Peroxynitrite Mediated Delignification of Pulp: A Comparative Study on the Bleaching Properties of the Carbonate and Hydroxyl Radicals

Abstract

Oxygen delignified pulps were bleached with hydroxyl and carbonate radicals produced from peroxynitrite. The carbonate radical treated pulps showed better selectivity and an increase in brightness. For both radicals, good kappa reductions were obtained. This study shows that the carbonate radical anion is a possible green oxidant for future delignification technologies.

Keywords:

• Peroxynitrite
• Hydroxyl and carbonate radicals
• Delignification
• Kappa, viscosity, and brightness values

Acknowledgments

We gratefully acknowledge financial support from the European Commission, OXYDELIGN project (QLK5‐CT‐1999‐01277) and from the Troëdsson Foundation. We are also grateful for the support from Dr. Sten Ljunggren and Birger Sjögren, STFI, Sweden.