Easily recoverable paper-type AlOOH-incorporated PVDF adsorbents for efficient fluoride ion removal under diverse wastewater conditions

Abstract

As the environmental regulations in industrial processes become more stringent, the demand for cost-effective and convenient pollutant adsorbents, particularly fluoride ions, has intensified. This study presents a paper-type adsorbent, PA-1.25, integrating synthesized AlOOH with a high fluoride ion removal rate into polyvinylidene fluoride (PVDF). Unlike powder-type adsorbents, PA-1.25 offers a simplified recovery process with a 100% adsorbent recovery rate, eliminating the risk of secondary contamination. By addressing the inherent hydrophobicity of PVDF, PA-1.25 achieves improved water compatibility, enhancing its practical applicability in aqueous environments. At the same time, 95% of the incorporated AlOOH engages in fluoride ion adsorption, with an adsorption capacity of 6.26 mg/g, effectively reducing fluoride levels to meet the WHO guidelines of 1.5 mg/L. The high point of zero charge (10.6) in synthesized AlOOH ensures PA-1.25 performs consistently across a wide pH range. Additionally, PA-1.25 shows stable performance with co-existing ions and in industrial wastewater. PA-1.25 prevents adsorbent leakage and shows high efficiency in diverse wastewater environments, promising broad applications in environmentally friendly water treatment.