The Application Of FCC Gasoline Caustic-Free Sweetening Technics In Karamay Petrochemical Branch Of CNPC

There are mainly two ways to sweeten light oils: removal of mercaptan from the lightoils, and oxidation of mercaptan to less harmful disulfide. In conclusion, there are fourcommercial processes of sweetening: extraction, oxidation, absorption, andextraction-oxidation combination. For more and more residue, the maximum amount was upto 35.8ï¼…, were added to fluid catalytic cracking (FCC) unit of Karamay PetrochemicalBranch of CNPC, the old Merox sweetening process could not meet the specification. In 1998,the caustic-free sweetening(â… ) process was installed in Karamay Refinery, it solved theproblem that the gasoline could not pass the doctor test successfully, however the caustic-freesweetening(â… ) process needed to regenerate the catalyst frequently where much aside alkalilye was released, this threatened the equipments as well as environment greatly. In May 2006,Karamay Refinery upgraded the FCC gasoline sweetening process to the caustic-freesweetening(â…¡) process by using AFS-12 catalyst and HA-20 cocatalyst, which overcame theabove limitations effectively, and achieved relatively good benefits both in economy andenvironment.