Effect of ClO2, O2 and H2O2 bleaching stages on the formation of chlorophenolic compounds in Jute Cady pulp

Elemental chlorine and chlorine compounds are commonly used in the developing countries for bleaching of pulp. The study deals with the bleaching of Jute Cady pulp with chlorine, chlorine dioxide, peroxide and O₂ treatment and identification of various chlorophenolics compounds. The results show that quantity of the total chlorophenolic compounds formed decreases up to 77% at 100% replacement of chlorine by chlorine dioxide in C stage. A 40% and 79% reduction in COD and color value respectively indicate a significant drop in pollution load. There is a reduction of 52% in total chlorophenolic compound when E stage is changed to Ep. The COD and color values are reduced by 30% and 33% respectively as E stage is changed to Ep stage. Oxygen delignification stage reduced the formation of chlorophenolic compounds by 73%. The effluent COD and the color value is reduced by 45% and 28% respectively during this stage.