羧酸改性SBA-15催化甘油氢氯化合成二氯丙醇的研究

Preparation of dichlorohydrin from glycerol using carboxyl functionalized SBA-15 as catalyst

采用一步共缩合法制备了一系列羧酸改性的SBA-15催化剂(COOH-SBA-15),并将其应用于甘油氢氯化制备二氯丙醇的反应。通过XRD、BET和滴定分析对COOH-SBA-15的结构进行表征,结果表明,采用一步共缩合法可以将羧酸基嫁接到SBA-15的孔壁,并且很好地保持了SBA-15的介孔结构。COOH-SBA-15催化剂在甘油氢氯化反应中表现出良好的催化活性和选择性,其中羧酸嫁接摩尔分数为20%的催化剂活性最好。催化剂重复使用5次后活性略有降低,采用一定浓度的硫酸溶液进行处理,催化剂的活性得到恢复,表明该催化剂具备良好的稳定性和可再生性。

A series of carboxyl functionalized SBA-15 is prepared by co-condensation.The synthesized mesoporous molecular sieve is characterized by XRD,BET and titration.The results suggest that carboxylic acid groups have been grafted onto the pore wall of SBA-15 and retained both structural and textural properties of SBA-15.SBA-15-COOH has higher activity and selectivity in the glycerol-based process.When the mole fraction of the carboxyl group is 20％,the catalyst exhibits the best activity.The catalyst performance has a slightly drop after being reused for five times,but the catalytic activity can be recovered by refluxed with sulphuric acid,which indicates that the catalyst has the stability and regeneration.