Methods of refining natural oils, and methods of producing fuel compositions

Abstract

A method for suppressing dehydrogenation includes reacting an optionally functionalized olefin reactant in a metathesis reaction to form an olefin metathesis product; and providing a dehydrogenation suppression agent in admixture with (a) the olefin metathesis product and/or the optionally functionalized olefin reactant, and (b) a metal-containing material selected from the group consisting of residual metathesis catalyst, a hydrogen transfer agent, and a combination thereof, under conditions that are sufficient to passivate at least a portion of the metal-containing material. Methods of refining natural oils and methods of producing fuel compositions are also described.

1 . A method of refining a natural oil comprising:
 providing a feedstock comprising a natural oil;   reacting the feedstock in the presence of a metathesis catalyst to form a metathesized product comprising olefins and esters;   providing a dehydrogenation suppression agent in admixture with the feedstock and/or the metathesized product;   passivating a metal-containing material with the dehydrogenation suppression agent;   separating the olefins in the metathesized product from the esters in the metathesized product; and   transesterifying the esters in the presence of an alcohol to form a transesterified product and/or hydrogenating the olefins to form a fully or partially saturated hydrogenated product;
 wherein the metal-containing material comprises residual metathesis catalyst, a hydrogen transfer agent, or a combination thereof; and 
 wherein non-passivated metal-containing material is configured to participate in, catalyze, promote, and/or facilitate dehydrogenation of the natural oil and/or the metathesized product. 
   
     
     
         2 . The invention of  claim 1  wherein the natural oil and/or the metathesized product comprises one or a plurality of substructures having a formula —CH═CH—CH 2 —CH═CH—. 
     
     
         3 . The invention of  claim 1  wherein the natural oil is selected from the group consisting of canola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, high oleic sunflower oil, linseed oil, palm kernel oil, tung oil, jatropha oil, mustard oil, camelina oil, pennycress oil, hemp oil, algal oil, castor oil, lard, tallow, poultry fat, yellow grease, fish oil, tall oils, and combinations thereof 
     
     
         4 . The invention of  claim 1  wherein the natural oil comprises a polyunsaturated fatty acid and/or a derivative thereof. 
     
     
         5 . The invention of  claim 1  wherein the reacting comprises self-metathesis of the natural oil. 
     
     
         6 . The invention of  claim 1  further comprising providing a low-molecular weight olefin, wherein the reacting comprises cross-metathesis between the natural oil and the low-molecular weight olefin. 
     
     
         7 . The invention of  claim 1  wherein the dehydrogenation suppression agent suppresses isomerization and dehydrogenation of the metathesized product. 
     
     
         8 . The invention of  claim 1  wherein the hydrogen transfer agent comprises a hydrogenation catalyst. 
     
     
         9 . The invention of  claim 1  wherein the dehydrogenation suppression agent comprises a hydrogen transfer inhibitor. 
     
     
         10 . The invention of  claim 1  wherein the dehydrogenation suppression agent comprises phosphorous. 
     
     
         11 . The invention of  claim 10  wherein the dehydrogenation suppression agent is a material selected from the group consisting of PH 3 , a phosphine, a phosphonium salt, a phosphine oxide, a phosphorous oxo acid, a salt of a phosphorous oxo acid, an ester of a phosphorous oxo acid, a derivative of a phosphorous oxo acid in which at least one P—H bond has been replaced by a P—C bond, a salt of the derivative, an ester of the derivative, and combinations thereof. 
     
     
         12 . The invention of  claim 11  wherein the phosphine comprises a structure P(R 1 )(R 2 )(R 3 ), wherein R 1 , R 2 , and R 3  are alike or different and are each independently selected from the group consisting of hydrogen, substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein two of R 1 , R 2 , and R 3  taken together may optionally form a ring with phosphorous; and wherein covalent bonds may optionally exist between two or more of R 1 , R 2 , and R 3 . 
     
     
         13 . The invention of  claim 11  wherein the phosphonium salt comprises a structure selected from the group consisting of [ + P(R 1 )(R 2 )(R 3 )(R 4 )]X − , [ + P(R 1 )(R 2 )(R 3 )(R 4 ) 2 X 2− , and a combination thereof, wherein R 1 , R 2 , R 3 , and R 4  are alike or different and are each independently selected from the group consisting of hydrogen, substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein X represents an anion; wherein two of R 1 , R 2 , R 3 , and R 4  taken together may optionally form a ring with phosphorous; and wherein covalent bonds may optionally exist between two or more of R 1 , R 2 , R 3 , and R 4 . 
     
     
         14 . The invention of  claim 11  wherein the ester of the derivative comprises a structure selected from the group consisting of R 1 HP(O)OR 2 , R 3 R 4 P(O)OR 5 , and a combination thereof; wherein R 1 , R 2 , R 3 , R 4 , and R 5  are alike or different and are each independently selected from the group consisting of substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein R 1  and OR 2  taken together may optionally form a bond with phosphorous; wherein a covalent bond may optionally exist between R 1  and R 2 ; wherein two of R 3 , R 4 , and OR 5  taken together may optionally form a ring with phosphorous; and wherein covalent bonds may optionally exist between two or more of R 3 , R 4 , and R 5 . 
     
     
         15 . The invention of  claim 10  wherein the dehydrogenation suppression agent comprising phosphorous is selected from the group consisting of phosphoric acid, phosphorous acid, phosphinic acid, phosphonic acid, phosphinic acid, phosphinous acid, and combinations thereof. 
     
     
         16 . The invention of  claim 10  wherein the dehydrogenation suppression agent comprises phosphorous acid, which is provided in an aqueous solution having a concentration of between about 0.1 wt % and about 70 wt %. 
     
