Chemistry and delignification kinetics of Canadian industrial hemp (Cannabis sativa L.)

Strategies to diversify the Canadian fibre supply have provided an impetus for investigating a wide variety of alternative fibres including industrial hemp (Cannabis sativa L.) in Canada. The alkaline delignification kinetics of Canadian hemp (bast, core and whole stem fractions), using micro pulpin g units was investigated. The nature of hemp (macromolecule proportions) wa s a major contributor to the chemical pulping behaviour shown in the result s. The initial lignin and holocellulose content of the bast were 10% and 85 %, respectively, and the core lignin and holocellulose contents were 21% an d 72%, respectively. The bast fibre had a comparative pulping advantage ove r the core fibre region due to its chemical constitution. The activation en ergies for lignin removal from hemp are 41 kJ/mol, 76 kJ/mol and 76 kJ/mol for the bast, core and whole stem respectively. These are considerably lowe r than the reported values for traditional wood pulp species.