Process for the conversion of cellulose in hydrated molten salts

Abstract

A process for converting cellulose to glucose, said process comprising the steps of: providing a hydrated molten salt; contacting the hydrated molten salt with a cellulose-containing material to form dissolved glucose; removing the dissolved glucose from the hydrated molten salt.

1 . A process for converting cellulose to glucose, said process comprising the steps of:
 a) providing a hydrated molten salt;   b) contacting the hydrated molten salt with a cellulose-containing material to form dissolved glucose;   c) removing the dissolved glucose from the hydrated molten salt.   
     
     
         2 . The process of  claim 1  wherein the cellulose-containing material is a cellulosic biomass. 
     
     
         3 . The process of  claim 1  or  2  wherein step c) comprises selectively adsorbing cellulose to Sephadex. 
     
     
         4 . The process of  claim 1  or  2  wherein step c) comprises flushing the hydrated molten salt with a solvent. 
     
     
         5 . The process of  claim 4  wherein the solvent is selected from the group consisting of organic solvents, supercritical fluids, and mixtures thereof. 
     
     
         6 . The process of  claim 1  or  2  wherein the dissolved glucose is removed by conversion to a material that is poorly soluble in the hydrated molten salt. 
     
     
         7 . The process of  claim 6  wherein the glucose is converted to a material comprising an alcohol. 
     
     
         8 . The process of  claim 7  wherein the glucose is converted to a material comprising an alcohol by a process comprising mild hydrogenation. 
     
     
         9 . The process of  claim 7  wherein the glucose is converted to a material comprising an alcohol by a process comprising selective oxidation. 
     
     
         10 . The process of any one of  claims 6 - 9  wherein the conversion is carried out electrochemically. 
     
     
         11 . The process of any one of  claims 6 - 9  wherein the conversion is carried out under the addition of microwave energy. 
     
     
         12 . The process of any one of  claims 6 - 9  wherein the conversion is carried out under the addition of ultrasound energy. 
     
     
         13 . The process of any one of  claims 6 - 9  wherein the conversion is catalyzed in the presence of a catalyst. 
     
     
         14 . The process of  claim 13  wherein the catalyst is a particulate solid material that is dispersed in the hydrated molten salt. 
     
     
         15 . The process of any one of  claims 7 - 14  comprising the further step of hydrogenating the alcohol to form an alkane. 
     
     
         16 . The process of  claim 15  wherein the alcohol is separated from the hydrated molten salt prior to conversion to the alkane. 
     
     
         17 . The process of  claim 2  wherein the cellulosic biomass is substantially lignin-free. 
     
     
         18 . The process of  claim 17  wherein the substantially lignin-free biomass is prepared by mild hydrothermal treatment of lignin-containing biomass. 
     
     
         19 . The process of any of  claims 6 - 18  wherein the conversion comprises a reaction is a micro channel reactor. 
     
     
         20 . The process of  claim 19  wherein the micro channel reactor is at least partially coated with a catalytic material. 
     
     
         21 . The process of  claim 15  or  16  wherein hydrogen used in the hydrogenation reaction is generated by reforming cellulosic biomass. 
     
     
         22 . The process of  claim 15  or  16  wherein hydrogen used in the hydrogenation reaction is generated by reforming lignin. 
     
     
         23 . A process for selectively dissolving cellulose, said process comprising the steps of:
 a. Providing a source of lignocellulosic material;   b. Contacting the lignocellulosic material with a molten salt under reaction conditions that minimize the depolymerization of cellulose.   
     
     
         24 . The process of  claim 23  wherein the lignocellulosic material further comprises hemicellulose. 
     
     
         25 . The process of  claim 24  wherein the lignocellulosic material is a lignocellulosic biomass material. 
     
     
         26 . The process of any one of the preceding claims wherein the hydrated molten salt is hydrated zinc chloride. 
     
     
         27 . The process of any one of  claims 23 - 26  wherein the reaction conditions comprise a temperature of from 40 to 80° C. 
     
     
         28 . The process of  claim 27  wherein the reaction conditions comprise the substantial absence of mineral acid. 
     
     
         29 . The process of any one of  claims 23 - 28  whereby water is removed from the molten salt during step b). 
     
     
         30 . The process of  claim 29  whereby step b) is carried out under reduced pressure. 
     
     
         31 . The process of  claim 30  whereby step b) is carried out at a pressure which is at or near the saturated steam pressure of the reaction temperature. 
     
     
         32 . The process of  claim 31  whereby step b) is carried out at a temperature in the range of 60 to 70° C. and a pressure in the range of 0.20 to 0.30 bar. 
     
     
         33 . The process of any one of  claims 23 - 32  whereby lignin is removed from the molten salt during or after step b). 
     
     
         34 . The process of any one of  claims 24 - 33  whereby hemicellulose is converted to a reaction product comprising an alcohol. 
     
     
         35 . The process of  claim 34  wherein the reaction product comprises xylotol. 
     
     
         36 . The process of any one of  claims 23 - 35  wherein the solution obtained in step b) is extruded into a coagulating medium. 
     
     
         37 . The process of  claim 36  wherein the coagulating medium is selected from the group consisting of the C 1  to C 8  alcohols, the C 1  to C 8  ketones, and mixtures thereof. 
     
     
         38 . The process of  claim 36  or  37  wherein the cellulose is extruded in the form of fibers. 
     
     
         39 . The process of  claim 38  wherein the cellulose fibers are subjected a post-treatment step for increasing the crystallinity of the cellulose. 
     
     
         40 . The process of  claim 39  wherein the post-treatment step comprises stretching.