Process for the selective de-oxygenation of biomass

Abstract

A reactive distillation process is disclosed for the selective oxygenation of a biomass. The biomass may be a ligno-cellulosic biomass, or a bio-oil. The process comprises the steps of contacting a biomass slurry with a particulate inorganic material, and heating the mixture to its boiling point. In a preferred embodiment water vapors emanated from the process are collected and condensed to provide a source of fresh water.

1 . A reactive distillation process for the selective de-oxygenation of a biomass, said process comprising the steps of:
 a) providing a slurry comprising biomass and water;   b) contacting the biomass with a particulate inorganic material;   c) heating the slurry to its boiling point.   
     
     
         2 . The process of  claim 1  wherein the biomass is selected from the group consisting of a bio-oil, a lignocellulosic biomass, or combinations thereof. 
     
     
         3 . The process of  claim 2  wherein step b) comprises exerting mechanical action on the biomass in the presence of the particulate inorganic material. 
     
     
         4 . The process of  claim 3  wherein the mechanical action comprises kneading, milling, crushing, extruding, or a combination thereof. 
     
     
         5 . The process of  claim 1  wherein the inorganic particulate material is an alkaline material selected from Al, Mg, Ca, or a combination thereof. 
     
     
         6 . The process of  claim 1  wherein the slurry of step c) further comprises a soluble alkaline material. 
     
     
         7 . The process of  claim 6  wherein the soluble alkaline material comprises K or Na. 
     
     
         8 . The process of  claim 7  wherein the soluble alkaline material is NaOH or Na 2 CO 3 . 
     
     
         9 . The process of  claim 1  wherein the boiling temperature is less than 250° C. 
     
     
         10 . The process of  claim 1  wherein the slurry of step a) comprises sea water. 
     
     
         11 . The process of  claim 1  wherein water vapor formed in step c) is collected and condensed to fresh water. 
     
     
         12 . The process of  claim 1  wherein step c) produces a water vapor stream, CO 2 , a light gas stream, a gaseous bio-oil stream, a liquid bio-oil stream, and a tar-like slurry. 
     
     
         13 . The process of  claim 1  wherein CO is added to step c) for de-oxygenation of the biomass. 
     
     
         14 . The process of  claim 12  wherein the tar-like slurry is burned to form heat and ash. 
     
     
         15 . The process of  claim 14  wherein at least part of the ash is added to the slurry of step c). 
     
     
         16 . The process of  claim 1  wherein step c) is carried out in a distillation column. 
     
     
         17 . The process of  claim 16  wherein the distillation column contains catalytic packing material. 
     
     
         18 . The process of  claim 1  wherein step c) is carried out at sub-atmospheric pressure. 
     
     
         19 . The process of  claim 11  wherein heat dissipated by the condensing water is used to pre-heat the slurry of step c). 
     
     
         20 . The process of  claim 1  wherein the particulate inorganic material is selected from the group consisting of clay, layered metal hydroxy-oxides, zeolites, aluminas, silica-aluminas, hydrotalcite and hydrotalcite-like materials, and mixtures thereof.