Study of fluid catalytic cracking catalyst additives for yield enhancement

Abstract

Increasing refinery capacities and diminishing sweet crude reserves has given rise to processing of sour crudes containing sulphur, nitrogen and other impurities in enhanced proportions. Processing of high nitrogenous crudes has detrimental effect on catalyst activity. High nitrogenous crudes which contain nitrogen in the form of basic nitrogen compounds i.e. pyridine, quinoline, aniline affect the acidic sites of the catalyst and eventually decreasing its activity. It is desired that basic nitrogen compounds maybe removed for reducing its effect on the catalyst selectivity. There are various methods available for removing the basic nitrogen compounds such as adsorption of nitrogen on a alumina-silica based catalysts, treating the FCC feed with mineral acids so that it forms water based salts and hydro processing of feed i.e. hydrodenitrogenation of FCC feed. There are various advantages and disadvantages associated with each and every method. In this work effect of basic nitrogen compounds on FCC catalyst activity was studied and a study had been done on few catalyst additives and its effect on catalytic activity in terms of conversion and selectivity. ZSM-5 and commercial BCA had been used as catalyst additives. Inhouse formulated BCA additives were tested for their effect on activity of the catalyst.