新型DTC类络合重金属捕集剂的合成及其在废水处理中的应用

Synthesis and application in wastewater of a novel type of dithiocarbamate (DTC)-based heavy metal chelating agent

为了更有效地去除废水中络合态重金属离子且不添加任何絮凝剂,合成了一种新型的重金属捕集剂聚-二硫代氨基甲酸铵(PADTC),并采用傅里叶红外光谱,核磁共振,元素分析和凝胶渗透色谱推测产物结构。考察反应时间、pH对重捕剂去除效果的影响,结果表明:在pH=6、反应时间为20 min时,Cu^(2+)、Ni^(2+)和Zn^(2+)的最大吸附能力分别为246、234和227 mg·g^(-1);同时还探讨了不同络合剂的吸附影响,其去除顺序为TA>CA>EDTA。在实际废水处理中,PADTC取得了良好的处理效果。通过FT-IR、SEM-EDS和XPS表征证实了PADTC对络合重金属的抓捕机理。使用PADTC从废水中去除重金属可能具有良好的工业发展前景。

To remove chelated heavy metals more efficiently without the addition of flocculant, a novel type of poly-ammonium dithiocarbamate （PADTC） based heavy metal chelating agent was synthesized, and the structure of which was characterized using FT-IR, NMR and element analysis as well. Effects of reaction time and pH on the removal efficiency were also investigated, it was found that at the pH of 6 and the reaction time adopted as 20 minutes, the maximum adsorption capacities for chelated Cu2＋, Ni2＋ and Zn2＋ reached 246, 234 and 227 mg·g-1, respectively. The adsorption effect of different complexing agents was also conducted, and the removal order was confirmed as TA 〉 CA 〉 EDTA. Application of PADTC in the actual electroplating wastewater performed well for the removal of chelated heavy metal. The capture mechanism of PADTC for chelated heavy metals was conducted and then proposed by FT-IR, SEM-EDS and XPS characterization. Removal of chelated heavy metals from metal processing wastewater using PADTC might be of industrial potential.