摘要
Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous catalysts.Here,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce m-DEB.The results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore ZSM-5.And then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion method.The acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid sites.As a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB selectivity.The catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with ethanol.The present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.
基金
Research support is from the Service Local Project of the Education Department of Liaoning Province(LJKMZ22021404,LF2019002 and LJKMZ22021423)
the“Transformational Technologies for Clean Energy and Demonstration”,Strategic Priority Research Program of the Chinese Academy of Sciences,(XDA 21030500).
