Fossil fuel desulfurization

ION-RADICAL ORGANIC CHEMISTRY IN ITS CONTRIBUTIONS TO WOOD DELIGNIFICATION AND FOSSIL-FUEL DESULFURIZATION... 

Desulfurization removal of sulfur from fossil fuels to reduce pollution. 

During the early 1990s IGT collaborated with EBC to develop the BDS process. The combined results from the two companies produced a series of patents describing the process for desulfurization of fossil fuels [237-240], Compared with the patent described in the earlier paragraph [235], these later patents propose a more realistic approach to desulfurization. The basis of these patents is the fact that some of the organosulfur compounds in petroleum are not desulfurized during hydrodesulfurization (HDS), but may be susceptible to BDS. 

Finnerty, W. R., and Robinson, M., Microbial desulfurization of fossil fuels A review. Biotechnol. Bioengineer. Symp., 1986. 16 pp. 205-221. 

Olson, G. Microbial catalyst for desulfurization of fossil fuels. Patent No. US6124130. 2000, Sep. 26. 

Jang, H.-N., Son, H.-Y., Jang, J.-H., et al., A novel klebisiella oxytoca which removes sulfur from fossil fuel that contains organic sulfur compound and desulfurizing method. Patent No. KR205255. 1999, July 01. 

Izumi, Y., and Ohshiro, T., Purification and characterization of enzymes involved in desulfurization of dibezothiophene in fossil fuels. Journal, of Molecular Catalysis B-Enzymatic, 2001. 11(4-6) pp. 1061-1064. 

Vazquez-Duhalt, R. Bremauntz, M. D. P. Barzana, E., and Tinoco, R., Enzymatic oxidation process for desulfurization of fossil fuels. Patent No. US6461859. 2002, Oct. 08. 

Monticello, D. J., Multistage System for Deep Desulfurization of Fossil Fuels Patent No. WO9216602. 1992, Oct. 01. 

Monticello, D. J. Process for the desulfurization and the desalting of a fossil fuel. Patent No. US5496729. 1996, March 05. 

Ortego, B. C. Squires, C. H. Childs, J. D., et al., Method of desulfurization of fossil fuel with flavoprotein. Patent No. WO9617940. 1996, June 13. 

Two strains were isolated and purified, Pseudomonas sp. CDT-4, and Nocardia aster-oides, CDT-4b (ATCC 202160 and 202161, respectively). The microbes were passed through a multiple screen, first to allow growth on dibenzothiophene (DBT) as a sole source of sulfur, and then on fossil fuels, to identify organisms capable of desulfurization without metabolizing the DBT phenyl ring structures. N. asteroides sp. CDT-4b was found to metabolize DBT. The Pseudomonas species was found to utilize trace levels of sulfate from media and was found to be incapable of growth on DBT as a sole source of sulfur. However, the co-culture could remove more than 20% sulfur, with supplementation of a second sulfur-free carbon source. 

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 recombinant DNA molecule from Rhodococcus origin encoding a biocatalyst capable of desulfurizing a fossil fuel. 

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. 

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