Using spent catalyst from refinery FCC units to produce 4A-zeolite: synthesis, procedure, and kinetics

A study was carried out on the possibility of using the spent catalyst from refinery fluidised catalyst cracking (FCC) units to produce 4A-zeolite. The resulting 4A-zeolite exhibited a crystallinity exceeding 90%, had an ion exchange capacity resembling that of commercial products, and a whiteness index and particle size distribution within recommended limits for use as a water softening additive by Ca2+ ion absorption.