Custom-designed 3D printed feed spacers and TFN membranes with MIL-101(Fe) for water recovery by forward osmosis

ABSTRACT

In this work, a dual-pronged approach– (i) novel thin-film nanocomposite polyether sulfone (PES) membrane with MIL-101 (Fe) and (ii) 3D printed spacers were explored to enhance water recovery by forward osmosis. The concentration of PES, pore former, draw solution, and MIL-101(Fe) was optimised for maximum pure water flux (PWF) and minimum specific reverse solute flux (SRSF). The best membrane exhibited a PWF of 7.52 Lm⁻²h⁻¹ and an SRSF of 0.33 ± 0.03 gL⁻¹ using 1.5 M NaCl and DI water feed. The M₂₂ membrane with the diamond-type spacer demonstrated a PWF of 2.53 Lm⁻²h⁻¹ and SRSF of 0.75 gL⁻¹ for emulsified oily wastewater feed. The novel spacer design imparted significant turbulence to the feed flow and a lower foulant resistance of 1.3 m⁻¹ as compared to the ladder type (1.5 m⁻¹) or commercial spacer (1.7 m⁻¹). This arrangement could recover 19% pure water within 12 h of operation (98% oil rejection) with a ∼ 94% flux recovery after hydraulic wash.

GRAPHICAL ABSTRACT

KEYWORDS:

• Thin-film nanocomposite membrane
• MIL-101(Fe): 3D printed feed spacer
• oily water
• forward osmosis

Acknowledgment

The authors gratefully acknowledge the financial assistance provided to Noel Jacob Kaleekkal by the MHRD-SPARC Project (SPARC/2018-2019/P530/SL).

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article [and/or] its supplementary materials.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors gratefully acknowledge the financial assistance provided to Noel Jacob Kaleekkal by the MHRD-SPARC Project (Scheme for Promotion of Academic and Research Collaboration (SPARC)) (SPARC/2018-2019/P530/SL).