Acetic acid from wood-pulping liquors

Refining of Sugar and Recovery of Acetic Acid from Wood-Pulping Liquors... 

The production of wood pulp from lignocellulosic materials by treatment with various chemical liquors, particularly the neutral sulfite semichemical process and the kraft or sulfate process, gives residual black liquors. These contain salts that carry acetic acid and formic acid equivalent to 5% or more of the dry weight of the wood. 

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