Methods for laboratory-scale evaluation of catalyst life in industrial plants

Abstract

After having defined the main types of deactivation causes responsible for decreased catalyst life in industrial plants (chemical and depositive poisoning, thermal and chemical sintering, solid state reactions, loss of active components), the requisites of reliable life tests are discussed. It is shown that relative accelerated tests are needed: two different types of tests can be used, defined here as “Continuous” and “Before-After” tests, respectively abbreviated as C and BA tests. The need of preliminary studies of deactivation mechanisms is stressed and the experimental techniques to be used in such studies,depending on the cause of deactivation,are mentioned. The criteria to be followed for the development of accelerated life tests are discussed for each deactivation cause and suggestions are given for the choice of the test procedure. The special cases of fluid-bed and slurry catalysts are also briefly discussed. Finally, the evaluation of catalyst resistance to plant malfunctioning and the expected shortcomings of accelerated life tests are examined.