A novel preparation method of sulfonic functionalized silica: CH3SO3H as the sulfonic source and Al as the bridge

Abstract

A novel approach is designed to optimize the synthesis of sulfonic-functionalized silica material. Results from 29Si and 27Al NMR suggest that the Al acts as the bridging atom connecting the methanesulfonate and silica matrix. Further pyridine-FTIR spectra followed by catalytic activity tests demonstrate that compared with previous methods, our new approach results in higher Lewis acid site concentration, higher thermal stability and superior catalytic activity. Moreover, the whole catalysis preparation procedure is environmentally friendly. Specifically, the silica matrix is synthesized through hydrolysis of tetraethylorthosilicate employing formic acid as hydro-catalyst, in which no surfactant species or precursors were involved.