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U.S. Department of Energy
Office of Scientific and Technical Information

Increasing the digestibility of cellulosic material using nitric acid

Patent ·
OSTI ID:5718916
The digestibility of sawdust, rice hulls, bagasse straw, and other plant materials is increased by cooking with HNO/sub 3/ and a nonoxidizing acid at 150 psig for 30 to 60 min. Thus, oak sawdust is mixed with 9 ml HNO/sub 3/ and 0.2 g Fe/lb. and water to provide a mixture with 20 to 50% water. This mixture is autoclaved at 100 to 125 psig for approximately 45 min. The product may be neutralized with NH/sub 3/ or other nontoxic base. Hickory and other woods with a low acidity require the addition of a nonoxidizing acid; H/sub 3/PO/sub 4/ is especially preferred. The crude fiber and N-free extract concentration in the oak sawdust before and after treatment are 55.2 and 31.76% and 27.4 and 65.03% respectively.
Assignee:
TIC; EDB-80-004477
Patent Number(s):
US 4053645
OSTI ID:
5718916
Country of Publication:
United States
Language:
English