摘要
Hydrogel materials have garnered significant attention for the removal and recovery of phosphorus (P) from wastewater owing to their rapid reactivity, operational ease, and straightforward recovery process. Herein, thermo-responsive/low-fouling poly(sulfobetain methacrylate) (PSBMA) hydrogels encapsulating hydrous zirconium oxide (PSBMA-HZO) were prepared by a simple and efficient approach for the selective enrichment of P from wastewater, subsequently integrated with the electrochemically-driven struvite precipitation (ESP) process for P recovery as struvite. The PSBMA-HZO hydrogels were investigated using TEM, SEM-EDS, XRD, FTIR, swelling kinetics, mechanical strength testing, TGA, and XPS studies. The adsorption studies demonstrated that the composite hydrogels exhibited significant selectivity for P removal, affording a maximum adsorption capacity of 35.54 mg P/g at pH 2 and 25 °C. Additionally, the thermos-responsive characteristic of PSBMA-HZO hydrogels had been demonstrated to enhance the adsorption/desorption capabilities over ten cycles of regeneration studies. Moreover, the composite hydrogels exhibited remarkable reusability and antifouling properties. The adsorption mechanisms may encompass electrostatic attraction, ligand exchange and Lewis acid-base interactions. Results from P recovery tests using real wastewater indicated that a P-enriched eluate (88.95 mg P/L) was yielded following five adsorption–desorption cycles when the composite hydrogels were applied in the pretreated anaerobic digestion effluent (129.07 mg P/L) with a high concentration of organics. The precipitated products obtained from the eluate via ESP contained struvite with a purity of 65.3 %. This study revealed that the PSBMA-HZO-facilitated adsorption/desorption in conjunction with ESP can serve as a viable method for recovering P resources as struvite products for practical applications.
危险品化学品经营许可证（带存储）