Particle size effect on the catalyst attrition in a lab‐scale fluidized bed

Abstract

Catalysts readily suffer from particle attrition in fluidized beds. In this article, a commercial fluid catalytic cracking catalyst was sieved into several particle‐size intervals to investigate the size effect on particle attrition. It is shown that an exponential decay equation presents a suitable description of attrition and that catalyst attrition is dependent on particle size. Steady‐state specific attrition rate decreases with increasing particle size; however, initial specific attrition rate and decay time parameter change irregularly. For comparison of attrition resistances, a long attrition test is required to reach steady‐state attrition, and the steady‐state specific attrition rate is recommended. It is seen that the smallest particle‐size interval is the most seriously attrited, while the two largest particle‐size intervals are the most attrition‐resistant. Furthermore, weak interactions appear among attrition behaviors of different intervals, and a linear combination method is effective to combine all interval samples to predict the attrition of the original full‐sized sample. © 2016 American Institute of Chemical Engineers AIChE J, 63: 914–920, 2017