Development and CommercialApplication of RSDS-II Technology for Selective Hydrodesulfurization of FCC Naphtha

The FCC naphtha selective hydrodesulfurization technology(RSDS-II)has been tested with different feedstocks in pilot scale.The results show that RSDS-II technology is viable in terms of its adaptability to different feedstocks.To produce gasoline with a sulfur content of less than 50μg/g by the RSDS-II technology,the gasoline RON loss is less than 1.8,0.9and 0.2 units,respectively,upon processing the conventional high-sulfur and high-olefin FCC naphtha,the high-sulfur MIP naphtha,and the medium-sulfur or low-sulfur MIP naphtha.Upon using the naphtha produced from pre-hydrotreated FCC feedstock as the RSDS-II feedstock to manufacture gasoline with a sulfur content of lower than 10μg/g,the RON loss does not exceed 1.0 unit.The RSDS-II technology has been commercialized successfully at many refineries.The result of operating commercial RSDS-II unit at the Shanghai Petrochemical Company has revealed that upon processing a feedstock containing 38.7 v% —43.3 v% of olefins and 250—470 mg/g of sulfur,the sulfur content in the treated gasoline ranges from 33μg/g to 46μg/g and the RON loss is equal to only 0.3—0.6 units.Till now this RSDS-II unit has been operating smoothly over 30 months.Thanks to its high HDS activity and good selectivity,the RSDS-II technology can meet the refinery’s needs for adequate upgrading of gasoline.