| 摘要 |
A process for the deep desulfurisation of hydrocarbons (HC), in particular Natural Gas Condensate (NGC), and HC comprising diesel, pre-extracted diesel and naphtha, is described which is capable of reducing the sulfur content of these HC from 500 to 30 ppm. The process comprises contacting the hydrocarbon material with an oxidant selected from organic peroxy acids, organic peroxides, inorganic peroxides and mixtures thereof, in at least a stochiometric amount sufficient to oxidise a sulfur compound to a sulfone compound; contacting the hydrocarbon material with an aqueous extractant to allow at least a portion of the oxidised sulfur compounds to be extracted into the aqueous extractant, and separating the hydrocarbon material from the aqueous extractant to give a hydrocarbon material of reduced sulfur content. Optionally, the process may include a second and subsequent extractions with the aqueous extractant to further reduce sulfur content. A final extraction with an IL may be conducted. The invention also provides for substitution of the aqueous extractant with an IL in one or more of the other extraction steps. The extractants and by products generated during f01 oxidation can be recovered by simple distillation techniques. |
| 主权项 |
1. A process for reducing the sulfur content of a hydrocarbon material containing sulfur compounds to ultra low sulfur levels of <15 ppm, the process comprising:
at least one oxidation step comprising contacting the hydrocarbon material with an oxidant thereby providing oxidized sulfur compounds; a first extraction step comprising contacting the hydrocarbon material with an aqueous extractant selected from water or brine to allow at least a portion of the oxidized sulfur compounds to be extracted into the aqueous extractant, and separating the hydrocarbon material from the aqueous extractant to give a hydrocarbon material of reduced sulfur content, wherein the oxidant is in stoichiometric excess in an amount of about 10-20 molar equivalent based on the sulfur content of the hydrocarbon material, wherein the first extraction step is followed by one or more extraction steps with an extractant selected from an aqueous extractant of and an ionic liquid (IL) and wherein at least one of the one or more extraction steps following the first extraction step is conducted with an ionic liquid and a final extraction step is conducted with an aqueous extractant, wherein the ionic liquid (IL) is an IL of general composition Q+A−, wherein Q+is a quarternary ammonium or phosphonium cation and A−is selected from any one of an alkylsulfate anion, an alkylsulfonate anion, an aromatic sulfonate anion, a thiocyanate anion, a bis(trifluormethanesulfonyl)imid anion, or a combination of two or more of such anions, and optionally A−is selected from one or more anions selected from any one of a halide anion, a nitrate anion, a perfluroalkylcarboxylate anion, a hexafluorophosphate anion, an organophosphorous anion, a tetrafluoroborate anion, a carboxylic acid chelated borate anion, a dicyanamide anion, a halogenoaluminate anion or an organohalogenoaluminate anion or a combination of two or more of such anions, selected such that the IL is in a liquid state at the operating temperature and pressure of the process , and wherein the hydrocarbon material containing sulfur compounds is obtained from a refinery stream and is selected from the group consisting of natural gas condensates, light oils, diesel, gasoline, petroleum, jet fuels, and products of coal gasification and liquidification. |
