The Effect of Oxidized White Liquor on Pulp Brightness in Peroxide Bleaching in Pulp Mills

Abstract

This paper aims to study the effect of using Oxidized White Liquor (OWL) on pulp brightness in peroxide bleaching. The proper setting of the concentration of hydrogen peroxide, the bleaching temperature, and the bleaching time was also studied. The Central Composite Design (CCD) was proposed to generate necessary experimental runs. Regression analysis was used to determine the relationship equation. Optimization helped determine that to obtain the targeted brightness of 83%, the ratio between the volume of OWL and sodium hydroxide should be 50:50. This ratio should be used with a concentration of hydrogen peroxide at 6.9 g/kg, a bleaching temperature of 90 oC and a bleaching time of 75 minutes.

Production of Liquid Solar Fuels and Their Use in Fuel Cells

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