Novel gold catalysts for the direct conversion of ethanol into C_(3+) hydrocarbons

摘要

The catalytic properties of the M/Al_2O_3 (M = NiO, Au, NiO/Au) catalysts were investigated during the conversion of ethanol into C_(3+) hydrocarbons at 623 K. The NiO clusters with a size of 3.5 nm possess low selectivity (12.73%) and low turnover frequency (TOF) 0.051 s ~(-1). By decreasing the size of the Au particles from 15.1 to 5 nm, the TOF increased from 0.095 to 0.384 s~(-1). The reaction with the 5-nm Au particles afforded C_(3+) hydrocarbons with a selectivity of 11.69%. Growing the Au particles by aggregating and/or forming the mixed NiO/Au particles resulted in an increased C_(3+) hydrocarbons selectivity, up to 34.19%. The peculiarities of the reaction mechanism are discussed, with the specific surface and electronic features of the prepared catalysts being considered.