Research
| Title： | Time-Resolved Kinetic Measurement of Microalgae Agglomeration for Screening of Polysaccharides-Based Coagulants/Flocculants |
|---|---|
| First author： | Zhou, Jinxia; Jia, Yunlu; Gong, Xiaobei; Liu, Hao; Sun, Chengwu |
| Journal： | INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH |
| Years： | 2022 |
| DOI： | 10.3390/ijerph192114610 |
| Abstract： | Time-resolved monitoring of microalgae agglomeration facilitates screening of coagulants/flocculants (CFs) from numerous biopolymer candidates. Herein, a filtering-flowing analysis (FFA) apparatus was developed in which dispersed microalgal cells were separated from coagulates and flocs formed by CFs and pumped into spectrophotometer for real-time quantification. Polysaccharides-based CFs for Microcystis aeruginosa and several other microalgae were tested. Cationic hydroxyethyl cellulose (CHEC), chitosan quaternary ammonium (CQA) and cationic guar gum (CGG) all triggered coagulation obeying a pseudo-second-order model. Maximal coagulation efficiencies were achieved at their respective critical dosages, i.e., 0.086 g/g(M.a.) CHEC, 0.022 g/g(M.a.) CQA, and 0.216 g/g(M.a.) CGG. Although not active independently, bacterial exopolysaccharides (BEPS) aided coagulation of M. aeruginosa and allowed near 100% flocculation efficiency when 0.115 g/g(M.a.) CQA and 1.44 g/g(M.a.) xanthan were applied simultaneously. The apparatus is applicable to other microalgae species including Spirulina platensis, S. maxima, Chlorella vulgaris and Isochrysis galbana. Bio-based CFs sorted out using this apparatus could help develop cleaner processes for both remediation of harmful cyanobacterial blooms and microalgae-based biorefineries. |
