| Summary: The aim of this study is to increase the limited performance of the lignin removal of the oxygen delignification method that applied before the bleaching. For this purpose, primarily, cherry balsam that has a radical scavenger characteristic is added into the delignification medium with the aim of preventing the loss of pulp’s viscosity caused by harmful oxidation reactions in an alkaline medium between oxygen and polysaccharide fraction of the pulp. Secondarily, a more intensive oxidative medium is established thereby adding peroxide into oxygen delignification solution to solve additional lignin. The pulp specimens that used in this study is made by the method of kraft. In terms of oxygen delignification method the most suitable alkaline ratio is determined as %3. In comparison with the conventional oxygen delignification method, addition of only 2% cherry gum into the reaction medium occurred to %2.1 delignification and 1.9%viscosity improvements. The delignification degree of %54.8 in conventional method can be increased to %60.7 by adding %1 peroxide into reaction medium. As a result of modification in conventional oxygen delignification method with addition of cherry gum and peroxide, the most light-colored pulps are obtained. But the combination of cherry gum and peroxide doesn’t lead to any statistical significant losses on breaking length, bursting and tearing indexes.
Key Words: Kraft pulp, Oxygen Delignification, Cherry Balsam, Selectivity
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