State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
J Environ Sci (China). 2023 Jul;129:115-127. doi: 10.1016/j.jes.2022.08.019. Epub 2022 Aug 30.
The selective recovery of copper from strongly acidic wastewater containing mixed metal ions remains a significant challenge. In this study, a novel reagent zinc dimethyldithiocarbamate (Zn(DMDC)) was developed for the selective removal of Cu(II). The removal efficiency of Cu(II) reached 99.6% after 120 min reaction at 30°C when the mole ratio Zn(DMDC)/Cu(II) was 1:1. The mechanism investigation indicates that the Cu(DMDC) products formed as a result of the displacement of Zn(II) from the added Zn(DMDC) by Cu(II) in wastewater, due to the formation of stronger coordination bonds between Cu(II) and the dithiocarbamate groups of Zn(DMDC). Subsequently, we put forward an innovative process of resource recovery for strongly acidic wastewater. Firstly, the selective removal of Cu(II) from actual wastewater using Zn(DMDC), with a removal efficiency of 99.7%. Secondly, high-value CuO was recovered by calcining the Cu(DMDC) at 800°C, with a copper recovery efficiency of 98.3%. Moreover, the residual As(III) and Cd(II) were removed by introducing HS gas, and the purified acidic wastewater was used to dissolve ZnO for preparation of valuable ZnSO·HO. The total economic benefit of resource recovery is estimated to be 11.54 $/m. Accordingly, this study provides a new route for the resource recovery of the treatment of copper-containing acidic wastewater.
从含有混合金属离子的强酸性废水中选择性回收铜仍然是一个重大挑战。在这项研究中，开发了一种新型试剂锌二甲基二硫代氨基甲酸盐（Zn(DMDC)），用于选择性去除 Cu(II)。当 30°C 下反应 120 分钟，Zn(DMDC)/Cu(II)摩尔比为 1:1 时，Cu(II)的去除效率达到 99.6%。机理研究表明，由于 Cu(II)与 Zn(DMDC)的二硫代氨基甲酸盐基团之间形成了更强的配位键，Cu(II)从废水中添加的 Zn(DMDC)中取代 Zn(II)，形成了 Cu(DMDC)产物。随后，我们提出了一种从强酸性废水中回收资源的创新工艺。首先，使用 Zn(DMDC)选择性地从实际废水中去除 Cu(II)，去除效率为 99.7%。其次，通过在 800°C 下煅烧 Cu(DMDC)回收高价值的 CuO，铜回收率为 98.3%。此外，通过引入 HS 气体去除残留的 As(III)和 Cd(II)，并将净化后的酸性废水用于溶解 ZnO 以制备有价值的 ZnSO·HO。资源回收的总经济效益估计为 11.54 美元/立方米。因此，本研究为含铜酸性废水处理的资源回收提供了一条新途径。
