未晒亜硫酸パルプアルカリ精製に關する研究 第一報
1950 年 4 巻 6 号 p. 9-16
詳細
1950 年 4 巻 6 号 p. 9-16
Hot alkali refining process of sulfite pulp was studied. 20 gms. of chlorinated pulp was refined in the caustic soda solutions at the consistency of 5%, with varying quantities of NaOH (4, 5, 6% against pulp) at varying temperatures (80°, 85°, 90°, 95° and 100°C) and for varying times (2 and 4 hrs) respectively. The waste liquor was subjected to potentiometric and conductometric titrations with normal solutions of HCl and NaOH. From analytical results the distribution of the original caustic soda was estimated, i. e., the combined alkali with weak acidic organic substance in the liquor, free hydroxyde in the liquor and the alkali retained in the residual fibre. Free organic acid was also estimated, when the amount of soda was insufficient. The organic matter involved three kinds of organic acid whose dissociation constants were in the orders of 10-4, 10-8 and 10-10 respectively.
The amount of organic matters dissolved in the waste liquor was also estimated and the ratio with combined Na was calculated. The ratio was approximately 4.5 and the mean equivalent weight of orgainc matters was concluded to be 100 - 130.
