ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The sulfite cooking of viscose cellulose. IV

I. Slávik

Slovak Academy of Sciences, Bratislava

Abstract: cf. C.A. 49, 14319g. The reason for condensation of lignin in sulfite cooking of wood for viscose cellulose is not the low amt. of alkali but the products (I) which come over with the condensate of the relief gas (II) and return into the cooking acid. In the cooking acids from various plants, HCO₂H, AcOH, furfural, terpenes, p-cymene, and thiosulfates, found in II, were detd. Cooking acids contg. these compds. individually and in the mixt. were prepd., and their effect on cellulose was tested. HCO₂H is harmful even in the amts. found in practice. Furfural is less harmful, and its does not accumulate in II. Terpenes are changed little into p-cymene. They are easily emulsified and remain in the cooking acid and are harmful. p-Cymene is sepd. easily. MeOH, EtOH, Me₂CO, and thiosulfates are found in small amts. and are not harmful. To eliminate the harmful effect of I an increase in alkali is not recommended, because it impairs and retards cooking. With a low amt. of alkali the condensation of lignin should be prevented by eliminating the harmful I.

Full paper in Portable Document Format: 910a624.pdf (in Slovak)

Chemical Papers 9 (10) 624–637 (1955)