Abstract:

Significance Per- and polyfluoroalkyl substances (PFASs) are persistent, bioaccumulative, and toxic pollutants widely used in textile dyeing printing industry as water-, oil-, and stain-repellent agents, making the industry wastewater be a major emission source, with PFAS concentrations in wastewater reported up to 4 268 ng/L, far higher than the background levels. Because of persistence and health risks like immunosuppression, PFASs are the main pollutants under the Stockholm Convention and national regulations. However, their removal from dyeing and printing wastewater remains challenging, where the conventional biological treatments exhibit low efficiency and risk generating mobile short-chain PFASs, the chemical oxidation may produce byproducts, membrane separation is costly, and biodegradation has limited effect. Despite its high efficiency and operational simplicity, the application of adsorption is hindered by the complex matrices of dyeing and printing wastewater. High salinity, variable pH value, and dissolved organic matter (DOM) impair short-chain PFAS selectivity, cause competitive adsorption, and increase regeneration costs. Recent studies take activated carbon, ion-exchange resins, metal-organic frameworks/covalent organic frameworks (MOFs/COFs), and fluorinated polymers as promising adsorbents, which are modified to improve selectivity and durability. By elucidating synergies among hydrophobic, electrostatic, and F-F interactions, structure-oriented design of advanced adsorbents enables sustainable and cost-effective solutions, thereby supporting the green transition of the textile industry and ensuring aquatic environmental safety.

Progress Recent research on PFASs adsorption from textile dyeing and printing wastewater has achieved notable progress in both materials and mechanisms. Conventional adsorbents such as activated carbon was improved by co-pyrolysis with red mud or ZnCl₂ activation, improving pore structures, surface activity, and resistance to DOM interference. Ion-exchange resins functionalized with hydrophobic or positively charged groups significantly improved short-chain PFAS removal. New fluorinated polymers demonstrated outstanding capacity. Perfluoropolyether-modified ion-exchange resin PFPE-IEX+ achieved 518.9 mg/g hexafluoropropylene oxide dimer acid (GenX) adsorption in saline, humic acid-rich water through synergistic fluorine-fluorine and electrostatic interactions. Type I fluorine-fluorine interactions were adopted to optimize adsorption energy and molecular recognition. Hydrophobic interfacial nanobubbles enriched long-chain PFASs, with degassing reducing PFOS uptake by 17%-26%. Ca²⁺ ions were found to mitigate DOM inhibition via a ″bridging effect″. Representative materials such as strong-base anion exchange resins, thermally regenerable hydrotalcite, and PFPE-IEX+ highlighted the practical potential. These advances collectively drive adsorption technology toward multi-mechanism synergy, reduced energy demand, and precise PFAS targeting, offering sustainable solutions for textile wastewater treatment.

Conclusion and Prospect Substantial breakthroughs have been achieved in the adsorption-based removal of PFASs, demonstrating significant potential for treating textile dyeing and printing wastewater. By leveraging multi-mechanism synergy-combining hydrophobic, electrostatic, and fluorine-fluorine interactions, novel adsorbents demonstrated markedly improved adsorption capacity and selectivity for PFASs. These materials exhibit strong anti-interference in complex water matrices, facing challenges such as high salinity, pH variation, and DOM competition. Adsorption kinetics have been advanced by orders of magnitude, nearing instantaneous response for some materials. Regeneration strategies was also advanced, as the low-temperature thermal and mild solvent-based approaches were found to substantially reduce energy consumption and secondary pollution risks. Nevertheless, several key challenges remain. Removal efficiency for short-chain and weakly charged PFASs is still limited, the long-term stability of adsorbents is compromised in real wastewater matrices, large-scale production of high-performance materials remains costly, and regeneration economics and integrated technologies for simultaneous adsorbent recovery and PFAS degradation are not yet mature. Accordingly, future development should focus on the aspects such as designing multifunctional adsorbents targeting short-chain PFASs with enhanced molecular recognition and DOM resistance, coupling advanced regeneration methods (e.g., photocatalysis, electrochemical processes) with PFAS mineralization, constructing modular treatment systems adaptable to dynamic water quality, and advancing emission standards and policy incentives for green technologies. The continued evolution of adsorption technology toward higher efficiency, lower energy consumption, and integrated system design will provide a critical foundation for deep PFAS remediation in the textile dyeing industry.

Key words: textile dyeing and printing wastewater, per- and polyfluoroalkyl substance, adsorption material, adsorption mechanism, selective adsorption, wastewater treatment