本文制备了一系列Ag/Al2O3(Li2O)/g-C3N4复合催化剂，考察了其可见光催化乙醇制取环氧乙烷的性能。Li2O可调变Al2O3表面的酸性，从而降低了主要副产物乙醛的选择性。Ag/Al2O3(Li2O) 在g-C3N4上的负载量对产物环氧乙烷的选择性有较大影响，当Ag/Al2O3(Li2O) 负载量为5wt%时，乙醇具有较高的转换率，且环氧乙烷的选择性高达100%。
A series of Ag/Al2O3(Li2O)/g-C3N4 catalysts were prepared, and their performances for photocatalytic conversion of ethanol into ethylene oxide (EO) were investigated under visible light irradiation. Li2O can adjust the acidity of Al2O3 surface, effectively, so as to reduce the selectivity of the main by-product acetaldehyde. The selectivity of EO was notably influenced by the loading amount of Ag/Al2O3(Li2O) on g-C3N4, which reaches 100% with high ethanol conversion when the loading amount of Ag/Al2O3(Li2O) was 5wt%.
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