The pulping stage of paper production is the process of breaking down the bulk structure of the fibre source into the constituent fibers by chemical, mechanical or both means. Magnesium oxide is used in chemical pulping when the sulfite process is followed. Magnesium oxide can potentially find use also in the most widely used Kraft pulping Process.
The bleaching stage of the Pulp aims in increasing the brightness of the paper produced by modifying the color of the lignin in the pulp. Magnesium oxide can be used in oxygen and hydorgen peroxide bleaching processes in replacement of caustic soda as an alkali and magnesium sulfate as a cellulose protector/peroxide stabilizer with technical and financial benefits.
An additional application of magnesium oxide in the paper and pulp industry is found in the wastewater treatment that paper and pulping mills should use for the disposal of their water.
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