TARGETED DESULFURIZATION PROCESS AND APPARATUS INTEGRATING GAS PHASE OXIDATIVE DESULFURIZATION AND HYDRODESULFURIZATION TO PRODUCE DIESEL FUEL HAVING AN ULTRA-LOW LEVEL OF ORGANOSULFUR COMPOUNDS

摘要

Desulfurization of the hydrocarbon feed is accomplished by flashing the feed at the target cutoff temperature to obtain two fractions. The first fraction contains refractory organic sulfur compounds boiling above the target cutoff temperature. The second fraction boiling below the target cutoff temperature is substantially free of refractory sulfur-containing compounds. The second fraction is brought into contact with the hydrodesulfurization catalyst in a hydrodesulfurization reaction zone operated under mild conditions to reduce the amount of organic sulfur compounds to very low levels. The first fraction is contacted with a gas oxidant on an oxidation catalyst having the formula Cu _x Zn _1-x Al ₂ O ₄ in the gas phase catalytic oxidation zone to convert refractory organic sulfur compounds to SO _x and low sulfur hydrocarbons. Byproduct SO _x is then removed to produce a stream containing reduced levels of organic sulfur compounds.