Study on direct synthesis of triethoxysilane in a fixed bed reactor
In this paper,the interaction between CuCl catalyst and silica particles is enhanced by vacuum evaporation deposition pre-treatment,which improves the reaction efficiency of direct synthesis of triethoxysilane.The vacuum evaporation deposition is favourable for promoting the deposition of cuprous chloride on the surface of silicon particles,and then the Cu3Si active phase is formed.The cata-lytic activity of pretreated samples was evaluated in a fixed-bed reactor to study the effect of different copper species on the direct syn-thesis of triethoxysilanes.And the effects of influencing factors,such as pretreatment temperature,pretreatment time,and different re-action temperatures on Si conversion,triethoxysilane selectivity and yield were investigated.Under the optimum conditions,the maxi-mum conversion of Si could reach 5.79%,and the triethoxysilane selectivity was 83.48%.The pretreated samples were characterized by XRD and SEM,and the the content of different copper species in the samples were determined with the atomic absorption spectrum,these results show that Cu3Si is the active phase that catalyses the synthesis of triethoxysilane.