Assessment of Molecularly Imprinted Polymers as Phosphate Sorbents
Abstract
Wastewater effluents and agricultural runoff are major sources of phosphorus overloading in surface waters. Phosphorus overloading ignites eutrophication, which devastates aquatic ecosystems. On the other hand, phosphorus, which is currently produced from phosphate rock, is a critical component of fertilizer mixes. However, the world is predicted to face a shortage of phosphate supply beyond 2033 due to unsustainable mining. This research aims to develop a polymeric sorbent that recovers low-concentration phosphorus for eutrophication prevention and fertilizer reuse. Available polymer-based products have underwhelmed expectations by having poor selectivity or lacking appropriate biodegradation rates. This research identified molecularly imprinted polymers (MIPs) as possible sorbents for overcoming the deficiencies of reported technologies. Screening of several MIPs resulted in one potentially feasible MIP for phosphate sorption. Further studies showed a sorption capacity of ~28 mg PO43--P/g and partial phosphate-selectivity. Potential phosphate removal mechanisms were identified, providing foresight into MIPs’ viability as phosphorus sorbents.