Green process to hydrolyze carbohydrates from tobacco biomass using subcritical water

Abstract

Processes for recovering sugars and nicotine from a tobacco biomass include feeding a biomass of tobacco plants and subcritical water to a reactor, hydrolyzing the biomass of tobacco plants with the subcritical water at a temperature between about 150° C. and 305° C. and recovering a liquid product and a solid product from the reactor, wherein the liquid product contains water-soluble sugars and nicotine.

1 . A process for fractionating carbohydrates and lipids or oils in tobacco plants comprising:
 providing a biomass of tobacco plants mixed with one or more lignocellulosic feedstocks and subcritical water at a first temperature to a reactor;   hydrolyzing the biomass of tobacco plants with the subcritical water at the first temperature of greater than 180° C. and up to about 200° C., wherein the hydrolyzing of the biomass is essentially free of chemicals other than the subcritical water;   recovering a liquid product and a solid product from the reactor, wherein the liquid product contains water-soluble sugars and ranges in pH from 6.2 to 6.9;   recycling the solid product to the reactor with subcritical water at a second temperature;   further hydrolyzing the solid product with the subcritical water at the second temperature of greater than 280° C. and up to about 305° C. wherein the hydrolyzing of the solid product is essentially free of chemicals other than the subcritical water ; and   recovering a second liquid product and a second solid product from the reactor, wherein the second liquid product contains additional water-soluble sugars,   
       wherein hydrolyzing occurs in an absence of cellulose enzymes. 
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . The process of  claim 1  further comprising:
 extracting oil from the solid product. 
 
     
     
         5 . (canceled) 
     
     
         6 . The process of  claim 1  further comprising:
 extracting oil from the second solid product. 
 
     
     
         7 . (canceled) 
     
     
         8 . (canceled) 
     
     
         9 . The process of  claim 1 , wherein the biomass is prepared by wet-grinding the tobacco plants. 
     
     
         10 . A process for fractionating sugars and nicotine from a tobacco biomass comprising:
 feeding a biomass of tobacco plants and subcritical water to a reactor;   performing a single hydrolyzing of the biomass of tobacco plants with the subcritical water at a temperature between about 200° C. and 305° C.; and   recovering a liquid product and a solid product from the reactor, wherein the liquid product contains water soluble sugars and nicotine,   
       wherein the hydrolyzing occurs in an absence of cellulose enzymes. 
     
     
         11 . The process of  claim 10  further comprising:
 extracting oil from the second solid product. 
 
     
     
         12 . The process of  claim 10 , wherein greater than 70 wt % of the solids in the tobacco plants are converted to liquid product. 
     
     
         13 . The process of  claim 10 , wherein hydrolyzing is performed in an acidic environment to optimize nicotine recovery. 
     
     
         14 . The process of  claim 10  having a residence time of between 1 minute and 10 minutes to optimize nicotine recovery. 
     
     
         15 . The process of  claim 10  having a residence time between 5 and 30 seconds to optimize sugar recovery. 
     
     
         16 . (canceled) 
     
     
         17 . The process of  claim 10 , further comprising recovering the nicotine from the liquid product. 
     
     
         18 . The process of  claim 10 , further comprising recycling the water back to a water supply. 
     
     
         19 . The process of  claim 10 , wherein the hydrolyzing of the biomass of tobacco plants with the subcritical water is a continuous process. 
     
     
         20 . The process of  claim 1 , wherein the lignocellulosic feedstock comprises one or a combination of corn stover and switchgrass. 
     
     
         21 . The process of  claim 1 , further comprising recycling the water back to a water supply. 
     
     
         22 . The process of  claim 1 , further comprising recovering a majority of heat from the subcritical water to improve the overall efficiency of the process. 
     
     
         23 . The process of  claim 1 , wherein hydrolyzing the biomass with the subcritical water at the first and second temperatures is a continuous process. 
     
     
         24 . The process of  claim 23 , wherein the continuous process has a residence time of 5 seconds to 15 minutes. 
     
     
         25 . The process of  claim 23 , wherein the continuous process is integrated into a single reactor. 
     
     
         26 . The process of  claim 25 , wherein the reactor is installed at a site of the biomass of tobacco plants. 
     
     
         27 . The process of  claim 25 , wherein the reactor is a tubular reactor.