Reclamation of EDTA by sodium tetraethylenepentamine-multi dithiocarbamate after soil washing process with EDTA
Reclamation of EDTA by sodium tetraethylenepentamine-multi dithiocarbamate after soil washing process with EDTA
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EDTA洗土后四亚乙基五胺多二硫代氨基甲酸钠回收EDTA
DOI：
10.1007/s12665-017-6587-8
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发表时间：
2017-04
影响因子：
2.8
通讯作者：
Li Fengting
中科院分区：
文献类型：
--
作者：
Wang Yan;Zhang Bingru;Deng Tianlin;Li Fengting
乙二胺四乙酸（EDTA）已被证明是一种去除土壤中金属污染物的有效土壤洗涤液。但EDTA在洗涤过程中如果不回收或破坏，其生物降解性较低，可能造成二次污染。因此，有必要对EDTA进行循环利用和回收，以实现可持续利用。本文首先研究了EDTA的提取性能与EDTA浓度、液沉比（L/S）、溶液pH和提取时间的关系。在刘丽华研究的基础上，合成了重金属捕集剂四乙二胺多元二硫氨基甲酸钠（TEPA-DTC）。与Na2S和DDTC相比，TEPA-DTC表现出较强的螯合能力，因为它具有二硫代氨基甲酸酯官能团，可以强螯合重金属，并从Me-EDTA中捕获金属离子形成沉淀，使我们能够在土壤洗涤过程中回收EDTA。研究了三种二价重金属（Pb、Cd和Cu）。在300 mg/l的TEPA-DTC作用下，这三种金属几乎完全沉淀，EDTA再生。回收的EDTA在三次洗土循环中再次使用，每次循环中重金属的提取量都略有下降。
Ethylenediaminetetraaceticacid (EDTA) has been proven to be an efficient soil washing liquid to remove metal contaminants from soils. However, EDTA may cause secondary pollution due to its low biodegradability if it is not recycled or destroyed in the washing process. Thus, it is necessary to recycle and recover EDTA for sustainable use. In this paper, the extracting performance of fresh EDTA was firstly studied as a function of EDTA concentration, liquid/sediment (L/S) ratio and pH of the solution, and also extraction time. Then sodium tetraethylenepentamine-multi dithiocarbamate (TEPA-DTC), a heavy metals capturing agent, was synthesized on the base of the research of LIU-Lihua. Compared with Na2S and DDTC, TEPA-DTC shows strong chelating capacity, because it has functional groups of dithiocarbamate that could strongly chelate heavy metals and capture metal ions from Me-EDTA to form precipitates, allowing us to reclaim the EDTA during the process of soil washing. Three divalent heavy metals were investigated (Pb, Cd, and Cu). These three metals could almost precipitate completely with TEPA-DTC under the dosage of 300 mg/l, and EDTA was regenerated. The recovered EDTA was used again in three cycles of soil washing, and the amount of heavy metals extracted just slightly decreased each cycle.
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影响因子：
--
作者：
Ling Yulin
通讯作者：
Ling Yulin
影响因子：
11.4
作者：
KUMAR, PBAN;DUSHENKOV, V;RASKIN, I
通讯作者：
RASKIN, I
影响因子：
8.9
作者：
Sun, B;Zhao, FJ;McGrath, SP
通讯作者：
McGrath, SP
影响因子：
3.7
作者：
Qihang Wu;Shizhong Wang;P. Thangavel;Qingfei Li;Handou Zheng;Jun Bai;R. Qiu
通讯作者：
Qihang Wu;Shizhong Wang;P. Thangavel;Qingfei Li;Handou Zheng;Jun Bai;R. Qiu
影响因子：
8.8
作者：
M. Pociecha;D. Lestan
通讯作者：
M. Pociecha;D. Lestan