This Symposium on Catalyst Deactivation ensues those held at Berkeley (1985), Antwerp (1980) and Berkeley (1978).The three main topics emphasised at this most recent symposium were: the techniques used in deactivation studies, the mechanisms of catalyst deactivation, and modelling. With respect to the first, it became apparent that the study of deactivation faces even more difficulties than the characterization of fresh catalysts and the measurement of activity or selectivity, due to the multiplicity of interacting processes occurring during deactivation. Quite substantial progress has been made recently in the understanding of the mechanisms of various deactivation processes, particularly coking, and extra time was accorded to these topics at the symposium. The third topic corresponds to a problem which is very central to development studies and to the chemical engineering aspect of catalysis: it deals with the representativity of accelerated tests and the modelling of the deactivation phenomena.
