Total Elimination of Polluting Chrome Shavings, Chrome, and Dye Exhaust Liquors of Tannery by a Method Using Keratin Hydrolysate

Abstract

The solid and liquid waste management of tanneries has become a serious problem in the leather industry. In this study, we have attempted and succeeded in eliminating these pollutants by a novel method that has not been done anywhere so far. Keratin hydrolysate (KH) from poultry feathers has been utilized along with chrome shavings (CS) for total elimination of the polluting solid and liquid wastes in a tannery. In this process, 100% fixation of the Cr from the chrome exhaust liquor and the dye from the dye exhaust liquor is achieved by the reactions of CS with KH. The infrared spectra of the different stages of CS confirm the fixation of Cr in the chrome shavings–keratin hydrolysate (CSKH) complex. In this work, apart from elimination of tannery pollutants, a leather-like flexible sheet is obtained that can be used in the footwear and leather goods industry. In the scanning electrom microscopy evaluation, the surface morphology of the product exhibits smoothness because of the incorporation of poly(vinyl alcohol) and ethylene glycol. The above findings will open new avenues for further research in solid and liquid waste management of tannery effluents.