Deactivation and Regeneration of Zeolite Catalysts Used in Pyrolysis of Plastic Wastes—A Process and Analytical Review

In catalytic industrial processes, coke deposition remains a major drawback for solid catalysts use as it causes catalyst deactivation. Extensive study of this phenomenon over the last decades has provided better understanding behavior in great number processes. Among them, pyrolysis plastics, which been identified promising process waste revalorization, is given particular attention paper. Combined economic and environmental concerns rose necessity to restore activity by recovering deactivated catalysts. Consequently, various regeneration processes have investigated years development an efficient sustainable challenge. Coke removal can be achieved via several chemical such oxidation, gasification, hydrogenation. This review focuses on oxidative treatments regeneration, covering current progress oxidation presenting advantages drawbacks each method. Molecular with oxygen ozone, well advanced formation OH radicals, are detailed provide deep mechanisms kinetics involved (direct indirect reaction rates selectivity, diffusion, mass transfer). Finally, paper summarizes all relevant analytical techniques that used characterize regenerated catalysts: XRD, N2 adsorption-desorption, SEM, NH3-TPD, elemental analysis, IR. Analytical classified according type information they provide, structural characteristics, composition, or properties. function property, overall tool useful easy-to-use determine adequate analysis.