The effect of AQ and NaBH4 on bio-kraft delignification (Ceriporiopsis subvermispora) of brutia pine chips

Brutia pine wood chips were pretreated with lignin degrading fungus (Ceriporiopsis subvermispora) and its effects on kraft pulping involved adding antraquinone (AQ) and NaBH4 into the white liquor were studied. The results showed that pulp rejects were lower for biokraft pulp and a significant reduction was observed when biokraft process was modified by NaBH4 compared to the control kraft method. Also, an increase on pulp yield and reduction on kappa number was noticed with biokraft pulp. Adding AQ and NaBH4 into biopulping led to positive results with regards to pulp yield and kappa number compared to biokraft pulp. The results indicated a major increase in pulp brightness when biokraft pulping was modified with 2% NaBH4. On the other hand, biopulps gave lower tear but higher burst index compared to the control kraft pulp. Tensile index of the biopulps were slightly lower; however, untreated kraft pulp was found to be easier to refine and when pulps were refined to 12,000 revs. in PFI mill, biokraft-AQ pulp showed a significant improvement on tensile index.