Sulfite pulping carbohydrate yield

The free sulfur dioxide in the sulfite pulping liquor promotes hydrolysis of the more easily hydrolyzable constituents of wood. A wood such as spruce, which contains 70.1% carbohydrate substances, of which 85.3% are potentially fermentable, gives a 50% yield of a pulp containing 97.7% carbohydrate, of which about 80% is fermentable. The... 

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