多级孔结构WO3/ZrO2固体酸催化剂的烷基化催化性能研究

Alkylation Catalysis over the WO_3/ZrO_2 Solid Acid Catalyst with Hierarchically Porous Structure

采用复合模板表面活性剂辅助水热法一步合成WO3/ZrO2体系多级孔固体酸催化剂,探讨了煅烧温度对所合成催化剂试样酸强度及酸量的影响,并考察了催化剂针对苯和十二烯的烷基化反应中的催化性能.结果表明,WO3/ZrO2体系催化剂具有较强的酸强度,并且与催化剂的比表面积和晶化程度有密切关系,比表面积的增大和四方相ZrO2的生成能有效地提高催化剂的酸强度.该催化剂具有优良的烷基化反应催化活性和选择性,其中450℃,5h煅烧的WO3/ZrO2催化剂样品酸性最强,其烷基化催化活性和选择性最优.

Series of WO3/ZrO2 solid acid catalysts with hierarchically porous structure were prepared by the one-pot hydrothermal method involving templating from a composite surfactant.The effect of calcina-tion temperatures of the prepared catalysts on the acid strength was studied as well as the total amount of acidity.The reaction of benzene alkylation with 1-dodecene was chosen as model acid catalysis.The results indicated that the acid strength and the total amount of acidity of the prepared catalysts increased with increasing of surface area and crystallization of t-ZrO2.Such catalyst shows a strong catalytic activity of the alkylation,and both the alkylation conversion and selectivity increase with acid strength.Herein,the catalyst sample calcined at 450 ℃ for 5 h has the highest catalytic activity and selectivity.