Solvent for use in aromatic extraction process

Abstract

Oxidized disulfide oil (ODSO) compounds, derived from disulfide oil (DSO) compounds produced as by-products from the generalized mercaptan oxidation (MEROX) sulfur removal process, are effective as aromatic extraction solvents, thereby converting the low value or waste oil DSO products into a valuable commodity that has utility in improving the extraction of aromatics from hydrocarbons derived from fossil fuels.

We claim: 
     
         1 . An aromatic extraction solvent that comprises one oxidized disulfide oil (ODSO) compounds selected from the group consisting of (R—SOO—SO—R′), (R—SOO—SOO—R′), (R—SO—SOO—OH), (R—SOO—SOO—OH), (R—SO—SO—OH), and (R—SOO—SO—OH), where R and R′ are alkyl groups comprising 1 to 10 carbon atoms. 
     
     
         2 . The aromatic extraction solvent of  claim 1 , wherein the number of carbon atoms in the one or more ODSO compounds is in the range of from 1 to 20. 
     
     
         3 . The aromatic extraction solvent of  claim 1 , wherein the solvent is water soluble. 
     
     
         4 . The aromatic extraction solvent of  claim 1 , wherein the one or more ODSO compounds of the solvent has at least three oxygen atoms. 
     
     
         5 . The aromatic extraction solvent of  claim 1 , wherein the density of the solvent is greater than 1.0 g/cc. 
     
     
         6 . The aromatic extraction solvent of  claim 1 , wherein the density of the solvent is in the range of from 1.1 g/cc to 1.7 g/cc. 
     
     
         7 . The aromatic extraction solvent of  claim 1 , wherein the solvent has an average boiling point greater than 80° C. 
     
     
         8 . The aromatic extraction solvent of  claim 1 , wherein the solvent comprises water in the range of from 0.1 W %-50 W % of the solvent. 
     
     
         9 . The aromatic extraction solvent of  claim 1 , wherein the solvent comprises water in the range of from 1.0 W %-30 W %. 
     
     
         10 . The aromatic extraction solvent of  claim 1 , wherein the solvent is a mixture comprising one or more non-ODSO aromatic extraction solvents. 
     
     
         11 . The aromatic extraction solvent of  claim 10 , wherein the one or more non-ODSO aromatic extraction solvents is selected from the group consisting of diethyleneglycol, triethyleneglycol, tetraethylene glycol, sulfolane, furfural, N-methyl-2-pyrrolidone, N-formylmorpholine and dimethylsulfoxide. 
     
     
         12 . The aromatic extraction solvent of  claim 11 , wherein the one or more non-ODSO aromatic extraction constitutes from 0.1 W %-99.9 W % of the total weight of the solvent mixture. 
     
     
         13 . The aromatic extraction solvent of  claim 1 , wherein the one or more ODSO compounds is selected to remove mono- and poly-aromatic compounds from the hydrocarbon stream. 
     
     
         14 . The aromatic extraction solvent of  claim 1 , wherein the one or more ODSO compounds is selected to remove benzene from the hydrocarbon stream. 
     
     
         15 . The aromatic extraction solvent of  claim 1 , wherein the solvent is liquid at ambient conditions. 
     
     
         16 . The aromatic extraction solvent of  claim 1 , wherein the one or more ODSO compounds are derived from catalytically oxidized disulfide oils present in an effluent refinery hydrocarbon stream recovered downstream of a MEROX process.