Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210098, China.
J Environ Sci (China). 2011;23(5):778-83. doi: 10.1016/s1001-0742(10)60477-9.
Potassium butyl dithiophosphate (PBD) was developed and introduced as a new chelating agent for heavy metal removal. The synthesized PBD were characterized by IR and NMR. The effects of pH, chelating agent dosage, and other heavy metal ions on the performance of PBD in Cd2+ removal from water are investigated. Experimental results showed that the chelating agent could be used to treat acidic heavy metal wastewater. The Cd2+ removal was not affected by solution pH value within the range of 2 to 6. The Cd2+ removal rate could reach over 99%. Therefore, the deficiency of the precipitation process using hydroxide under alkaline condition can be overcome. Without the need for pH adjustment, the method could save on costs. If Cd2+ co-exists with Pb2+ and Cu2+, the affinity of the chelating agent with these three heavy metal ions was in the order of: Cu2+ > Pb2+ > Cd2+. Through PBD chelating precipitation, all the contents of Pb2+, Cd2+, and Cu2+ in wastewater met the standard levels through a one-step treatment. The one-step treatment process was superior to the process (sectional treatment is required) of precipitation with hydroxide. When the pH was between 3 and 11, the amount of leached chelated Cd2+ was much lower than that obtained by precipitation with hydroxide. Therefore, the risk of environmental pollution could be further reduced.
丁基二硫代磷酸钾（PBD）是作为一种新型重金属螯合剂而被开发和引入的。合成的 PBD 通过 IR 和 NMR 进行了表征。研究了 pH 值、螯合剂用量和其他重金属离子对 PBD 从水中去除 Cd2+性能的影响。实验结果表明，该螯合剂可用于处理酸性重金属废水。Cd2+的去除不受溶液 pH 值在 2 到 6 范围内的影响。Cd2+的去除率可达 99%以上。因此，可以克服使用氢氧化物在碱性条件下沉淀过程的不足。无需进行 pH 值调整，该方法可节省成本。如果 Cd2+与 Pb2+和 Cu2+共存，螯合剂与这三种重金属离子的亲和力顺序为：Cu2+>Pb2+>Cd2+。通过 PBD 螯合沉淀，废水中的所有 Pb2+、Cd2+和 Cu2+含量均通过一步处理达到标准水平。一步处理工艺优于使用氢氧化物沉淀的工艺（需要分段处理）。当 pH 值在 3 到 11 之间时，浸出的螯合 Cd2+的量远低于使用氢氧化物沉淀得到的量。因此，可以进一步降低环境污染的风险。
