Dissolving Pulp (alpha-cellulose) from Corn Stalk by Kraft Process

Corn stalk can be used as an alternative non-wood raw material to produce cellulosic dissolving grade pulp. In this work, the potential of corn stalk in the production of dissolving pulp (alpha-cellulose) was investigated. It was collected from a corn stalkfarm of Kermanshah, Iran. The sequences of experimental work were: water and acid prehydrolysis at 160°C for 30min, followed by Kraft pulping at 170°C for 90min, and bleached by HEH HEHP sequences. The influence of active alkali (14-20%), and sulphidity (10-25%) on the pulp properties such as yield, kappa number, and degree of polymerization was investigated. In optimum conditions (water prehydrolysis; pulping with active alkali of 20%, sulphidity of 25%; and HEH bleaching sequence), the alpha-cellulose content, degree of polymerization, and ash content of the produced dissolving pulp were acceptable: 94.7%, 269 and 1% respectively. The properties of the produced pulp were comparable with the pulp obtained by other sources. Active alkali was the most important influent parameter, with respect to delignification, whereas the sulphidity had a minor effect.