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Wastewater containing heavy metal ions is one of the primary sources of water pollution, which has caused great endangerment on the human society. Therefore, searching for a chelating adsorption material without pollution, which can separate and recover metal ions efficiently, has great value for environment protection and resource recycle.The TA-CTS micro-bead, a new type chelating material, was synthesized by Inverse Suspension polymerization, and, its properties were investigated under static adsorption condition. It showed that: (1) The TA-CTS micro-bead with the cross-linking network had many advantages such as simple producing process, low cost, easy degradation in nature and none secondary pollution. Also it only swelled in acid solutions without flowing away, with a highly adsorption capacity after regenerated. (2) Its swelling degree was as low as 1.10 in distilled water. (3).The TA-CTS also had powerful adsorption capacity for Cd2+, Cu2+, Pb2+, which was greatly affected by the pH. The maximal adsorption capacity for Cd2+, Cu2+, Pb2+ was 0.58 mmol/g, 1.67 mmol/g, 0.59 mmol/g, with its optimal pH 6.0, 5.0, 6.5, respectively.The possible adsorption mechanism was speculated. The function groups of–OH and -NH2 in the surface of TA-CTS micro-bead offered lonely pairing electrons, which can form Coordination bond together with Space orbit provided by metal ions. The probable elution mechanism was as follows.Hydrogen ions and metal ions had the relationship of competing adsorption. The hydrogen ions took place of these metal ions when high concentration of the hydrogen ions existed in the solvent.With the self-made TA-CTS micro-bead, the SPE volumn was assembled. The influencing factors about adsorption and its pH-sensitivity are also investigated. The results indicated that:(1)The optimal absorption speed and concentration varied with different metal ions. The optimal absorption speed was 2 mL/min for Cd2+,1-5mL/min for Cu2+ ;The adsorption ratio reached 100% for Cd2+ between 0.2 mg/L- 10mg/L. And the optimal absorption concentration was 15 mg/L for Cu2+.(2)The pH-sensitivity of SPE column varied with different metal ions.The pH-sensitive values of SPE volumn for Cd2+,Cu2+ ,Pb2+ were 1.30,1.00,1.00,respectively;And the optimal dosage of eluent were 5mL,7mL,5mLforCd2+,Cu2+,Pb2+.To sum up, TA-CTS volumn could purificate wastewater by separating heavy metal ions efficiently.
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