Systems and methods for producing biofuels and related materials

Abstract

Clostridium phytofermentans cells (American Type Culture Collection 700394 T ) and all other strains of the species can ferment materials such as biomass into useful products and coproducts, such as ethanol, hydrogen and organic acids. Compositions that include Clostridium phytofermentans are also disclosed.

19 . A method of making a fuel, the method comprising:
 a. combining  Clostridium phytofermentans  cells and a material comprising a carbohydrate in a medium, wherein a concentration of the carbohydrate in the medium is greater than 40 mM; and   b. fermenting the material comprising the carbohydrate under conditions and for a time sufficient to produce a fuel.   
   
   
       20 . The method of  claim 19 , wherein the concentration is greater than 50 mM. 
   
   
       21 . The method of  claim 20 , wherein the concentration is greater than 100 mM. 
   
   
       22 . The method of  claim 21 , wherein the concentration is less than 2000 mM. 
   
   
       23 . The method of  claim 19 , wherein the material comprises a low molecular weight carbohydrate having a molecular weight of less than 1,000. 
   
   
       24 . The method of  claim 23 , wherein the low molecular weight carbohydrate is selected from the group consisting of arabinose, cellobiose, fructose, galactose, glucose, lactose, mannose, ribose, xylose, and mixtures thereof. 
   
   
       25 . The method of  claim 19 , wherein the material comprises a high molecular weight carbohydrate having a molecular weight of greater than 1,000. 
   
   
       26 . The method of  claim 25 , wherein the high molecular weight carbohydrate is selected from the group consisting of cellulose, microcrystalline cellulose, polygalacturonic acid, pectin, starch, xylan, and mixtures thereof. 
   
   
       27 . The method of  claim 19 , wherein the material is pulverized such that it has a particle size of between about 5 microns and 50 microns. 
   
   
       28 . The method of  claim 19 , wherein the material comprises a blend of two or more carbohydrates. 
   
   
       29 . The method of  claim 19 , wherein the material comprises a cellulosic or lignocellulosic material. 
   
   
       30 . The method of  claim 29 , wherein the cellulosic or lignocellulosic material is selected from the group consisting of polycoated paper, Kraft paper, papermaking sludge, wood, wood pulp, distillers grains, particle board, leaves, grasses, grass clippings, rice hulls, bagasse, cotton, jute, hemp, flax, bamboo, sisal, abaca, straw, corn cobs, corn stover, wheat straw, coconut hair, algae, switchgrass,  crambe , biomass crops, and mixtures thereof. 
   
   
       31 . The method of  claim 19 , wherein the material comprises a low molecular weight carbohydrate formed by breaking down a high molecular weight carbohydrate. 
   
   
       32 . The method of  claim 31 , wherein the breaking down includes using an enzyme. 
   
   
       33 . The method of  claim 32 , wherein the enzyme is selected from the group consisting of endoglucanases, exoglucanases, cellobiohydrolases (CBH), β-glucosidase, glycoside hydrolases, glycosyltransferases, lyases, and esterases active against components of hemicellulose, pectin, and starch, and mixtures thereof. 
   
   
       34 . The method of  claim 19 , wherein the material is substantially free of lignin.