1994 Volume 48 Issue 12 Pages 1631-1637
In order to obtain a better understanding of deresinating compounds in Akamatsu (Pinus densiflora) pine wood extractives during kraft pulping, the effects of additives on the deresination of Sugi (Cryptomeria japonica) and Sudajii (Castanopsis cuspidata) wood chips during pulping and washing were investigated. The chemical additives used were as follows : methanol extractives of Akamatsu pine wood, four kind of surfactants (oleic acid, abietic acid, sodium laurylbenzenesulfonate, and polyoxyethylene (20) sorbitan monooleate) as reference compounds.
The solubilization of lipophilic dye (p-dimethyl-aminoazobenzene) by these chemical additives was also examined and the amount of dye solubilized was measured.
Concerning the deresinating compounds in pine wood extractives, the following results were obtained :
(1) There are some deresinating compounds in the methanol extractives of Akamatsu pine wood.
(2) The effectiveness of abietic acid for deresination during pulping was very low.
(3) The ethyl acetate-soluble materials of the methanol extractives of Akamatsu wood were separated into six fractions (fr.1-fr.6). Fraction 5 is neutrals and soluble in 4% NaOH aqueous solution at hexane/4% NaOH extraction. The deresination effectiveness of fr.5 was the highest in the additives studied here.
(4) In the dye solubilization examination, oleic acid was most effective at a solubilization temperature below 80°C.
(5) At 90°C, the amount of dye solubilized by Fraction 5 exceeded that of oleic acid.
(6) Some effective deresinating compounds may exist in Fraction 5 of the methanol extractives from Akamatsu pine wood.
