Process of conversion of biomass to fuel

Abstract

The present invention is directed to processes for the direct conversion of lipidic biomass fuelstock to combustible fuels. In particular, the invention provides a process for the direct conversion of animal fats to transportations fuels suitable as replacement for petroleum-derived transportation fuels. In one embodiment, the method comprises the steps of hydrolyzing a lipidic biomass to form free fatty acids, catalytically deoxygenating the free fatty acids to form n-alkanes, and reforming at least a portion of the n-alkanes into a mixture of compounds in the correct chain length, conformations, and ratio to be useful transportation fuels. Particularly, the product prepared according to the invention comprises mixtures of hydrocarbon compounds selected from the group consisting of n-alkanes, isoalkanes, aromatics, cycloalkanes, and combinations thereof.

That which is claimed: 
     
         1 . A process for forming a hydrocarbon compound, said process comprising: performing catalytic deoxygenation on a stream comprising a free fatty acid by a decarboxylation reaction pathway to form a product stream comprising a paraffin. 
     
     
         2 . The process according to  claim 1 , wherein said catalytic deoxygenation proceeds via a decarboxylation reaction pathway and a decarbonylation reaction pathway. 
     
     
         3 . The process according to  claim 1 , wherein said catalytic deoxygenation comprises gas-phase deoxygenation. 
     
     
         4 . The process according to  claim 1 , wherein said catalytic deoxygenation comprises the use of a fixed-bed catalyst. 
     
     
         5 . The process according to  claim 1 , wherein said catalytic deoxygenation comprises liquid-phase catalytic deoxygenation carried out in a hydrocarbon solvent. 
     
     
         6 . The process according to  claim 5 , wherein the hydrocarbon solvent comprises a paraffin from the product stream. 
     
     
         7 . The process according to  claim 1 , wherein said catalytic deoxygenation is carried out at a temperature of up to 325° C. 
     
     
         8 . The process according to  claim 1 , wherein said catalytic deoxygenation step comprises the use of a catalyst slurry or catalyst dispersion. 
     
     
         9 . The process according to  claim 1 , wherein said catalytic deoxygenation step does not require the addition of any H 2  to remove the oxygen from the lipidic biomass. 
     
     
         10 . The process according to  claim 1 , wherein said catalytic deoxygenation step further comprises the addition of H 2 . 
     
     
         11 . The process according to  claim 1 , wherein said catalytic deoxygenation is carried out in an atmosphere of about 10% volume or less H 2 . 
     
     
         12 . The process according to  claim 1 , wherein the product stream is substantially oxygenate free. 
     
     
         13 . The process according to  claim 1 , wherein the conversion rate of the free fatty acid to the paraffin is at least about 90%. 
     
     
         14 . The process according to  claim 1 , wherein the conversion rate of the free fatty acid to the paraffin is at least about 98%. 
     
     
         15 . The process according to  claim 1 , wherein the product stream comprises a paraffin having a chain length of eight carbons or greater. 
     
     
         16 . The process according to  claim 1 , wherein the product stream comprises a paraffin having a chain length of 10 to 17 carbon atoms. 
     
     
         17 . The process according to  claim 1 , wherein the product stream comprises a paraffin having a chain length of 15 to 17 carbon atoms. 
     
     
         18 . The process according to  claim 1 , wherein the product stream comprises heptadecane. 
     
     
         19 . The process according to  claim 1 , wherein the product stream comprises a linear paraffin. 
     
     
         20 . The process according to  claim 1 , wherein the paraffin has a carbon number that is one less than the free fatty acid. 
     
     
         21 . The process according to  claim 1 , wherein the free fatty acid has 12 carbon atoms or greater. 
     
     
         22 . The process according to  claim 1 , wherein the free fatty acid has 12 to 18 carbon atoms. 
     
     
         23 . The process according to  claim 1 , wherein the free fatty acid comprises stearic acid, linoleic acid, linolenic acid, palmitic acid, or oleic acid. 
     
     
         24 . The process according to  claim 1 , wherein the process excludes cracking. 
     
     
         25 . The process according to  claim 1 , wherein said deoxygenation is carried out in the presence of a noble metal catalyst. 
     
     
         26 . The process according to  claim 25 , wherein said noble metal catalyst comprises palladium. 
     
     
         27 . The process according to  claim 25 , wherein said catalyst comprises a carbon support. 
     
     
         28 . The process according to  claim 1 , further comprising performing thermal hydrolysis on a lipidic biomass to form the free fatty acid stream. 
     
     
         29 . The process according to  claim 28 , wherein said thermal hydrolysis comprises heating the lipidic biomass in the presence of water to a temperature of about 220° C. to about 300° C. under a pressure sufficient to prevent the water in the reactor from flashing to steam.