Selective Synthesis of Triethoxysilane and Tetraethoxysilane through Direct Reaction between Ethanol and Silicon Catalyzed by CuCl and Metallic Cu0 Nanoparticles in Fixed-bed Reactor

Abstract

The selective synthesis of triethoxysilane and tetraethoxysilane through the direct reaction between ethanol and silicon was catalyzed by CuCl and Cu0 nanoparticles in a fixed-bed reactor. When CuCl/Si mixture was pretreated in a N2 stream, metallic Cu0 phase appeared at 260–500 oC and Cu3Si phase appeared at 280–500 oC. When CuCl/Si mixture was pretreated at 240–300 oC, triethoxysilane was favorably formed while pretreated at 500 oC, tetraethoxysilane was favorably formed. Small-sized CuCl exhibited higher catalytic activity than the larger one. Cu-Si-Cl complex was probably the active site for the formation of triethoxysilane whereas metallic Cu0 crystallite was the active site for the formation of tetraethoxysilane.