Title
Application of magnetically recyclable ZSM-5 zeolite for enhancement of peroxide bleaching of thermal-mechanical pulp
Authors
PHAN HUY HOANG and NGUYEN VIET LONG

Received October 1, 2015
Published Volume 51 Issue 5-6 May-June
Keywords adsorption, ISO brightness, magnetic separation, peroxide bleaching, ZSM-5 zeolite

Abstract
A new efficient magnetically recyclable ZSM-5 zeolite (MZZ) has been successfully applied for alkaline peroxide bleaching of TMP pulp of Acacia mangium to enhance the bleaching process. The zeolite particles exhibited high efficiency in adsorbing transition metal ions (manganese, copper etc.) that could lead to decomposition of hydrogen peroxide during the bleaching process. These particles also increased the brightness of pulp after bleaching. Furthermore, the optimum conditions for peroxide bleaching of TMP pulp, such as hydrogen peroxide dosage, MZZ particle charge and temperature, were determined through a series of experiments. By applying an appropriate external magnetic field, the MZZ particles were separated easily without agglomeration and then reused efficiently with no significant loss of metal adsorption capacity. The performance of the developed MZZ particles would make their application in peroxide bleaching efficient, economical and feasible. Moreover, the use of zeolite would not cause any operational issues and would not influence the quality of pulp and paper products, due to this convenient separation.