Application of Alkaline Ionic Liquids in the Pretreatment Process of Eucalyptus Kraft Pulping

Abstract

In order to explore the potential application of green solvent ionic liquids (ILs) in the kraft pulping process, eucalyptus wood was pretreated by [Mmim]DMP before normal pulping. The results showed that materials pretreated shortly by the ionic liquid had a higher yield and viscosity coupled with a lower potassium permanganate value and residual lignin content in the pulp, as a result of the cooking process. It was also inferred that alkaline [Mmim]DMP pretreatment could dissolve lignin effectively from fiber to result in a stronger binding force and more entangled properties. Paper tensile and burst strength were improved by about 40% and 60%, respectively. These results provide a new way for eucalyptus to be utilized in the kraft pulping process.