Enhancement of catalytic activity of PAl-NaX catalyst for side-chain alkylation of toluene with methanol: Effects of dehydrogenation component Cu

Abstract

Activation and desorption of the hydrogen atom in the toluene methyl is a restrictive step for side-chain alkylation of toluene with methanol (SATM). In this work, two dehydrogenation strategies were used to improve the catalytic performance, dehydrogenation component Cu was introduced in PAl-NaX catalyst as well as the acid-base property was adjusted by changing NaOH loading amount. The relationship among the percentage of acid-base sites, low valence Cu species and the catalytic performances was investigated combined with the multiple characterizations, like X-ray photoelectron spectroscopy (XPS), Temperature-programmed desorption (TPD) of NH3 and CO2, etc. together with ternary regression analysis. It is found that the dehydrogenation component Cu, especially low valence Cu species, promotes the selectivity of side-chain alkylation products to a certain degree, but base sites play an even more critical role in enhancing it.