Removal and recovery of phosphonates from wastewater via adsorption

Over the past decades, the increasing consumption of phosphonates, which are limited resources, has attracted greater attention at the world level. Phosphonate in wastewater is a crucial resource while it may cause eutrophication as a serious environmental problem. Hence phosphonates removal and recovery from wastewater are crucial for sustainable development consideration. Adsorption as a cost-effective technology for low-concentration phosphonates resource utilization has contributed to sustainable wastewater treatment practices. Nevertheless, a systematic review on phosphonates removal and recovery from wastewater via economically realistic adsorption technique is still missing and therefore is realized in this review, especially regarding novel adsorbents. Additionally, we discussed the influence of pH and metal ions on adsorption performance and the role of characterization and chemical computation techniques for phosphonates removal mechanism. The recently established novel adsorbents (granular ferric hydroxide, ZnFeZr@MP, La/Zn/Fe3O4@PAC, Zr-La@Fe3O4, and montmorillonite) provided good adsorption capacity and removal efficiency of phosphonates. Specifically, the ZnFeZr@MP was implemented for practical application in industrial and municipal wastewater, and ZnFeZr-oxyhydroxide suggested a potential endothermic process could be realized in application practices. High desorption efficiency typically obtained by ZnFeZr (NTMP-90%; DTPMP-100%), Zr-La@Fe3O4 (96.1% and 101.8%), and clay minerals (100%) from the reusability tests. During the practically column breakthrough treatment >90% removal efficiency and 78% desorption efficiency of NTMP were achieved from membrane concentrate. Further, various modern characterization tools enhanced the investigation of phosphonate removal mechanisms. Thus, this review article is recommended to explore the mechanism for phosphonate removal and adsorption via characterization and chemical computation techniques in the future.