Corn fiber for the production of advanced chemicals and materials: derivatizable cellulose and cellulose derivatives made therefrom

Abstract

The invention provides a method of obtaining a cellulose material from corn fiber wherein the method comprises the steps of: (a) heating a mixture of corn fiber and a liquid; (b) contacting the mixture of step (a) with a protease enzyme, thereby providing a proteolyzed corn fiber and a liquid; (c) separating the liquid from the proteolyzed corn fiber; (d) contacting the proteolyzed corn fiber at least once with an alkaline extractant, thereby providing an insoluble cellulose material and a first liquid comprising arabinoxylan; (e) separating the insoluble cellulose material from the first liquid comprising arabinoxylan at a temperature of at or above about 60° C.; and (f) rinsing the insoluble cellulose material to remove essentially all alkali, thereby providing a cellulose material having a cellulose content of at least about 50% and consisting essentially of cellulose I. Cellulose esters and ethers are also prepared from the derivatizable cellulose prepared according to the methods herein.

What is claimed is:  
     
         1 . A method of obtaining a cellulose ester from corn fiber wherein the method comprises the steps of: 
 a. heating a mixture of corn fiber and a liquid;    b. contacting the mixture of step (a) with a protease enzyme, thereby providing a proteolyzed corn fiber and a liquid;    c. separating the liquid from the proteolyzed corn fiber;    d. contacting the proteolyzed corn fiber at least once with an alkaline extractant, thereby providing an insoluble cellulose material and a first liquid comprising arabinoxylan;    e. separating the cellulose material from step (d) from the liquid comprising arabinoxylan at a temperature of at or above about 60° C., thereby providing a cellulose material having a cellulose content of at least about 80% and consisting essentially of cellulose I;    f. optionally subjecting the cellulose material of step (e) to at least one of: a water rinsing step, an additional alkaline extractant contacting step, an alkaline H 2 O 2  bleaching step, a xylanase enzyme contacting step, or an acid rinsing step; and    g. contacting the cellulose material of step (e) or (f) with a C1 to C10 esterifying agent in the presence of a catalyst, thereby providing a cellulose ester.    
     
     
         2 . The method of  claim 1 , wherein the esterifying agent comprises a C1 to C10 acyl anhydride, acyl acid, acyl halide, or a mixture thereof.  
     
     
         3 . The method of  claim 1 , wherein the esterifying agent comprises formic anhydride, acetic anhydride, propionic anhydride, butyric anhydride, or a mixture thereof.  
     
     
         4 . The method of  claim 1 , wherein the cellulose ester comprises cellulose formate, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose formate acetate, cellulose formate propionate, cellulose formate butyrate, cellulose acetate propionate, cellulose acetate butyrate, or a mixture thereof.  
     
     
         5 . The method of  claim 1 , wherein the catalyst comprises H 2 SO 4 , triflouroacetic anhydride, methane sulfonic acid, or a mixture thereof.  
     
     
         6 . The method of  claim 1 , wherein the cellulose ester has a DS/AGU of from about 0.1 to about 3.0.  
     
     
         7 . The method of  claim 1 , wherein the cellulose ester has a DS/AGU of from about 1.7 to about 2.75.  
     
     
         8 . The method of  claim 1 , wherein the cellulose ester has an inherent viscosity of from about 0.001 to about 3.0.  
     
     
         9 . A method of obtaining a cellulose ether from corn fiber wherein the method comprises the steps of: 
 a. heating a mixture of corn fiber and a liquid;    b. contacting the mixture of step (a) with a protease enzyme, thereby providing a proteolyzed corn fiber and a liquid;    c. separating the liquid from the proteolyzed corn fiber;    d. contacting the proteolyzed corn fiber at least once with an alkaline extractant, thereby providing an insoluble cellulose material and a first liquid comprising arabinoxylan;    e. separating the insoluble cellulose material of step (d) from the liquid comprising arabinoxylan at a temperature of at or above about 60° C., thereby providing a cellulose material having a cellulose content of at least about 80% and consisting essentially of cellulose I;    f. optionally subjecting the cellulose material of step (e) to at least one of: a water rinsing step, an additional alkaline extractant contacting step, an alkaline H 2 O 2  bleaching step, a xylanase enzyme contacting step, or an acid rinsing step; and    g. contacting the cellulose material of step (e) or (f) with an O-alkylating agent, thereby providing a cellulose ether.    
     
     
         10 . The method of  claim 9 , wherein the O-alkylating agent comprises alkylene oxide, aryl substituted alkylene oxide, halogen substituted alkylene oxide, alkyl halide, hydroxyalkyl halide, aryl alkyl halide, carboxyalkyl halide, (alkyloxycarbonyl)alkyl halide, allyl halide, vinyl halide, alkyl sulfonate, hydroxyalkyl sulfonate, aryl alkyl sulfonate, carboxyalkyl sulfonate, (alkyloxycarbonyl)alkyl sulfonate, allyl sulfonate, or a mixture thereof.  
     
     
         11 . The method of  claim 9 , wherein the O-alkylating agent comprises ethylene oxide, propylene oxide, butylene oxide, epoxybutene, amylene oxide, glycidol, styrene oxide, epichlorohydrin, methyl chloride, methyl iodide, methyl bromide, ethyl bromide, propyl bromide, butyl bromide, propyl methyl sulfonate, methyl chloroacetic acid, ethyl chloroacetic acid, sodium chloroacetate, chloroacetic acid, benzyl bromide, 1-N,N-dialkylamino-2-chloroethane, or a mixture thereof.  
     
     
         12 . The method of  claim 9 , wherein the O-alkylating agent comprises ethylene oxide, propylene oxide, epoxybutene, methyl chloride, ethyl bromide, sodium chloroacetate, or a mixture thereof.  
     
     
         13 . The method of  claim 9 , wherein the O-alkylating agent is epoxybutene.  
     
     
         14 . The method of  claim 9 , wherein the cellulose ether has a DS/AGU of from about 0.01 to about 3.0.  
     
     
         15 . The method of  claim 9 , wherein the cellulose ether has a DS/AGU of from about 0.3 to about 2.2.  
     
     
         16 . The method of  claim 9 , wherein the cellulose ether has a MS/AGU of from about 0.01 to about 100.  
     
     
         17 . The method of  claim 9 , wherein the cellulose ether has a MS/AGU of from about 0.1 to about 5.