N-硫代酰基硫乙酸功能化三乙撑四胺交联PVC树脂的制备及对Hg~(2+)的吸附

以聚氯乙烯为原料依次与四乙烯五胺、CS_2和ClCH_2COONa反应合成了一种新的含N、O、S的N-硫代酰基硫乙酸功能化三乙撑四胺交联聚氯乙烯螯合树脂,树脂结构经红外分析和元素分析表征. 探讨了在不同pH值、Hg~(2+)初始浓度、吸附温度和时间等条件下合成树脂对Hg~(2+)的吸附性能. 结果表明,螯合树脂对Hg~(2+)有较快的吸附速率,pH值约为2.0时,树脂对Hg~(2+)的吸附效果最好,随温度升高吸附量逐渐增大. 温度在35 ℃、Hg~(2+)起始浓度为17.66 mmol/L时,树脂对Hg~(2+)的吸附量可达3.330 mmol/g. 树脂对Hg~(2+)的吸附符合Langmuir和Freundlich等温式. 用0.2 mol/L HNO3-10%硫脲对吸附后的树脂进行洗脱,脱附率达99.20%.

Preparation and Hg~(2+) Adsorption of N-thioacyl Thioglycolic Acid Functionalized Triethylenetetramine Crosslinked PVC Resin

A novel acidic N-thioacyl thioglycolic acid functionalized triethylentetramine crosslinked PVC resin was preparated from PVC, triethylenetetramine, CS_2 and ClCH_2COONa and characterized by FTIR and elemental analysis. Adsorption properties of the resin for Hg~(2+) were investigated under different conditions such as pH, temperature, contact time and the initial concentration of Hg~(2+). The results show that the adsorption of the resin for Hg~(2+) could rapidly reach balance, and it displayed a higher capacity when pH was about 2.0. The adsorption capacity of the resin for Hg~(2+) reached 3.330 mmol/g at 35 ℃ and 17.66 mmol/L Hg~(2+). The adsorption process was fitted to Langmuir and Freundlich isotherms in the studied concentration range. The loaded resin with Hg~(2+) was regenerated in an efficiency of 99.2% via 0.2 mol/L HNO_3-10% thiourea.