Production of dissolving pulp (alpha-cellulose) from wastes of corn stalk

Non-wood fibres are increasingly being used in the pulp and paper industry to help meet the increasing world demand for paper and also to reduce demand on declining forest reserves. In this work, the dissolving pulp (alpha-cellulose) was produced from corn stalk of the agricultural farms of Kermanshah-Iran. The sequences of experimental work were: water and acid prehydrolysis for 30min at 160°C, then a Kraft pulping for 90min at 170°C, followed by a HEH & HEHP bleaching process. The influence of two parameters: active alkali (14-20%), and sulphidity (10, 25%) on the pulp properties (yield, kappa number, and degree of polymerization), was investigated. In optimum conditions (water prehydrolysis, pulping with 10% sulphidity, and HEH bleaching sequences), the alpha-cellulose content, degree of polymerization, and ash content of the produced dissolving pulp were: 94.1%, 378.1 and 2% respectively. With respect to delignification, active alkali was the most important influent parameter whereas the sulphidity had a minor effect.

Keywords:

Kraft process , corn stalk , dissolving pulp , alpha-cellulose , pre-hydrolysis , wastes