Experimental Study on Enhanced Phosphorus Removal Using Zirconium Oxychloride Octahydrate-Modified Efficient Phosphorus Removal Composite

Abstract

In addressing eutrophication and enhancing water quality, this study builds upon previous research involving the development of an Efficient Phosphorus Removal Composite (EPRC), a material created using modified industrial wastes (steel slag and fly ash) as adsorbent substrates, supplemented with a binder and porosity-forming agent. In this investigation, the EPRC was further enhanced through the addition of zirconium oxychloride octahydrate, resulting in the production of Zr-EPRC particles as reinforced phosphorus removal materials. Comparative experiments were conducted to assess different methods for preparing Zr-EPRC, the static adsorption performance, and dynamic adsorption behavior. The optimal preparation of Zr-EPRC was achieved by separately modifying the base materials, steel slag and fly ash. Loading with mass ratios of zirconium chloride octahydrate to fly ash and steel slag at 0.4 and 0.6, respectively, for a duration of 12 h at a pH of 10 yielded the best results. In static adsorption experiments conducted at temperatures of 15 °C, 25 °C, and 35 °C, Zr-EPRC exhibited saturated phosphorus adsorption capacities of 11.833 mg/g (variance = 0.993), 12.550 mg/g (variance = 0.993), and 13.462 mg/g (variance = 0.996), respectively. Zr-EPRC emerges as a cost-effective and readily available solution with promising stability for general wastewater treatment applications, contributing significantly to the mitigation of eutrophication and the improvement of water quality.