Desulfurization of organic sulfur compounds

The desulfurization of organic sulfur compounds with Raney Ni using far greater amounts than a catalytic is not a catalytic hydrogenolysis in the strict sense but involves a stoichiometric chemical reaction, since the catalyst itself is converted into nickel sulfide. However, since it has found many useful applications with Raney Ni (a hydrogenation catalyst), this reaction has been treated in this section. 

It has been reported that metal-zeolite catalysts have high possibility as new hydrodesulfurization catalysts for petroleum [1-9]. The catalytic desulfurization of organic sulfur compounds over zeolites has been investigated systematically [10-12]. On the basis of fundamental catalytic studies, active zeolite-based hydrodesulfurization catalysts such as transition metal ion-exchanged Y zeolites(MeY)[13-16], MoS2/NiHY[17] and Rh/USY[18,19] were developed. 

Ohshiro, T. Izumi, Y. Microbial desulfurization of organic sulfur compounds in petroleum. Biosci. Biotechnol. Biochem. 1999, 62 (1), 1-9. 

Kohler, M. Genz, I.-L. Schicht, B., and Eckart, V., Microbial Desulfurization of Petroleum and Heavy Petroleum Fractions. 4. Anaerobic Degradation of Organic Sulfur Compounds. Zentralbl. Mikrobiol., 1984. 139 pp. 239-247. 

Method for oxidation of organic sulfur compound included in organic compound and method for oxidative desulfurization of fuel oil [104],... 

Kurane, R. Miki, K. Ukekawa, K., and Yamamoto, J., Method for oxidation of organic sulfur compound included in organic compound and method for oxidative desulfurization of fuel oil. Patent No. JP2001151748. 2001, June 05. 

For a review, see Bonner Grimm, in Kharasch Meyers The Chemistry of Organic Sulfur Compounds, vol. 2 Pcrgamon New York, 1966. pp. 35-71, 410-413. For a review of the mechanism of desulfurization on molybdenum surfaces, see Friend Roberts Acc. Chem. Res. 1988,21, 394-400. 

Studies of sulfur-containing organic compounds in coal provide information on the origin of organic sulfur and the transformation of sulfur compounds during coal maturation. The distribution and types of organic sulfur compounds in coal have profound implications for desulfurization processes. 

In this section, a summary of the chemical principles involved with membrane reactors for desulfurization are overviewed. The details will be covered in the following sections. Electrochemical desulfurization technologies assisted by membranes have been extensively explored for the removal of sulfur that exists in sulfur compounds in fossil fuels and in SO2 form in flue gas. In principle, SO2 can be absorbed by an aqueous electrolyte solution and then electrochemically converted into species such as sulfate, hydrogen sulfide, and sulfur, among others, by oxidation or reduction processes, whereas the sulfur compounds in fossil fuels can be similarly removed. The universal reaction mechanism of the electrochemical cathodic reduction of organic sulfur compounds in gasoline and diesel is shown in Eqn (14.1) (Lam et al., 2012) ... 

A variety of organic sulfur compounds, in addition to DBT, were shown to be substrates for desulfurization by IGTS8, including thianthrene, phenyl sulfoxide, trithiane, and benzyldisulfide. In contrast, IGTS8 could not metabolize thianaph-thene, phenyl disulfide, and 2-thiophene-carboxylic acid (50), a similar substrate profile as the Arthrobacter isolate previously described by Knecht. A number of other bacteria have subsequently been isolated that use an analogous pathway and have similar substrate ranges (51-56). 

Because hydrocarbon feeds for steam reforming should be free of sulfur, feed desulfurization is required ahead of the steam reformer (see Sulfur REMOVAL AND RECOVERY). As seen in Figure 1, the first desulfurization step usually consists of passing the sulfur-containing hydrocarbon feed at about 300—400°C over a Co—Mo catalyst in the presence of 2—5% H2 to convert organic sulfur compounds to H2S. As much as 25% H2 may be used if olefins... 

Van Afferden, M. Tappe, D. Beyer, M., et al., Biochemical-Mechanisms for the Desulfurization of Coal-Relevant Organic Sulfur-Compounds. Fuel, 1993. 72(12) pp. 1635-1643. 

Deep desulfurization method of fossil fuels, comprising a first step of HDS and a BDS step for the removal of HDS sulfur refractory compounds, using an effective amount of a biocatalyst. The fuel is incubated in the presence of one or more BDS-active microorganisms, which converts the organic sulfur compounds into water-soluble inorganic sulfur. Then, in a separation stage, the products of the incubation are separated into a deeply desulfurized liquid fossil fuel, and the water-soluble inorganic sulfur. 

A method for simultaneous desulfurization and desalting of fossil fuels by mixing the aqueous biocatalytic solution with the feed under conditions for both processes to occur. Both inorganic salts, the originally present in the fuel and the produced from the conversion of the organic sulfur compounds are solubilized by the added water, resulting in an aqueous phase with a salt concentration greater than 0.5 wt%. The biocatalyst consists of Rhodococcus sp. ATCC 53968, its mutants or cell-free fractions. 

Gordona sp. CYKS1 (KCTC 043 IBP) capable of desulfurizing fossil fuel containing organic sulfur compounds [134],... 

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