Catalytic cracking catalyst for reducing sulfur content in catalytic gasoline

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The newly implemented nationwide \"Control Standards for Hazardous Substances in Motor Gasoline\" as of July 1, 2005, require that the sulfur content in finished gasoline be less than 500 ppm. In recent years, the proportion of domestically processed imported crude oil in our country has been increasing year by year, reaching nearly 50% by 2005. Among them, high-vanadium and high-sulfur crude oils from the Middle East have become the main types of crude oil imported by China. Since sulfides in catalytic cracking gasoline account for over 85% of the total sulfides in the final gasoline, reducing the sulfur content in catalytic cracking gasoline is a key technology for producing clean gasoline. Catalytic cracking catalysts designed to reduce the sulfur content in catalytic gasoline were developed in response to the above situation. Sulfur-reducing catalysts achieve sulfur reduction primarily through measures such as the development of vanadium-containing components that have an adsorptive effect on macromolecular sulfides, as well as the modification of carriers and active components. Currently, sulfur-reduction catalysts include two types: DOS and CGP-2. 1. Catalyst CGP-2 specifically designed for the MIP process to reduce sulfur content in gasoline: The CGP-2 catalyst retains the excellent coke selectivity, strong olefin reduction capability, and good propylene selectivity characteristic of catalysts used in the MIP process; it also possesses sulfur reduction functionality, enabling gasoline produced directly using this catalyst in the MIP process to meet the new gasoline standards implemented in July 2005. The intermediate calibration results from the Cangzhou branch show that when the CGP-2 sulfur-reduction catalyst is used at 50% of the system’s total capacity, it can reduce the sulfur content in catalytically stabilized gasoline by approximately 25%. 2. Catalytic cracking catalysts for reducing sulfur content in gasoline: The DOS catalyst is an additive designed to lower the sulfur content in catalytic cracking gasoline; by improving the properties of the carrier and adjusting the production formula, it meets the requirements regarding physical and chemical properties as well as cost for catalytic cracking catalysts, thereby enabling a more significant reduction in the sulfur content in catalytic cracking gasoline. However, industrial test data show that the cracking ability of the DOS agent and the product distribution are both very good, but the sulfur content in gasoline still needs to be further reduced.