摘要
制备了不同助剂修饰改性的Cu/SBA-15催化剂,利用FTIR,XRD,H_2-TPR和XPS等表征手段对改性的催化剂进行了表征,并考察了催化剂在其他酯加氢反应中的性能。表征结果显示,B和Fe助剂可以增强Cu/SBA-15催化剂在酯加氢反应中的催化选择性,B改性的Cu/SBA-15催化剂可以降低其铜活性中心粒径,提高还原之后的Cu~+含量,从而有利于提高催化反应选择性,而Fe改性的Cu/SBA-15催化剂降低Cu粒径的同时,增加了Cu~0含量,并且对酯类也具有活化作用,从而提高了催化选择性。实验结果表明,B和Fe能够加强Cu/SBA-15催化剂的性能,并且Cu-Fe/SBA-15催化剂可广泛应用于丙二酸二乙酯,草酸二甲(乙)酯和乙酸乙酯加氢反应中。
Cu/SBA-15 catalysts were modified by adding different promoters.The catalysts were systematical characterized by FTIR,XRD,H_2-TPR and XPS methods,and their catalytic performances were tested in ester hydrogenation reactions.The results suggested the B and Fe-doped Cu/SBA-15 exhibit enhanced catalytic selectivity in ester hydrogenation reactions.Specifically,the B-doped Cu/SBA-15 catalyst can reduce the particle size of copper active center and increase the content of Cu~+ after reduction,which is beneficial to improve the selectivity of catalytic reaction However,the Fe-doped Cu/SBA-15 catalyst can reduce the particle size of copper,increase the content of Cu~0,and activate the esters,thereby improving the catalytic selectivity.The results sugges that modified Cu/SBA-15 catalysts show a better catalytic performance and can be wildly used in diethyl malonate,dimethyl/diethyl oxalate and ethyl acetate hydrogenation processes.
引文
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