO-ZnO-ZrO_2 and CuO-ZnO- Al_2O_3 catalysts for methanol synthesis from carbon dioxide and hy-drogen,had been examined by XRD、ESR、XPS and XAES under various conditions,It has been found that copper is bivalent before reduction and zero valant after reduction and under reaction condition.A part of Zn￣(2+) is reduced to Zn￣(2-δ)+(0<δ<2)after reduction and under reaction condition.Zr￣(4+) and Al￣(3+) retain their original valance state under various conditions.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1994年第2期176-182,共7页
Journal of Fuel Chemistry and Technology
关键词
二氧化碳
甲醇
氢化
金属催化剂
carbon dioxide,hydrogenation,methanol,catalyst,metal oxide
