CAS: REGENERABLE POLYMERS FOR PHOSPHATE REMOVAL AND RECOVERY FROM WASTEWATER

With the support of the Macromolecular, Supramolecular and Nanochemistry (MSN) program in the Division of Chemistry, Professor Valerie Pierre of the University of Minnesota will be developing polymer-supported receptors that capture and release phosphate reversibly as needed for remediation and purification of waste water and for recycling phosphate—a critical resource needed to secure our food supply. Professor Pierre and her research team aim to synthesize and study polymers and receptors that function as sponges, capturing the phosphate from polluted water selectively and then releasing it upon addition of stimuli such as light or pressure. This controlled reversibility is designed to enable separation and recovery of phosphate and reagent-less recovery of smart receptors. This interdisciplinary research project will provide training opportunities to undergraduate and graduate students across a range of useful skills, including chemical synthesis, polymer characterization, and analytical studies of the receptor-phosphate binding. Broader impacts of the project also include the development and evaluation of new hands-on activities for middle schools, with the goal of increasing interest in science and the research enterprise in students early in their education. The Pierre research team seeks to develop a general strategy based on allosteric electrostatic interactions to render receptors for ions responsive to external stimuli. A unique aspect of these receptors is their ability to release their guests on demand upon addition of an external physical or chemical stimulus. The catch-and-release properties of such designed receptors rely on reversible chemical reactions, such as those governed by light, redox potential, temperature, and pressure. This controlled reversibility is expected to enable separation followed by controlled recovery of phosphate and reagent-less recovery of receptors supported on smart polymers. This approach broadens the capabilities of supramolecular ion receptors by enabling them to release the guests up a concentration gradient. The Minnesota research team further seeks to combine the strength of supramolecular chemistry with that of polymer science to enable solid support control of the behavior of the supported receptors. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.