以HZSM-5为活性组分,硅溶胶或铝凝胶为黏结剂,高岭土为载体,制备成型催化剂,用于甘油脱水反应,制备丙烯醛.结果表明:硅溶胶更适合甘油脱水反应体系;以磷酸改性HZSM-5为活性组分的成型催化剂具有良好的机械强度和水热稳定性,经过适当水热处理后表现出优秀的反应性能,在350℃下,以50%甘油水溶液为原料,甘油几乎完全转化,丙烯醛的选择性达到44%,优于目前报道的分子筛上的甘油脱水反应结果;甘油脱水反应中分子筛催化剂的失活主要是由焦炭的堵孔作用造成的.%Shaped catalysts based on HZSM-5 were prepared by using kaolin clay as support and silica sol or alumina gel as binder, which were then used to catalyze the dehydration of glycerol and to prepare acrolein. The results show that silica sol is superior to alumina gel as binder. Shaped catalyst based on phosphorous-modified HZSM-5 shows excellent mechanical strength and hydrothermal stability and good catalytic performance for the dehydration of glycerol after hydrothermal treatment. Approximately 44％ selectivity of acrolein at almost full conversion of glycerol was obtained at 350 ℃ by using 50％glycerol aqueous solution as feed, which is better than any other result ever published for a zeolite catalyst. The formation of coke in the channel of zeolite is the main cause for the rapid deactivation of catalysts.
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