Improving Hydrogen Peroxide Bleaching of PRC-APMP by Using Urea

Abstract

Preconditioning Refiner Chemic Alkaline Peroxide Mechanical Pulp (PRC-APMP) is one of the most currently used high yield pulps in China. During the bleaching of PRC-APMP, hydrogen peroxide is a commonly used bleaching agent. In order to improve the bleaching efficiency of PRC-APMP, urea was used as an activator in peroxide bleaching of aspen PRC-APMP. The results showed that the brightness of the urea-based bleached pulp higher than that without urea addition at the same hydrogen peroxide dosage. The physical properties such as the breaking length, tear index and fiber length of the bleached pulp were comparable to those without urea addition in peroxide bleaching.