DEEP CATALYTIC CRACKING PROCESS FOR LIGHT-OLEFINS PRODUCTION

The newly developed process, Deep Catalytic Cracking (DCC) is a petrochemical extension of FCC for propylene and light isoolefins production. For maximum propylene operation, the propylene yield can be as high as 23 wt% (feed basis). In maximized isoolefin mode, both isobutylene and isoamylene yield can be over 6 wt%. The ratio of isobutylene to total butenes reached 0.42 which was close to the thermodynamic equilibrium value 0.44 at operation temperature. The isoamylene ratio was also near equilibrium. A demonstration unit was started up in 1990 and the results verified the pilot plant data. The effects of principal variables, such as feedstock, catalyst, reaction temperature, severity and hydrocarbon partial pressure are discussed.