Tall oil

Tall oil, also called liquid rosin or tallol, is a viscous yellow-black odorous liquid obtained as a by-product of the kraft process of wood pulp manufacture when pulping mainly coniferous trees.^[1][2] The name originated as an anglicization of the Swedish tallolja ('pine oil').^[3] Tall oil is the third largest chemical by-product in a kraft mill after lignin and hemicellulose; the yield of crude tall oil from the process is in the range of 30–50 kg / ton pulp.^[4] It may contribute to 1.0–1.5% of the mill's revenue if not used internally.^{[citation needed]}