IDENTIFICATION OF LEAD UNION SITES ON THE HAIR ADSORBENT SURFACE OF THE TANNERY INDUSTRY

Abstract

The objective of this research was to identify the functional groups that are responsible for the adsorption of Pb (II) on the treated hair residues of the enzymatic unhairing process of the tanneries. For this purpose was made the preparation of adsorbent, which consisted in washing hair residues in order to deliming and lower the pH of 12 to neutral, after which they were dried and was applied these the treatment of acid hydrolysis, at the end of which these were washed, dried and ground. Then the hairs treated with the Pb (II) solution were placed in agitation in a range of time and pH, for the study of adsorption isotherms and the kinetic study. At the end of which a chemical characterization was carried out through the FTIR analysis and the XRD analysis. Thus also a physical characterization with a SEM analysis, by means of two detectors of the equipment. These analyses were carried out in 3 samples being these residues of hairs without and with treatment and the residues of treated hairs used in the adsorption of Pb (II). The results obtained showed that the functional groups responsible for the adsorption of Pb (II) are the carboxyl, amino and the groups containing sulphur (S = O), which are on the surface of the bioadsorbent