The effect of treating thermomechanical pulp with Fenton chemistry was evaluated in a model study. Ferrous ions and chelated ferric ions were compared as catalysts while initial pH was varied. The results showed that a catalyst of ferrous sulphate had a greater impact on the pulp (increased total fibre charge and carbonyl groups, more dissolved organic material in filtrate) than ferric ions chelated with EDTA. If using ferric-EDG as catalyst, the hydrogen peroxide consumption was higher and more hydroxyl radicals were detected compared to if using ferrous sulphate. Ferric-EDG, however, gave similar or less effect on the pulp.
Export Date: 7 January 2015