Abstract: DOS catalyst was a catalyst developed for reducing sulfur and olefin contents of FCC naphtha. The commercial trial of DOS catalyst was carried out successfully in the FCC unit of SINOPEC Jiujiang Company. The trial results showed that as compared with olefin reducing catalyst GRV-C, DOS catalyst exhibited higher yields of LPG, naphtha and total liquid products, and lower yields of dry gas and coke; the volume percentage of olefin in naphtha reduced 7.8 points; the sulfur distributed in naphtha reduced 19.4%; the ratio of sulfur in naphtha to sulfur in feed reduced 20.3%. Thus, DOS catalyst possessed high heavy oil crackability, good coke selectivity and having the function to reduce sulfur and olefin contents in cracked naphtha.

Key words: cracking catalyst, gasoline stock, sulfur content, olefin, full scale