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采用浸渍法对HY/SBA-15微孔介孔复合分子筛进行Ce改性,制备了催化剂Ce-HY/SBA-15。X射线衍射和高倍透射电镜的表征结果表明,Ce改性后的催化剂保持了HY/SBA-15微孔、介孔结构,Ce离子均匀地分散在分子筛的孔道里,没有出现团聚;Py-FTIR和NH3-TPD的表征结果表明,Ce的负载使羟基表现出更强的B酸强度。以Ce-HY/SBA-15为催化剂催化合成乙酸正丁酯,通过实验确定了较佳的制备条件:反应时间为2.0 h、酸醇物质的量比为1∶1.2、催化剂质量分数为10%时酯化率最高,并考察了三种分子筛催化剂的重复使用性能,结果证明了Ce的负载和HY的结构有利于提高催化剂的酸催化活性。
Ce-HY / SBA-15 catalyst was prepared by impregnation of HY / SBA-15 microporous mesoporous composite molecular sieve Ce. X-ray diffraction and high-power transmission electron microscopy showed that the Ce modified catalyst retained the HY / SBA-15 micropores. The mesoporous structure and Ce ions were uniformly dispersed in the pores of the molecular sieve without agglomeration. Py-FTIR And NH3-TPD characterization results show that the load of Ce makes the hydroxyl group show a stronger B acid strength. Catalytic synthesis of n-butyl acetate with Ce-HY / SBA-15 catalyst showed that the best preparation conditions were as follows: the reaction time was 2.0 h, the molar ratio of alcohol to alcohol was 1: 1.2, the mass fraction of catalyst was 10% The esterification rate was the highest, and the reusability of the three molecular sieve catalysts was investigated. The results showed that the loading of Ce and the structure of HY were beneficial to improve the acid catalytic activity of the catalyst.