PROCESS FOR REDUCING CO AND SO.SUB.X EMISSIONS FROM CATALYTIC CRACKING UNITS

摘要

" " Reduction of CO and SOx emissions from regenerators associated with cyclical fluidized catalytic cracking (FCC) units used to convert hydrocarbon feedstocks into more valuable products is achieved by introducing particles of bastnaesite into the FCC unit. The bastnaesite particles recycle with the catalyst particles successively through a catalytic cracking reaction zone, a stripping zone, and a regeneration zone. The bastnaesite particles react with SOx produced in the regeneration zone of the FCC unit, thereby lowering the SOx content of the flue gas discharged therefrom. in the catalytic cracking and stripping zones of the FCC unit, the bastnaesite particles are at least partially reactivated so that upon returning to the regeneration zone yet more SO2 is removed. The bastnaesite particles also aid in lowering CO emissions from the FCC regenerator by catalysing the reaction between CO and oxygen to yield Co2.