Cu-H4SiW12O40/γ-Al2O3催化甘油氢解制备1,2-丙二醇

Hydrogenolysis of glycerol to 1, 2-propanediol over Cu-H4SiW12O40/γ-Al2O3

摘要:

采用分步等体积浸渍法合成了Cu-H4SiW12O40/γ-Al2O3催化剂，并研究了其在甘油氢解反应中的催化性能。系统考察了H4SiW12O40的负载量，体积空速对反应的影响，以及催化剂的稳定性。并利用X射线衍射(XRD)、程序升温还原(H2-TPR)和氨气程序升温脱附(NH3-TPD)等手段对催化剂进行了表征。结果表明，较低的体积空速有利于提高甘油的转化率，但对1，2-丙二醇的选择性不利；催化剂上所负载H4SiW12O40的质量分数对甘油转化率影响较大，在H4SiW12O40的质量分数为5%时甘油的转化率达到最大值90.05%；负载型催化剂Cu-H4SiW12O40/γ-Al2O3具有双功能催化性质：同时具有酸中心和金属加氢中心。

Abstract:

The synthesis of 1, 2-propanediol by selective hydrogenolysis of glycerol over the Cu-H4SiW12O40/γ-Al2O3 catalysts in a fixed-bed reactor was investigation. It was found that lower liquid hourly space velocity may promote the glycerol conversion but reduce the selectivity of 1, 2-propanediol. The loading of H4SiW12O40 on the catalyst exhibited a significant on glycerol conversion and a maximum glycerol conversion was obtained at the H4SiW12O40 loading of 5%. NH3-TPD and H2-TPR suggested that Cu-H4SiW12O40/γ-Al2O3 acted as a bi-functional catalyst in the reaction: glycerol dehydration to dehydrated intermediates over H4SiW12O40/γ-Al2O3 and the following hydrogenation over Cu.