BLEACHING OF THERMOMECHANICAL PULP WITH SODIUM PERBORATE

The possibility of using sodium perborate for bleaching thermomechanic al pulp was investigated. The effects of sodium perborate concentratio n, temperature, bleaching time, and pulp consistency, and the influenc e of stabilizing and chelating agents on the final paper brightness we re examined. A comparative study was made on the pulp-bleaching effici encies of sodium perborate and hydrogen peroxide. The experimental dat a indicated that the use of sodium perborate resulted in pulp brightne ss, tensile, tear, and burst strengths almost similar to those of the pulps bleached with hydrogen peroxide.