Anhydrous volatile fatty acid extraction through omniphobic membranes by hydrophobic deep eutectic solvents: Mechanistic understanding and future perspective
Document Type
Article
Publication Date
6-15-2024
Abstract
Volatile fatty acids (VFAs) derived from arrested anaerobic digestion (AD) can be recovered as a valuable commodity for value-added synthesis. However, separating VFAs from digestate with complex constituents and a high-water content is an energy-prohibitive process. This study developed an innovative technology to overcome this barrier by integrating deep eutectic solvents (DESs) with an omniphobic membrane into a membrane contactor for efficient extraction of anhydrous VFAs with low energy consumption. A kinetic model was developed to elucidate the mechanistic differences between this novel omniphobic membrane-enabled DES extraction and the previous hydrophobic membrane-enabled NaOH extraction. Experimental results and mechanistic modeling suggested that VFA extraction by the DES is a reversible adsorption process facilitating subsequent VFA separation via anhydrous distillation. High vapor pressure of shorter-chain VFAs and low Nernst distribution coefficients of longer-chain VFAs contributed to DES-driven extraction, which could enable continuous and in-situ recovery and conversion of VFAs from AD streams.
Identifier
85191898968 (Scopus)
Publication Title
Water Research
External Full Text Location
https://doi.org/10.1016/j.watres.2024.121654
e-ISSN
18792448
ISSN
00431354
PubMed ID
38701552
Volume
257
Grant
2023-79000-38973
Fund Ref
U.S. Department of Energy
Recommended Citation
Zhang, Xueyao; Wang, Jiefu; Zhang, Yuxuan; Qing, Weihua; Lansing, Stephanie; Shi, Jian; Zhang, Wen; and Wang, Zhi Wu, "Anhydrous volatile fatty acid extraction through omniphobic membranes by hydrophobic deep eutectic solvents: Mechanistic understanding and future perspective" (2024). Faculty Publications. 344.
https://digitalcommons.njit.edu/fac_pubs/344
