Modification of the crosslinked hyperbranched polyamide-amines by thiourea and its selective adsorption for Cu (II)

A novel crosslinked hyperbranched polyamide-amines adsorbent (CHAP-SH) with sulfhydryl functional groups was synthesized by modifying thiourea and its selective adsorption properties for Cu (II) were studied. The adsorption of coexisting ions showed that the CHAP-SH had high adsorption capacity and selectivity for Cu (II). The adsorption characteristics and mechanism of the CHAP-SH for Cu (II) were systematically investigated. The results of shake flask adsorption experiments indicated that the adsorption procedure was well adapted to the Langmuir isotherm and pseudo-second-order kinetics models, and the maximum adsorption capacity of Cu (II) was 158.48 mg/g at pH = 5.0 and 45 ℃. The adsorption mechanism of the CHAP-SH for Cu (II) was mainly the synergistic interaction with –NH, –COO − , and –SH functional groups. After seven adsorption/desorption cycles, it could still maintain a high removal rate, which provided great potential for the development of multiple novel and reusable immobilized functional materials to efficiently isolate the Cu (II) ions.