Wood saccharification concentrated-acid processes

Bergius-Willstatter saccharification process. Process for industrial production of fermentable sugar from wood by hydrolysis of tannin and xylan-free cellulose with 40-45% hydrochloric acid. The use of concentrated acid requires acid-resistant equipment and recovery of acid. The sugar produced must be rehydrolyzed prior to fermentation. 

Cellulose an unbranched plant polysaccharide, M, 300,000-500,000, consisting of pi,4-linked glucose units. C. is enzymatically hydrolysed to the disaccharide cellobiose. It can be hydrolysed to D-glucose by treatment with concentrated acids, such as 40% HCl or 60-70 % H2SO4 at high temperature. This process, called saccharification of wood, is used to produce fermentable sugar from wood. 

Bergius-Rheinau A saccharification process in which wood is hydrolyzed with concentrated hydrochloric acid to produce sugars for subsequent fermentation to ethanol. 

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