Chlorine Dioxide for Decolorizing Deinked Mixed Office Waste, 1995 Recycling Symposium Proceedings
Philip E. Quinnett
L. René Ward
Technology Center Olin Chlor-Alkali Products
In the future, waste paper quality is expected to diminish and cost is projected to increase. As a result, decolorizing agents that are effective on highly colored wastes are of increasing value to recycled paper processors, especially those producing white paper products. This paper summarizes laboratory evaluation tests using C1O2 as the primary decolorizing agent on a highly colored, commercially deinked pulp. A general laboratory optimization was performed. The results indicate a brightness increase of greater than 30 points and 90% decolorization is possible with a single ClO2 stage. The use of a two-stage process with sodium hydrosulfite reduced the chlorine dioxide requirements and helped adjust color shade to minimize yellowness. These results demonstrate that ClO2 is a highly effective decolorizing agent for this Mixed Office Waste furnish.
Chlorine Dioxide for Decolorizing Deinked Mixed Office Waste, 1995 Recycling Symposium Proceedings