Crude-Oil-to-Chemicals (COTC) projects to boost capacity

Abstract

A complex series of reactions (Table 7.1) take place when gas oil and/or residue molecules come in contact with 1200 °F to 1400 °F (650 °C–760 °C) FCC catalyst. The distribution of products depends on many factors, including the nature and strength of the catalyst acid sites. Although most of the cracking reactions in the FCC are catalytic, thermal cracking reactions also occur. Thermal cracking reactions are caused by cracking severity, feedstock quality, catalyst properties, non-ideal contact of the oil and catalyst in the bottom of riser, degree of catalyst back-mixing and long residence time in the reactor housing.