Utilization of Pinus rigida as Pulpwood for Newsprint Manufacture - Removal of Pitch Substances in Pinus rigida Chips by the Pretreatment of Sulfonation -

신문용지(新聞用紙) 생산용(生産用) 원목(原木)으로의 리기다소나무 이용(利用) - 술폰화(化) 전(前) 처리(處理)에 의한 리기다소나무의 pitch 제거(除去) -

The destructed chips(Pinus rigida Mill) were sulfonated under different conditions and defiberated. The yields and strengths of pulp, fatty acid and resin acid in sulfonated chips were determined. The results of this work were as follows: 1) A sulfonation caused a yield reduction to 97.9~88.2% at single stage. and to 94.9~88.2% at two stage pretreatment. The pulp yields were rapidly draped with increasing cooking temperature from $130^{\circ}C$ to $150^{\circ}C$ 2) Pulp strengths were improved with iacreasing cooking temperature. A sulfonation with 5% $Na_2SO_3$/NaOH(8/2) at single stage and 2% NaOH-5% $Na_2SO_3$ at two stage were most effective and gave the best combination of strength properteis. 3) Fatty acid esters in chips were mostly consisted of palmitic and olleic acid. During a sulfonation the former increased extensively, and the latter was lost with increase of cooking times. The amount of pimaric type in the chips was relatively decreased by the pretreatnent and abietic-type increased. But the changes between two resin acid types were insignificant. 4) The effciency of pitch removal was dependant upon cooking liquor pH. To remove sufficiently the resinous substance, the chips must be sulfonated at over pH 12. Therefore, taking account of pitch removel, two stage sulfonation is considered suitable as reinforcement pulp for newsprint manufacture from pitch pine chips : 2% NaOH($60^{\circ}C$ 1 hr) at first stage and 5% $Na_2SO_3$ ($130^{\circ}C$, 1hr) at secund stage.