Modification of Loblolly Pine Chips with Ceriporiopsis subvermispora Part 2: Kraft Pulping of Treated Chips

Abstract

Loblolly pine (Pinus taeda) chips treated with Ceriporiopsis subvermispora for two or four weeks were pulped with different combinations of kraft pulping conditions to obtain a better understanding of the interaction between the fungal action and the pulping variables. Two different levels of effective alkali (18 or 22%), two times at maximum T_max (60 or 90 min), 22% sulfidity, and a T_max of 170°C, were used. The best delignification without adversely affecting pulp viscosity was found in pulps made from chips treated with the fungus for 2 weeks and at the mildest pulping conditions. At all pulping conditions there was a substantial decrease in the amount of rejects with 2 weeks of fungal treatment. Pulps from fungally‐treated chips refined more easily than the control pulp and strength properties of pulps of fungally‐treated chips were superior to those of the control pulp.

Keywords:

• Ceriporiopsis subvermispora
• white‐rot fungus
• loblolly pine
• kraft pulping
• kappa number
• lignin
• carbohydrates
• viscosity
• refining
• strength properties