Nano magnetite assisted flocculation for efficient harvesting of lutein and lipid producing microalgae biomass

Anil Kumar Patel; Prashant Kumar; Chiu-Wen Chen; Vaibhav Sunil Tambat; Thanh-Binh Nguyen; Chih-Yao Hou; Jo-Shu Chang; Cheng-Di Dong; Reeta Rani Singhania

doi:10.1016/j.biortech.2022.128009

Nano magnetite assisted flocculation for efficient harvesting of lutein and lipid producing microalgae biomass

Bioresour Technol. 2022 Nov:363:128009. doi: 10.1016/j.biortech.2022.128009. Epub 2022 Sep 23.

Authors

Anil Kumar Patel¹, Prashant Kumar², Chiu-Wen Chen³, Vaibhav Sunil Tambat², Thanh-Binh Nguyen², Chih-Yao Hou⁴, Jo-Shu Chang⁵, Cheng-Di Dong⁶, Reeta Rani Singhania⁷

Affiliations

¹ Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Centre for Energy and Environmental Sustainability, Lucknow-226 029, Uttar Pradesh, India.
² Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan.
³ Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Sustainable Environment Research Center, National Kaohsiung University of Science and Technology, Kaohsiung City-81157, Taiwan.
⁴ Department of Seafood Science, National Kaohsiung University of Science and Technology, No.142, Haijhuan Rd., Nanzih District, Kaohsiung City 81157, Taiwan.
⁵ Department of Chemical and Materials Engineering, Tunghai University, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Taiwan.
⁶ Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Sustainable Environment Research Center, National Kaohsiung University of Science and Technology, Kaohsiung City-81157, Taiwan. Electronic address: cddong@nkust.edu.tw.
⁷ Centre for Energy and Environmental Sustainability, Lucknow-226 029, Uttar Pradesh, India; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Sustainable Environment Research Center, National Kaohsiung University of Science and Technology, Kaohsiung City-81157, Taiwan.

PMID: 36162780
DOI: 10.1016/j.biortech.2022.128009

Abstract

For commercial scale algal biorefining, harvesting cost is a major bottleneck. Thus, a cost-effective, less-energy intensive, and efficient harvesting method is being investigated. Among several harvesting methods, magnetic flocculation offers the benefits of modest operation, energy savings and quick separation. This study aims to develop novel magnetite-(Fe₃O₄) nanoparticles (MNPs) of 20 nm average size and their high reusability potential to reduce the harvesting cost of microalgae biomass. The MNPs were synthesized and characterized using FTIR, Zeta analyzer, and SEM before performing on Chlorella sorokiniana Kh12 and Tu5. For maximum harvesting efficiency >99%, the optimal culture pH, MNPs concentration, and agitation speed were 3, 200 mg/L, and 450 rpm, respectively. Subsequently, MNPs were recovered via alkaline treatment and reused up to 5 cycles as they retained their reactivity and harvesting efficiency. The studied MNPs-based harvesting method could be adopted at a commercial scale for cost-effective algae biorefinery in the future.

Keywords: Flocculation; Harvesting; Magnetite; Microalgae; Nanoparticle.

MeSH terms

Biomass
Chlorella*
Ferrosoferric Oxide
Flocculation
Lipids
Lutein
Microalgae*

Substances

Lipids
Lutein
Ferrosoferric Oxide