Recycling of Spent FCC Catalysts: Conversion of Leached Residues to Zeolite ZSM-5.

The commercial recycling of spent FCC catalyst typically focuses on recovering only 1-3 % of rare-earth elements, with the remaining residues often disposed of in landfills. Here, we present a novel method to close a recycling loop for spent FCC catalyst. The method involves a series of leaching steps: Firstly, the spent catalyst material is leached with HNO to remove rare-earth elements such as La; second, solvothermal leaching with HCl removes most of Al and impurities like Fe, Ni and V; finally, a third leaching with HSO removes Ti.

Crucial Role of Silica-Alumina Binder Mixtures for Hydrocarbon Cracking with ZSM-5 Additives.

Alumina-containing binders are widely used for the binding of catalyst particles by spray drying and calcination. As a part of the active matrix, they contribute to the catalytic performance of the resulting catalyst grain during hydrocarbon cracking. In this study, correlations are investigated using different compositions of Al- and Si-based binders (AlCl and colloidal silica) together with kaolin as a filler and ZSM-5 zeolite as an active compound.

Binder Selection to Modify Hydrocarbon Cracking Properties of Zeolite-Containing Composites.

Activity, selectivity, and deactivation behavior of catalyst materials determine their efficiency in hydrocarbon conversion processes. For hydrocarbon cracking, the industrial catalyst is an important parameter in reaction technology to produce valuable compounds, , light olefins (C-C) and gasoline from crude oil fractions with high molecular weight (C). One strategy to enhance the catalytic activity for precracking is increasing the matrix activity, which depends on the used binder and additives.