Use of Silk Hydrolysate in Chrome Tanning

This study examined the characteristics and environmental load of sheep skins that had been treated with silk hydrolysate by two different methods: prior to tannage and after tannage. Silk hydrolysate was applied to the leathers before and after tanning in four different proportions. The chrome oxide content and shrinkage temperature, tensile strength and tear load of the leathers increased as the proportion of silk hydrolysate increased, and the highest levels of chrome exhaustion in the tanning effluents were obtained at an application level of 5% on the basis of leather weight. In addition, silk hydrolysate was found to improve wastewater parameters such as chemical oxygen demand, total suspended solids, total dissolved solids, salinity and electrical conductivity.