     
         17 . The invention of  claim 10  wherein the dehydrogenation suppression agent comprises phosphinic acid, which is provided in an aqueous solution having a concentration of between about 0.1 wt % and about 50 wt %. 
     
     
         18 . The invention of  claim 10  wherein the dehydrogenation suppression agent comprises a phosphite ester having a structure P(OR 1 )(OR 2 )(OR 3 ), wherein R 1 , R 2 , and R 3  are alike or different and are each independently selected from the group consisting of substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein two of OR 1 , OR 2 , and OR 3  taken together may optionally form a ring with phosphorous; and wherein covalent bonds may optionally exist between two or more of R 1 , R 2 , and R 3 . 
     
     
         19 . The invention of  claim 1  wherein the dehydrogenation suppression agent comprises nitrogen. 
     
     
         20 . The invention of  claim 19  wherein the dehydrogenation suppression agent is a material selected from the group consisting of ammonia, primary amines, secondary amines, tertiary amines, ammonium salts, polyamines, nitric acid, and combinations thereof. 
     
     
         21 . The invention of  claim 20  wherein the primary amines are selected from the group consisting of optionally functionalized alkyl amines, optionally functionalized aryl amines, and combinations thereof; wherein the secondary amines and tertiary amines are each independently selected from the group consisting of optionally functionalized alkyl amines, optionally functionalized aryl amines, optionally functionalized mixed alkyl-aryl amines, and combinations thereof; and wherein the ammonium salts comprise ammonium cations selected from the group consisting of optionally functionalized tetraalkylammoniums, optionally functionalized tetraarylammoniums, optionally functionalized mixed alkyl-aryl ammoniums, and combinations thereof. 
     
     
         22 . The invention of  claim 20  wherein the primary amines comprise a structure having a formula NH 2 R, wherein R is selected from the group consisting of substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof. 
     
     
         23 . The invention of  claim 20  wherein the secondary amines comprise a structure having a formula NHR 1 R 2 , wherein R 1  and R 2  are alike or different and are each independently selected from the group consisting of substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein R 1  and R 2  taken together may optionally form a ring with nitrogen; and wherein covalent bonds may optionally exist between R 1  and R 2 . 
     
     
         24 . The invention of  claim 20  wherein the tertiary amines comprise a structure having a formula NR 1 R 2 R 3 , wherein R 1 , R 2 , and R 3  are alike or different and are each independently selected from the group consisting of substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein two of R 1 , R 2 , and R 3  taken together may optionally form a ring with nitrogen; and wherein covalent bonds may optionally exist between two or more of R 1 , R 2 , and R 3 . 
     
     
         25 . The invention of  claim 20  wherein the ammonium salts comprise a structure selected from the group consisting of [ + N(R 1 )(R 2 )(R 3 )(R 4 )]X − , [ + N(R 1 )(R 2 )(R 3 )(R 4 )] 2 X 2− , and a combination thereof, wherein R 1 , R 2 , R 3 , and R 4  are alike or different and are each independently selected from the group consisting of hydrogen, substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; wherein X represents an anion; wherein two of R 1 , R 2 , R 3 , and R 4  taken together may optionally form a ring with nitrogen; and wherein covalent bonds may optionally exist between two or more of R 1 , R 2 , R 3 , and R 4 . 
     
     
         26 . The invention of  claim 20  wherein the polyamines comprise a structure R 6 R 7 N-L-NR 8 R 9 , wherein R 6 , R 7 , R 8 , and R 9  are alike or different and are each independently selected from the group consisting of hydrogen, substituted or unsubstituted optionally functionalized C 1 -C 100  alkyl, substituted or unsubstituted optionally functionalized aryl, and combinations thereof; and wherein L is a linker selected from the group consisting of (i) substituted or unsubstituted, optionally functionalized aryl groups, (ii) cyclic or acyclic, substituted or unsubstituted, optionally functionalized alkyl groups, and (iii) combinations thereof. 
     
     
         27 . The invention of  claim 20  wherein the nitric acid is selected from the group consisting of anhydrous nitric acid, fuming nitric acid, concentrated nitric acid, solid hydrates of nitric acid, solutions of nitric acid, and combinations thereof. 
     
     
         28 . The invention of  claim 1  wherein the dehydrogenation suppression agent comprises a quinone, a hydroquinone, or a combination thereof. 
     
     
         29 . The invention of  claim 28  wherein the quinone is an electron-deficient quinone. 
     
     
         30 . The invention of  claim 28  wherein the quinone is selected from the group consisting of optionally functionalized benzoquinones, optionally functionalized naphthoquinones, optionally functionalized anthraquinones, and combinations thereof. 
     
     
         31 . The invention of  claim 28  wherein the quinone is selected from the group consisting of 1,2-benzoquinone, 1,4-benzoquinone, tetrachloro-p-benzoquinone, 2-chloro-1,4-benzoquinone, 2,6-dichloro-1,4-benzoquinone, difluoro-1,4-benzoquinone, trifluoro-1,4-benzoquinone, tetrafluoro-1,4-benzoquinone, 2,5-dichlorobenzoquinone, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, 1,2-naphthoquinone, 1,4-naphthoquinone, 2,6-naphthoquinone, 9,10-anthraquinone, 2-hydroxy-1,4-naphthoquinone, 2-chloro-1,4-naphthoquinone, 2,3-dichloro-1,4-naphthoquinone, 2-bromo-1,4-naphthoquinone, 2,3-dibromo-1,4-naphthoquinone, plastoquinone, phylloquinone, ubiquinone, 2,3-dihydroxy-9,10-anthraquinone, 2,6-dichloro-1,4-benzoquinone, tetrachloro-1,4-benzoquinone, 2,6-dimethoxy-1,4-benzoquinone, 2,6-di-tert-butyl-1,4-benzoquinone, and combinations thereof.