Conversion of 2-methylfuran to 2-methylthiophene over alkaline X- and Y-zeolites

Abstract

The activity of M^I-Y and -X zeolites (M = Li, Na, K, Rb, Cs) in catalysing the title reaction has been analysed together with some relevant physico-chemical characteristics of the catalyst. Some useful correlations, extending to both the series of alkali-metal cation X and Y faujasites, have been found between catalyst performance, some structural properties and excess of negative charge on crystal-lattice oxygen of the solid. The selectivity of the process appears to depend on the relative number of H₂S molecules adsorbing through ionic- or radical-type mechanisms onto the catalyst surface and on the relative stability of the intermediates so formed between adsorbed H₂S and the zeolite surface site.