Abstract
The effects of five chemical additives on the deresination of aspen wood during kraft pulping and washing were investigated. Without additives, only about half of the potentially saponifiable wood resin was saponified in the digester. For deresination during pulping and washing, the additives could be ranked according to their effectiveness as follows: distilled tall oil > Canadian tall oil (acid No. 131) > gum rosin > abietic acid, at charges of 1 to 3% on OD wood. A commercial surfactant formulation was found not to be cost effective.