Production of Ester-Based Fuels Such As Biodiesel From Renewable Starting Materials

Abstract

Production of ester-based fuels such as biodiesel or jet fuel from renewable starting materials such as lignocellulosic material or algae is disclosed. Pulping and saccharification of the renewable starting materials produces carboxylic acids such as fatty acids or rosin acids, which are esterified via a gas sparged, slurry form of heterogeneous reactive distillation to yield ester-based fuels.

1 . A process for the production of biodiesel from a concentration of algae, the process comprising:
 i) comminution of the concentration;   ii) production of an organic layer comprising fatty acid soaps;   iii) acidulation of the organic layer to produce free fatty acids;   iv) heterogeneous esterification of the fatty acids with alcohol to produce an ester; and   v) refining of the resulting ester to produce an ester-based fuel.   
     
     
         2 . The process according to  claim 1 , wherein, following production of the organic layer, any residual material is further processed in fermentation and purification steps to yield ethanol. 
     
     
         3 . The process according to  claim 2 , wherein the ethanol produced from the residual material makes up a substantial amount of the alcohol of step iv. 
     
     
         4 . The process of  claim 3 , wherein the alcohol is a C1-C8 alcohol. 
     
     
         5 . The process of  claim 1 , wherein said comminution comprises solid or liquid shearing. 
     
     
         6 . The process of  claim 1 , wherein said organic layer is produced via alkali lysing of the concentration. 
     
     
         7 . The process of  claim 1 , wherein the organic layer comprises from about 30-40% fatty acid soaps. 
     
     
         8 . The process according to  claim 1 , wherein said esterification occurs via a gas sparged, slurry form of heterogeneous reactive distillation in a reaction chamber. 
     
     
         9 . The process according to  claim 8 , wherein the gas sparged, slurry form of heterogeneous reactive distillation includes free particulate acidic ion exchange resin catalysts to catalyze esterification. 
     
     
         10 . The process according to  claim 10 , wherein the reaction chamber comprises a vertical column reactor provided with a plurality of esterification trays mounted one above another, wherein the esterification trays are adapted to allow liquid phase to pass down the column reactor and vapor phase to pass up the column reactor. 
     
     
         11 . The process according to  claim 10 , wherein the reaction chamber comprises a vertical column reactor provided with structured packing wherein the packing is adapted to support catalyst at one or more points in the reactor and to allow liquid phase to pass down and vapor phase to pass up the column reactor.