摘要
以超临界干燥法制得的超细ZrO2为载体,浸渍铜后所得的CuO/ZrO2催化剂对CO/H2合成甲醇呈现出较好的活性和选择性.反应温度对催化剂的活性和选择性有较大的影响.XPS结果表明,载体和活性组分间存在着相互作用.TPR结果说明CuO/ZrO2中的铜以两种形式存在,一种为体相铜,另一种为高度分散的铜.后者的含量和甲醇产率存在着顺应关系,它应是关键的活性组分.
uO/ZrO2 catalysts exhibit good activity and high selectivity for methanol synthesis from CO/2H2. The catalysts were prepared by impregnation and ultra-fine ZrO2 support was dried by supercritical drying method. Reaction temperature influences the activity and selectivity for this reaction in greater level than pressure does.The maximum conversion of carbon monoxide to methanol was obtained at 275℃ The steady state activity was reached after about fifteen hours of reaction and maintained for over forty hours. It was found from XPS results that interaction between copper and support existed. TPR revealed that there were two kinds of CuO in the catalysts: one was bulk CuO and the other was easy to be reduced one. The productivity of methanol increases with the increase of the content of the latter, so it is likely that the latter one is the key component of the catalysts for the reaction activity. XRD spectra gave only the diffraction peak of metal copper and Cu2O could not be found in reduced and used catalysts.
关键词
二氧化锆
氧化铜
甲醇合成
催化性能
zirconia,copper oxide,methanol synthesis, supercritlcal drying