WO3-based catalysts prepared by non-hydrolytic sol-gel for the production of propene by cross-metathesis of ethene and 2-butene

Abstract

One-step non-hydrolytic sol-gel (NHSG) route is presented as a powerful method to prepare highly effective alkene metathesis catalysts. Tungsten-based catalysts are the industrially relevant system and are prepared for the first time using NHSG. The catalysts were characterized by N2-physisorption, XRD, NH3-TPD, NH3-chemisorption, XPS, TPR, ICP-AES and evaluated in the cross-metathesis of ethene and trans-2-butene to propene. These new catalysts are systematically compared with reference catalysts prepared by impregnation methods on 2 commercial supports (silica and silica-alumina). NHSG catalysts markedly outcompete reference impregnated catalysts in terms of conversion, selectivity and stability. Characterization results show that the texture, tungsten dispersion, reducibility and surface acidity of the NHSG catalysts depend strongly on their composition. This in turn can be correlated with the catalytic performance.