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• An electrode based on MOF-derived Al/C was developed for phosphate removal. • Al/C prepared by two-step calcination showed a stable and conductive structure. • The electrode affords a maximum adsorption capacity of 97.73 mg P/g for 1 V condition. • The electrode could be directly separated from the treated wastewater. • The desorption efficiency reached 89% in 20 min. Porous metal-organic frameworks (MOFs) have drawn increasing attention as promising phosphate adsorbents. Yet the potential agglomeration of MOFs particles and the difficult collection process largely thwarted their application. Meanwhile, adsorbents regeneration might destroy MOFs structures due to the use of strong alkaline solution. In this work, we reported a strategy for designing and fabricating an electrode to remove phosphate based on MIL-101 derived metal/carbon via a two-step carbonization step, which not only introduced C doping but also created a stable structure. With the assistance of electric field, the migration and capture of phosphate anions were greatly enhanced. Under 1 V condition, the material exhibited a high maximum removal capacity of 97.73 mg P/g. Adsorption kinetics and parameters for phosphate at different conditions were analyzed. Langmuir and Freundlich isotherms were employed to validate the adsorption data. More importantly, the regeneration of electrode was achieved in a more facile and efficient way than micro/ nanoparticles adsorbents by simple voltage control. Such an intriguing approach may provide a new platform to further expand the use of MOFs for adsorption process. Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • A macroporous MF-HA was prepared via a facile adsorbing method for phosphate removal. • MF-HA could effectively adsorb phosphate over a wide pH range with high selectivity. • Phosphate of 3 mg P/L could be reduced to 0.0015 mg/L. • MF-HA could be easily separated after adsorption with good recyclability. • The cost-efficient raw materials and simple engineering improved its practicality. Effective removal of phosphate from aqueous solution is of great significance in environmental protection. In this paper, the concept of developing a hierarchical and cost-effective aluminum functionalized melamine foam (MF) as phosphate adsorbent is presented. The material with 3D interconnected network, flexibility and ultralow density was fabricated via a simple adsorbing method based on hydrate aluminum and commercially available MF sponge. For use as an adsorbent, performance of the as-prepared MF-HA sponge was assessed with various pH, temperatures, adsorption time, initial P concentrations, ionic strengths and co-existing ions. The experimental results demonstrated that MF-HA performed well in a wide pH range of 4–10 and in the presence of foreign anions, with high maximum uptake capacity of 36.21 mg P/g. Furthermore, for the as-prepared material, the phosphate removal performance at different temperatures established the endothermic nature of the adsorption process. Moreover, MF-HA sponge could be directly separated from the solution and showed a satisfactory recyclability. The adsorbing strategy to design and fabricate the novel sponge with resultant high adsorption efficiency, cost-effectiveness, preferable selectivity, environmental friendliness, and easy separation from water may promote sponge functionalization for applications in extensive wastewater treatment areas. [ABSTRACT FROM AUTHOR]

[Display omitted] • A macroporous MF-HA was prepared via a facile adsorbing method for phosphate removal. • MF-HA could effectively adsorb phosphate over a wide pH range with high selectivity. • Phosphate of 3 mg P/L could be reduced to 0.0015 mg/L. • MF-HA could be easily separated after adsorption with good recyclability. • The cost-efficient raw materials and simple engineering improved its practicality. Effective removal of phosphate from aqueous solution is of great significance in environmental protection. In this paper, the concept of developing a hierarchical and cost-effective aluminum functionalized melamine foam (MF) as phosphate adsorbent is presented. The material with 3D interconnected network, flexibility and ultralow density was fabricated via a simple adsorbing method based on hydrate aluminum and commercially available MF sponge. For use as an adsorbent, performance of the as-prepared MF-HA sponge was assessed with various pH, temperatures, adsorption time, initial P concentrations, ionic strengths and co-existing ions. The experimental results demonstrated that MF-HA performed well in a wide pH range of 4–10 and in the presence of foreign anions, with high maximum uptake capacity of 36.21 mg P/g. Furthermore, for the as-prepared material, the phosphate removal performance at different temperatures established the endothermic nature of the adsorption process. Moreover, MF-HA sponge could be directly separated from the solution and showed a satisfactory recyclability. The adsorbing strategy to design and fabricate the novel sponge with resultant high adsorption efficiency, cost-effectiveness, preferable selectivity, environmental friendliness, and easy separation from water may promote sponge functionalization for applications in extensive wastewater treatment areas. [ABSTRACT FROM AUTHOR]