School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China.
Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China; Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, USA.
Sci Total Environ. 2020 Jan 1;698:134270. doi: 10.1016/j.scitotenv.2019.134270. Epub 2019 Sep 3.
The removal of lead in water and disposal of tailings are important environmental issues that need to be addressed urgently. This work explored the feasibility of utilizing the carbonate-based tailings (CBT) for removing lead from the simulated wastewater with the aid of wet stirred ball milling (mechanical activation). Batch experiments were performed to evaluate the influences of various experimental parameters like dosage of CBT, milling balls addition and initial concentration of lead. Under the action of mechanical activated CBT, the lead removal in the solution could reach more than 99% in 2 h, and the lead removal capacity reached 832 mg/g. The results of X-Ray Diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR) and Scanning Electron Microscope-Energy Dispersive Spectra (SEM-EDS) revealed that the calcite (CaCO) in CBT played a major role in removing lead and the lead in the solution was transferred to the precipitate as cerussite (PbCO). The mechanical activation promoted the dissolution of calcite, reduced the particle size of CBT and peeled off the lead carbonate precipitation on the surface of calcite, thereby enabling the reaction to be efficiently and thoroughly completed. The lead content in the precipitate after the reaction reached 38.4 wt%, which made it possible for lead recovery.
水和尾矿中的铅去除是需要紧急解决的重要环境问题。本工作探索了利用碳酸盐尾矿（CBT）在湿搅拌球磨（机械活化）辅助下从模拟废水中去除铅的可行性。进行了批实验以评估各种实验参数的影响，例如 CBT 的用量、磨球的添加和铅的初始浓度。在机械活化 CBT 的作用下，溶液中的铅去除率在 2 小时内可达 99%以上，铅去除容量达到 832mg/g。X 射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和扫描电子显微镜-能量色散谱（SEM-EDS）的结果表明，CBT 中的方解石（CaCO）在去除铅方面起着主要作用，溶液中的铅被转移到沉淀中作为碳酸铅（PbCO）。机械活化促进了方解石的溶解，减小了 CBT 的粒径，并从方解石表面剥落了碳酸铅沉淀，从而使反应能够高效、彻底地完成。反应后沉淀中的铅含量达到 38.4wt%，这使得铅的回收成为可能。
