四乙烯五胺多(二硫代甲酸钠)的合成及其对重金属的去除性能

以四乙烯五胺(TEPA)，NaOH和CS₂为原料，在无水乙醇中合成四乙烯五胺多(二硫代甲酸钠，TEPAMDT)，采用红外光谱和紫外光谱对其结构进行表征，测定了其对游离和络合Cu2+及Ni2+废水的处理效果，通过扫描电镜和电子能谱考察了絮体的形貌和组成. 结果表明，处理游离Cu2+和Ni2+废水，TEPAMDT中n(CSS-)∶n(Cu2+)和n(CSS-)∶n(Ni2+)分别为1.94∶1和2.00∶1时，去除率分别达99.90%和99.80%以上；处理50 mg/L n(硫脲)∶n(Cu2+)和n(柠檬酸)∶n(Cu2+)均为1∶1的废水，当n(CSS-)∶n(Cu2+)分别为2.05∶1和2.12∶1时，去除率分别达99.98%和99.94%；处理50 mg/L n(硫脲)∶n(Ni2+)和n(柠檬酸)∶n(Ni2+)均为1∶1的废水，当n(CSS-)∶n(Ni2+)分别为2.10∶1和2.19∶1时，去除率分别达99.93%和99.91%. 絮凝和能谱分析结果表明，TEPAMDT中CSS-与Cu2+或Ni2+都按2∶1的化学计量比生成螯合物，TEPAMDT具有较宽的pH适用范围. 

Synthesis of a Sodion Tetraethylenepentamine-multi Dithiocarbamate and Its Removal Performance for Heavy Metals

A sodion tetraethylenepentamine-multi dithiocarbamate(TEPAMDT) was prepared from tetraethylenepentamine(TEPA),NaOH and CS2 in anhydrous ethanol,and its structures were characterized by FTIR and ultraviolet spectroscopy.Itsremoval efficiencies for free or complex Cu2 + and Ni2 + in wastewater were determined,and floc images and compositions wereinvestigated by using scanning electron microscope and energy spectrum analysis,respectively.The results show that,for heavymetal wastewater containing free Cu2 + or Ni2 +,when the molar ratios of CSS-to Cu2 + and Ni2 + were 1.94∶1 and 2.00∶ 1,respectively,the removal rates of Cu2 + and Ni2 + were above 99.90% and 99.80%,respectively.For heavy metal wastewatercontaining 50 mg /L Cu2 +-thiourea or Cu2 +-citric acid complexes with molar ratio of chelating agent to Cu2 + of 1∶1,when the molarratios of CSS-to Cu2 + were 2.05∶1 and 2.12∶1,respectively,the removal rates of Cu2 + were up to 99.98% and 99.94%,respectively.For heavy metal wastewater containing 50 mg /L Ni2 +-thiourea or Ni2 +-citric acid complexes with molar ratio ofchelating agent to Ni2 + of 1∶1,when the molar ratios of CSS-to Ni2 + were 2.10∶1 and 2.19∶1,respectively,the removalrates of Ni2 + were up to 99.93% and 99.91%,respectively.Both flocculation and energy spectrum analysis results indicated that CSS-reacts with Cu2 + or Ni2 + to form chelates accordingto a stoichiometric ratio of 2∶1,and TEPAMDT has a widelysuitable pH range.