STUDIES ON THE DETERMINATION OF PENTOSANS BY ULTRA-VIOLET ABSORPTION SPECTRUM

MULTI-POINTS METHOD (II)

Abstract

The effects of the accessibility of cellulosic materials on the pentosan values are studied.
Colorimetric method with aniline acetate, Smith's method with UV Absorption spectrum and the multi-points method previously suggested by the authors are used for determination of pentosan content of the following six samples; linter pulp, sulphite pulp, viscose rayon and dissolved samples of each in 42% HCl solutions. The following results are obtained experimentally.
1. In the case of colorimetric method and Smith's method, the pentosan value obtained is affected by the accessibility of cellulosic material, especially the latter. Therefore these two methods are applied only to the samples such as pulps, which have low accessibility, are not generally applied to samples such as rayon.
2. Contrary to above, the multi-points method is not affected by the accessibility of samples, but can determine the furfural formed from pentosan selectively. Therefore this method can be applied for the determination of pentosans in cellulosic materials regardless of its accessibility.