Selection of carbon catalysts for the industrial manufacture of phosgene

An approach to the evaluation of carbon catalysts suitable for the industrial manufacture of phosgene is described. Relative reactivity and the oxidative stability of catalysts have been measured in laboratory microreactors. Comparison of the performance of full size catalyst pellets versus that of crushed catalyst allowed catalyst effectiveness factors and therefore effective gas diffusivities to be estimated. These data have been combined with a 2-dimensional model incorporating a description of heat and mass transfer to predict catalyst performance in industrial scale phosgene reactors.