Toward a Generic Model for Phosgene Synthesis Catalysis over Activated Carbon

Abstract

A reaction model was recently been postulated to describe the phosgene synthesis process over an activated carbon catalyst. That body of work exclusively considered a single grade of activated carbon (Donau Supersorbon K40), raising the issue that the mechanistic insight gleaned could be restricted to the single substrate. Therefore, to evaluate the generality of the proposed sequence of elementary reactions that lead to phosgene production, this article concentrates on Norit RX3 Extra, a representative activated carbon that finds wide application in industrial applications. Several phosgene synthesis traits were associated with Donau Supersorbon K40 and are reproduced with Norit RX3 extra over the reaction conditions studied, such as exclusive phosgene selectivity and a degree of reagent retention. However, temperature‐programmed reaction studies show the reaction profile of the Norit RX3 extra to exhibit deviations from that observed for Donau Supersorbon K40. A modified reaction model is proposed to account for these differences. The revised reaction model is thought to represent a generic model for phosgene synthesis that can accommodate disparities in the surface chemistry of different activated carbon formulations.