Abatement technologies for copper containing industrial wastewater effluents – A review

The extensive application of copper in numerous industries leads to its accumulation in the environment, imposing severe toxic and carcinogenic health effects to human. In this article, the recent advances of abatement technologies for copper containing industrial wastewater were reviewed, including adsorption, electrochemical, and precipitation/crystallization processes. Adsorption is effective in treating dilute copper wastewater. Several adsorbents derived from biomass and clay have been developed, as well as the nano-sized and composite adsorbents. Electrochemical treatments such as electrodialysis, electrocoagulation, and capacitive deionization are also in demand due to its versatility, minimal use of chemical reagents, and compact design. Precipitation and crystallization techniques, including the emerging fluidized bed homogeneous crystallization process, are improved not only to provide effective removal but also to recover copper as sparingly soluble salts which can be further utilized for other industrial and scientific purposes. The abatement technologies for Cu(II) were compared to provide guidelines for the selection of processes based on the characteristics of wastewater. Ultimately, the limitation of the processes was summarized to reveal the perspectives in future research.