Agglomeration and adhesion of catalyst particles in gas-liquid reactors

The colloidal properties of catalysts present in three phase slurry reactor s may affect the overall behaviour of such a reactor. In part, this may ari se from the adhesion of such particles to gas bubbles, which may lead to en hancement of the G-L mass transfer [Catal. Today 48 (1999) 131]. Classical film theory based on the mass transfer models are capable of quantitatively predicting such mass transfer enhancement, but only on the basis of a prio ri knowledge of the degree of bubble coverage by particles. Presently, vari ous methods are reviewed that allow the accurate experimental determination of the coverage of bubbles by particles, under both stagnant and non-stagn ant conditions. The relevance of these phenomena to reactive systems will b e demonstrated on the basis of mass transfer data for the hydrogenation of methyl acrylate in a slurry reactor. (C) 2001 Elsevier Science B.V. All rig hts reserved.