Abstract

The rate of uptake by hide of the different chromium complexes present in solutions of three commercial tanning agents (Chromosal B, Chromosal SF and Baychrom A) has been followed using Sephadex gel and cellulose phosphate paper chromatography. Complexes throughout the complete molecular weight and charge distribution range have been shown to bind to the hide and the distribution of complexes in the residual tanning liquor is similar to that in control solutions of the reagents under the same conditions. The residual chromium complexes in the used Chromosal B and Baychrom A liquors have been shown to bind readily to freshly presented pickled hide. These trials have demonstrated the feasibility of re-cycling of chrome-tanning liquors in commercial practice.