Solvent-free reactions of solid substances using solid catalysts: estimation of physical states of substrate–product mixtures by the BET method and the SEM observation

Abstract

Surface area estimations by the BET method and SEM observations were applied to the investigation of the physical states of substrates and products during the solvent-free reactions of solid substances using supported metal catalysts. The solvent-free hydrogenolysis of trans-oxirane-2,3-dicarboxylic acid (trans-epoxysuccinic acid) or its disodium salt and the solvent-free hydrogenation of thymol were used as the sample reactions in this study. These reactions were postulated to proceed in the fused state, based on specific surface areas and micrographs of the catalyst–substrate–product mixtures. This study revealed that the combination of the BET method and SEM observations was a promising tool for the mechanistic investigation of solvent-free reactions.