The Benefits of Cat Feed Hydrotreating and the Impact of Feed Nitrogen on Catalyst Stability;

摘要

This paper deals with the objectives and constraints of pretreating feedstocks for fluid catalyticrncracking. It will look at the chemistry involved and, based upon new insights, will consider feedrnnitrogen and its impact on the selection of catalyst type for the most stable performance.rnCurrently, there is a growing need to refine heavier and tougher crude oils with an increasedrnnitrogen content and other contaminants such as polyaromatics, metals, arsenic and silicon.rnTherefore, not only hydrodesulfurization (HDS) is very important, but also hydrodenitrogenationrn(HDN) has become a critical hydroprocessing reaction which provides more insight into catalystrnstability. In the present paper, we discuss the different nitrogen compounds found in highrnnitrogen feedstocks to FCC pretreat which we have identified using gas chromatography withrnatomic emission detection (GC-AED). Our findings can be related to several studies usingrnmodel feedstocks which show that in particular basic nitrogen-containing molecules inhibit HDSrnreactions the most. We will discuss factors that impact the catalyst stability, and finally we willrnshow data from industrial units.