Smart Organic–Inorganic Polyoxomolybdates in Forward Osmosis for Antiviral-Drug Wastewater Treatment and Drug Reclamation

• Published in: Environmental science & technology Vol. 57; no. 14; pp. 5872 - 5880
• Main Authors: Zou, Yiting, Ge, Qingchun
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 11.04.2023
• Subjects: Acidification; Antiviral agents; COVID-19; Drugs; Humans; Medical wastes; Membranes, Artificial; Osmosis; Pandemics; Reclamation; Sodium Chloride; Solutes; Solutions - chemistry; Treatment and Resource Recovery; Wastewater; Wastewater renovation; Wastewater treatment; Water - chemistry; Water Purification; Water reclamation; Water treatment; forward osmosis; antiviral-drug wastewater; polyoxomolybdate; drug reclamation; smart draw solute
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/acs.est.3c00084

The demand to effectively treat medical wastewater has escalated with the much greater use of antiviral drugs since the COVID-19 pandemic. Forward osmosis (FO) has great potential in wastewater treatment only when appropriate draw solutes are available. Here, we synthesize a series of smart organic–inorganic polyoxomolybdates (POMs), namely, (NH4)6[Mo7O24], (PrNH3)6[Mo7O24], (iPrNH3)6[Mo7O24], and (BuNH3)6[Mo7O24], for FO to treat antiviral-drug wastewater. Influential factors of separation performance have been systematically studied by tailoring the structure, organic characteristics, and cation chain length of POMs. POMs at 0.4 M produce water fluxes ranging from 14.0 to 16.4 LMH with negligible solute losses, at least 116% higher than those of NaCl, NH4HCO3, and other draw solutes. (NH4)6[Mo7O24] creates a water flux of 11.2 LMH, increased by more than 200% compared to that of NaCl and NH4HCO3 in long-term antiviral-drug wastewater reclamation. Remarkably, the drugs treated with NH4HCO3 and NaCl are either contaminated or denatured, while those with (NH4)6[Mo7O24] remain intact. Moreover, these POMs are recovered by sunlight-assisted acidification owing to their light and pH dual sensitivity and reusability for FO. POMs prove their suitability as draw solutes and demonstrate their superiority over the commonly studied draw solutes in wastewater treatment.