Investigation of the affect of catalyst additive on catalytic cracking process

Abstract

The study of using non-traditional feedstock resources for the catalytic cracking process enables the processing of a wide range of raw materials, as well as the possibility of regulating selectivity toward various feedstocks. In this regard, the introduction of a Mo catalyst additive—prepared by mixing paramolybdate solution (PMS) with an activating ammonium sulfide solution—into the selected feedstock for the catalytic cracking process leads to the formation of molybdenum disulfide (MoS₂), which is a conventional hydrotreating catalyst component under cracking conditions. This compound exhibits catalytic activity in hydrogenation and hydrocracking reactions. In the presence of the additive, the optimal process conditions correspond to a temperature of 500 °C and an additive concentration of 0.05 wt%. The introduction of the catalyst additive into the feedstock increases the overall acidity of the catalyst from 23.6 to 47.2 µmol during cracking. Moreover, the acidity level of the catalyst and the ratio of acid sites of different strengths intensify the cracking of the feedstock, thereby facilitating the effective progression of reactions during the process. Keywords: Pyrolysis gas, catalytic cracking, Mo catalyst additive, light gas oil fraction, regeneration, vacuum distillate