Insight into the synthesis and adsorption mechanism of adsorbents for efficient phosphate removal: Exploration from synthesis to modification

Chemical adsorption is widely used in deep phosphorus removal because of its simple procedure, high treatment efficiency, and convenient recovery. Development of adsorption materials with a large specific surface area (SSA), coordinated porosity, and designable morphology opens up new avenues for better phosphate adsorption performance, and eliminates the interactive effects of environmental factors (pH, coexisting ions, etc.) on phosphate adsorption. This critical review first presents the systematic summary of the research progress on synthesis methods to prepare adsorption materials and modification strategies of different adsorbents, which enhance the specificity toward phosphate and accelerate the adsorption rate of phosphate. Further, the effect of SSA and functional groups on phosphate adsorption mechanism is analyzed. Finally, details about the process of recovering phosphorus resources are discussed, as well as the trend and prospect of machine learning guided material design is presented. This review can provide new insights into the research on high-performance adsorbent materials for phosphate removal in the future.