Synthesis of sulfhydryl chitin and its adsorption properties for heavy metal ions

This article discusses the preparation of the water-insoluble adsorbent sulfhydryl chitin (s-chitin), by treatment of the chitin with sulfhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confirmed by elemental analysis, FTIR spectra analysis and near-IR spectra analysis. We also investigated the adsorption properties of sulfhydryl chitin for CuII, CdII, PbII, CrIII, and NiII. Based on the research results of adsorption capacity, the effect of pH value on adsorption, adsorption kinetics experiments, and selective adsorption experiments were observed. It has been shown that the s-chitin has much better adsorption for PbII, CuII, and CdII than chitin itself. The adsorption capacities of s-chitin for PbII, CuII, and CdII were 108.3, 94.7, and 57.1 mg/g, respectively. It also had good adsorption properties for heavy metal ions. The adsorption capacities were also affected by the acidity of medium. The adsorbed CuII, CdII, and PbII could be eluted by diluted chlorhydric acid.