摘要
研究了CO_2/H_2在CuO-ZnO-ZrO_2及CuO-ZnO系列催化剂上低压合成甲醇的反应。结果表明,CuO-ZnO-ZrO_2具有比双组分CuO-ZnO催化剂高得多的活性及选择性。用XRD、紫外漫反射光谱、XPS等测试手段,对实验所用催化剂的结构和表面性质进行了研究,并结合活性测试结果,提出高活性、高选择性的CO_2/H_2合成甲醇催化剂要以Cu和Zn共同存在为前提,反应活性中心是表面Cu_2O和ZnO。Cu^+在ZnO中固相溶液的形成及活性组分与载体的较强相互作用对甲醇的生成有很好的促进作用。
The formation of methanol in the reaction of CO2 with H2 in a flow reactor under low pressure over CuO-ZnO and CuO-ZnO-ZrO2 catalysts was studied. CuO-ZnO-ZrO2 showed much higher activity and selectivity for methanol than CuO-ZnO. The pressure, CO2/H2 ratio, space velocity and temperature all affected the catalytic properties of CuO-ZnO-ZrO2 catalysts. The rate of methanol formation increased with the increase of ZrO2 content. XRD, XPS and ultraviolet diffused reflection spectroscopy were used to characterise the structure, surface and bulk of the catalysts. It was assumed that Cu+/ZnO solid solution existed in Cu-ZnO and CuO-ZnO-ZrO2 catalysts. The active centre of the catalysts and the interaction between the active components and support were discussed.
