In-situ self-assembly of plant polyphenol-coated Fe3O4 particles for oleaginous microalgae harvesting

Xiaoyu Wang; Yuan Zhao; Xiaoxue Jiang; Lijun Liu; Xue Li; Huixian Li; Wenyan Liang

doi:10.1016/j.jenvman.2018.03.019

In-situ self-assembly of plant polyphenol-coated Fe₃O₄ particles for oleaginous microalgae harvesting

J Environ Manage. 2018 May 15:214:335-345. doi: 10.1016/j.jenvman.2018.03.019. Epub 2018 Mar 11.

Authors

Xiaoyu Wang¹, Yuan Zhao¹, Xiaoxue Jiang¹, Lijun Liu¹, Xue Li¹, Huixian Li¹, Wenyan Liang²

Affiliations

¹ Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
² Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China. Electronic address: lwy@bjfu.edu.cn.

PMID: 29533831
DOI: 10.1016/j.jenvman.2018.03.019

Abstract

Plant polyphenol (PP), a natural polymer from the Larix gmelinii, was selected as the surfactant to synthesize Fe₃O₄. The Fe₃O₄-PP composite was prepared by in-situ self-assembly in solvothermal synthesis, and characterized using FE-SEM, TEM, XRD, FTIR, XPS, TGA, and VSM. The harvesting efficiency of Chlorella vulgaris was investigated under different parameters, including algal organic matter, dosage, and pH. The results showed that the core-shell sphere of Fe₃O₄-PP (∼150 nm) was coated by ∼50 nm PP with a saturated magnetization of 40.0 emu/g. The Fe₃O₄-PP could be directly applied to the culture broth (1.5 g dry cell weight/L, pH = 9.03), achieving 93.0% of harvesting efficiency at 20 g/L. Cells were detached from the harvested aggregates by adjusting pH value to 9.80 and with ultrasonication, which achieved 95.6% of recovery efficiency. The recycled Fe₃O₄-PP showed high stabilities in surface properties, maintaining more than 87.5% of harvesting efficiency after five recycles.

Keywords: Chlorella vulgaris; Fe(3)O(4); In-situ; Magnetic separation; Plant polyphenol.

MeSH terms

Chlorella vulgaris*
Iron Compounds / chemistry*
Microalgae
Polymers*
Surface Properties

Substances

Iron Compounds
Polymers