DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH

Abstract

Due to the increasingly stricter regulations for deep reduction of fuel sulfur content, development of new deep desulfurization processes for liquid transport fuels has become one of the major challenges to the refining industry and to the production of hydrocarbon fuels for fuel cell applications. The sulfur compounds in the current transport fuels corresponding to the S level of 350-500 ppm account for only about 0.12-0.25 wt % of the fuel. The conventional hydrotreating approaches will need to increase catalyst bed volume at high-temperature and high-pressure conditions for treating 100 % of the whole fuel in order to convert the fuel mass of less than 0.25 wt %. In the present study, we are exploring a novel adsorption process for desulfurization at low temperatures, which can effectively reduce the sulfur content in gasoline, jet fuel and diesel fuel at low investment and operating cost to meet the needs for ultra-clean transportation fuels and for fuel cell applications. Some adsorbents were prepared in this study for selective adsorption of sulfur compounds in the fuels. The adsorption experiments were conducted by using a model fuel and real fuels. The results show that the adsorbent (A-1) with a transition metal compound has a significant selectivity for sulfur compounds with a saturated adsorption capacity of {approx}0.12 mol of sulfur compounds per mol of the metal compound. Most sulfur compounds existing in the current commercial gasoline, jet fuel and diesel fuel can be removed by the adsorption using adsorbent A-1. On the basis of the preliminary results, a novel concept for integrated process for deep desulfurization of liquid hydrocarbons was proposed.