Author Identifier (ORCID)
Javad Farahbakhsh: https://orcid.org/0000-0002-5032-6493
Masoumeh Zargar: https://orcid.org/0000-0001-9811-6156
Abstract
Membrane filtration has emerged as a viable technique for microalgal dewatering. However, fouling constraints limit their large-scale implementation. In this research, the fouling patterns during ultrafiltration of Chlorella sp. and Dunaliella salina were investigated using both dead-end and crossflow filtration modules. Chlorella sp. filtration in the dead-end module revealed an initial flux of 72.02 L.m−2.h−1 in the first cycle, which rapidly decreased to 19.18 L.m−2.h−1 within 30 min. In the second and third cycles, the initial flux exhibited decreases of 23 % and 50 %, respectively. Chlorella sp. demonstrated lower fouling than D. salina in a dead-end. However, in the crossflow module, D. salina maintained a consistently higher flux compared to Chlorella sp. Across both configurations, Chlorella sp. caused greater irreversible fouling (22 % in dead-end, 13 % in crossflow) than D. salina (8 % and 7 %, respectively), likely due to higher organic molecule production by Chlorella sp. SEM micrographs revealed a gradual cake layer buildup on membrane surfaces despite backwashing, and FTIR spectroscopy confirmed the presence of microalgal functional groups post-backwash, highlighting cake resistance as the dominant fouling mechanism. Flux significantly improved as the transmembrane pressure (TMP) increased, while flocculation with 100 mg.L−1 FeCl3 yielded the best results. Although a higher pH slightly improved the initial flux, the overall effect of pH was minimal. These findings highlight that ultrafiltration harvesting of microalgae could be greatly improved through transmembrane pressure (TMP) optimization and flocculation as effective strategies for enhancing filtration efficiency.
Document Type
Journal Article
Date of Publication
10-1-2025
Volume
78
Publication Title
Journal of Water Process Engineering
Publisher
Elsevier
School
School of Engineering
RAS ID
88211
Funders
Forrest Research Foundation
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Mkpuma, V. O., Najafi, M., Farahbakhsh, J., Zargar, M., Moheimani, N. R., & Ennaceri, H. (2025). Membrane fouling dynamics and flux optimization in the ultrafiltration of Chlorella sp. MUR 269 and Dunaliella salina CS 744/01. Journal of Water Process Engineering, 78, 108808. https://doi.org/10.1016/j.jwpe.2025.108808