Abstract

Part 1 of this series described preliminary solvent extraction and spectrophotometric rate studies of the co-ordination to trivalent chromium of acetate radical, the acid strength of which approximates closely to that of the acid residues of hide collagen. In the present study, the rate of chrome fixation by hide substance has been deter mined under the same reaction conditions. When hide powder in which the degree of surface development is large, is used as a tannage sub strate, remarkable similarity to acetate co-ordination is observed. In the case of chrome fixation by pelt pieces, evidence of a diffusion limited process is obtained. The experimental observations support the view that carboxyl group co-ordination is the chief mode of chrome fixation in animal hide.