Synergistic arsenic removal using chitosan-based nanocomposite beads and cross-flow ultrafiltration: A significant reduction of membrane fouling

• Published in: Journal of environmental chemical engineering 2023-04, Vol.11 (2), p.109431, Article 109431
• Main Authors: Rawat, Shweta, Chaudhary, Mohit, Maiti, Abhijit
• Format: Article
• Language: English
• Subjects: Arsenic; Chitosan beads; Combined adsorption-membrane process; Iron oxyhydroxide adsorbent; Ultrafiltration
• ISSN: 2213-3437
• DOI: 10.1016/j.jece.2023.109431

Hybrid adsorption-membrane processes provide a suitable alternative for treating large volumes of arsenic-contaminated water by combining the specificity of adsorption with the membrane process’s flexibility in terms of scale-up. The performance of such processes, with respect to removal efficiency and effluent flow rate, largely depends on the characteristics of the adsorbent used. In the present study, we have evaluated the use of in-situ precipitated iron oxyhydroxide chitosan beads (IICB) in combination with cross-flow Ultrafiltration (UF) for the treatment of arsenic-contaminated water. The performance of the combined adsorption-UF process was assessed at three different TMP (0.2–0.6 MPa). Combined Hermia’s model modified for cross-flow UF was found to be a good fit for permeate flux profiles of contaminated groundwater treated using the IICB-UF process. The effect of adding IICB on membrane fouling was evaluated using the resistance-in-series model and XDLVO theory (through contact angle measurements). For arsenic-spiked groundwater, at a dose of 2 g/L IICB, the combined UF process could bring down arsenic to permissible limits ( 10 µg/L.•Irreversible fouling reduces by 32 ± 2% on adding IICB (chitosan bead) to UF step.•Addition to arsenic the IICB removes the hydrophobic fraction of organic matter.