Investigation on the application of industrial grade MgO in the alkaline peroxide bleaching of poplar CTMP

Effects of four different kinds of industrial grade MgO as one alkali source in the alkaline peroxide bleaching of poplar chemi-thermomechanical pulp (CTMP) were investigated. The particle size and activity of the MgO played the most important role in the improvement of optical and strength properties of the bleached CTMP. At a 25% substitution percentage of MgO for NaOH, a 77.4% ISO brightness and the optimal tensile index of the bleached CTMP could be obtained. When industrial grade MgO was applied, appropriate increase in Na2SiO3 dosage and pulp consistency could improve the brightness and strength properties of the bleached CTMP.

Effect of industrial grade MgO on bulk of the bleached CTMP.Figure optionsDownload as PowerPoint slide