Nanofibrous Kevlar Hydrogel Ultrafiltration Membrane with High Acid Resistance and Antifouling Properties for Wastewater Treatment

Abstract

Membrane fouling and acidic environment instability are inevitable problems restricting the widespread application of membranes in wastewater treatment. Herein, we report a polyelectrolyte hydrogel membrane with high acid resistance and antifouling properties synthesized by phase inversion of Kevlar nanofibers solution. The hydrogel membrane, compared to the commercial PVDF membrane, has a higher rejection of Congo Red, Direct Red 23, and Direct Red 80 solutions, and excellent antifouling performance when filtering bovine serum protein or humic acid solution. The high antifouling performance is attributed to a large number of hydrophilic groups in the structure of the hydrogel, which can induce the formation of a protective layer of hydration, thus reducing the pollutants adsorbed on the surface. Besides, the acid resistance ability of the Kevlar membrane was verified by a phosphoric acid (pH = 0) immersion experiment. Due to the superior performance of this membrane and the onestep preparation process, the developed Kevlar membrane has great potential applications for wastewater treatment.

Bio-Inspired Underwater Superoleophobic Aramid Nanofiber-Based Aerogel Membranes for Highly Efficient Removal of Emulsified Oils and Organic Dyes

“…Moreover, the vibration of Ph–N showed a peak at 1319 cm –1 . Therefore, the chemical composition of the prepared ANFs through deprotonation stripping was in consistent with that of reported ANFs previously. ,, …”

“…Therefore, the chemical composition of the prepared ANFs through deprotonation stripping was in consistent with that of reported ANFs previously. 26,32,47 To verify the chemical structure and composition variations of the membrane during the fabrication process, ATR-FTIR, XPS, and EDS measurements were performed, respectively. Figure 2a presents the ATR-FTIR spectra of the ANFs aerogel membrane, PDA@ANFs aerogel membrane, and CS&PDA@ ANFs aerogel membrane.…”

Diffusion-Limited Processes in Hydrogels with Chosen Applications from Drug Delivery to Electronic Components

“…The small mesh size in hydrogels greatly enhances the influence of intermolecular interactions, and simple modification of the polyacrylonitrile polymer network with hydrophilic sodium polyacrylate parts leads to a tremendous rise in filtration selectivity for organic molecule removal [74]. Compared to classic surface-active membranes, macroscopic sizes of hydrogel-based membranes and interaction areas comodifying a core network with acid-resisting Kevlar fibers do not lead to sensitivity drop but dramatically enhance such a membrane's utility [75]. Incorporating a self-healing agent into a selective hydrogel for water/organic splitting did not decrease the splitting selectivity [76].…”

Electrically Conductive PVDF Ultrafiltration Membrane with In Situ Formation of a Ag NP Coating Layer for Perm-Selectivity Enhancement and Fouling Mitigation

“…Membrane separation is an efficient green water treatment technology that offers various potential applications in water and wastewater treatments due to its easy operation, high efficiency, low energy consumption, and minimal environmental impact. − However, the selectivity–permeability “trade-off” effect and membrane fouling are two main drawbacks restricting its large-scale applications . Extensive studies have been dedicated to enhancing the hydrophilicity of membranes to reduce the water transmission resistance and prevent the accumulation of hydrophobic contaminants on the surface. , In addition, coupling an electric field with membrane filtration was also an effective approach to improve the water flux and enhance pollutant rejection. , Electrostatic repulsion between the membrane and the foulants can help mitigate membrane fouling using typical foulants such as bacteria, polysaccharides, and natural organic matter (NOM), which usually possess a negative surface charge. , The enhanced repulsive force is prone to yielding a higher rejection against pollutants and mitigating membrane fouling . Therefore, the interaction force between foulants and the membrane is a critical factor to enhance the separation and antifouling performance.…”

“…4 Extensive studies have been dedicated to enhancing the hydrophilicity of membranes to reduce the water transmission resistance and prevent the accumulation of hydrophobic contaminants on the surface. 5,6 In addition, coupling an electric field with membrane filtration was also an effective approach to improve the water flux and enhance pollutant rejection. 7,8 Electrostatic repulsion between the membrane and the foulants can help mitigate membrane fouling using typical foulants such as bacteria, polysaccharides, and natural organic matter (NOM), which usually possess a negative surface charge.…”