On the use of ZnCl2 together with HCl in lignin determinations

Abstract

As König’s proposal on the use of ZnCl2 together with hydrochloric acid in lignin determinations seems, after Poppoffs experiments, to have been neglected some experiments based on this principle were performed. A mixture of 150 g ZnCl2 and 100 ml concentrated hydrochloric acid appeared to be the most effective for the decomposition of the cell wall carbohydrates. The results obtained were highly comparable to those obtained from the use of 72 per cent H2SO, as hydrolysator. The lignin preparations were lighter in colour than those obtained by the H2SO4 method.