Engineered PVA aerogels for effective mercury species removal with quick regeneration in wastewater remediation

Mercury pollutants, particularly ionic mercury (Hg2+), have been identified by the World Health Organization as among the top ten chemicals posing a significant threat to public health. Adsorption of Hg2+ onto solid phases has emerged as an effective method for water remediation. However, most existing adsorbents suffer from drawbacks such as complex preparation procedures, secondary pollution, and time-consuming regeneration processes. To address these limitations, we have developed an aerogel adsorbent based on poly(vinyl alcohol) and the auxiliary crosslinker phytic acid. This aerogel can be easily synthesized via a self-assembly process under hydrothermal conditions, offering advantages including excellent mechanical strength, adjustable pore size, and surface area. The aerogel exhibits remarkable adsorption capacity for both Hg2+ and organic mercury compounds (MeHg+), and can be regenerated within an incredibly short time (~40 s). Moreover, it demonstrates high removal efficiency of Hg2+ even in the presence of competing ions such as Mn2+, Cd2+, Cr2+, Cu2+, and Pb2+. The low-cost raw materials, straightforward synthesis, and facile manipulation during the remediation/regeneration process make this aerogel adsorbent highly promising for practical applications in real-world scenarios.