Sorbents for Desulfurization of Gasoline Blends

Conventionally, deep desulfurization in a refinery is accomplished by a multi-step process including, hydrodesulfurization (HDS) over CoMo/Al203 and NiMo/AL203 catalysts and subsequent removal of the H2S. However, the HDS process is not suited well to produce ultra clean (essentially sulfur free) transportation fuels. At he severe reaction conditions required for deep desulfurization, the olefins and aromatics in the gasoline become saturated, decreasing the octane number and value of the fuel. TDA Research, Inc. (TDA) proposed to develop a low cost, high capacity sorbent that directly removes the organic sulfur from gasoline blend stocks, producing a fuel the meets the new 30ppm sulfur specification for gasoline. In Phase I, we will prepare various sorbent formulations and screen then to determine their capacity to remove sulfur under representative conditions. Based on the performance results, we will carry out a preliminary design of the desulfurization system and estimate its size and cost. We will also carry out an engineering assessment to evaluate its merits. To reduce the emissions of environmental pollutants, the U.S. Environmental Protection Agency has announced new regulations that require refineries to reduce sulfur levels in the transportation fuels; the allowable sulfur in gasoline is being reduced form 330 to 20 ppmw in diesel by 2006. TDA¿s technology will supply U.S. refineries with a cost-effect sulfur removal technology that helps them to meet the EPA target, and the even lower target the will likely be implemented in the future.