Removal of Fluorescence from Recycled Fibre Using Chlorine Dioxide, 2000 Recycling Symposium Proceedings
Paul F. Earl, Teresa Znajewski--Chlorine dioxide (ClO2) has long been known as an effective bleaching agent for chemical pulps. Studies have now shown that chlorine dioxide can also be used to remove fluorescence from recycled fibre. Chlorine dioxide reacts with the optical brighteners often added during papermaking, and destroys their fluorescent properties, permanently removing the compounds from the furnish. Chlorine dioxide is also very specific and selective brightness loss is limited to fluorescence loss, and chlorine dioxide will not react with the cellulose. Laboratory studies and mill experiences are reviewed, and a simple, low-capital chlorine dioxide generator is described.
Removal of Fluorescence from Recycled Fibre Using Chlorine Dioxide, 2000 Recycling Symposium Proceed