Nanoscale Evidence Unravels Microalgae Flocculation Mechanism Induced by Chitosan

In this work, a novel cationic polyacrylamide (PAMD) was synthesized by acrylamide (AM) diallyl dimethyl ammonium chloride (DMD) and dodecyl polyglucoside (DPL) under low-pressure ultraviolet (UV) initiation. The intrinsic viscosity and cationic degree of PAMD were optimized in copolymerization. The optimum synthesis conditions that affect polymerization were determined to be solid content 30%, DPL content 25%, DMD content 30%, illumination time 135 min, and pH 9. The flocculation performance of flocculant PAMD with a high cationic degree was investigated in the purification of high-turbidity water. The flocculation mechanism was correspondingly studied and summarized based on Fourier transform-infrared (FTIR) analysis. Finally, the results of an experimental simulation using the response surface method show that 98.9% supernatant transmittance was achieved under dosage 4 mg/L, fast stirring time 20 min, pH 7, and stirring speed 320 rpm.

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Research on self-degradation of RGO/TiO2-P(AM-DAC) organic-inorganic composite flocculant prepared by surface initiated polymerization and its flocculation mechanism of oil sand tailings

European Polymer Journal ◽

10.1016/j.eurpolymj.2019.07.040 ◽

2019 ◽

Vol 120 ◽

pp. 109165 ◽

Cited By ~ 7

Author(s):

Haiwang Wang ◽

Yukai Zhang ◽

Dekuan Gao ◽

Guanqi Wang ◽

Yuan Ma ◽

...

Keyword(s):

Oil Sand ◽

Flocculation Mechanism ◽

Surface Initiated Polymerization ◽

Inorganic Composite

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Pre-concentration of microalga Euglena gracilis by alkalescent pH treatment and flocculation mechanism of Ca3(PO4)2, Mg3(PO4)2, and derivatives

Biotechnology for Biofuels ◽

10.1186/s13068-020-01734-8 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Mingcan Wu ◽

Jing Li ◽

Huan Qin ◽

Anping Lei ◽

Hui Zhu ◽

...

Keyword(s):

Euglena Gracilis ◽

Flocculation Mechanism

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Research on the coagulant aid effects of modified diatomite on coal microbial flocculation

Water Science & Technology ◽

10.2166/wst.2020.009 ◽

2019 ◽

Vol 80 (10) ◽

pp. 1893-1901

Author(s):

Dong Jingshen ◽

Liu Quanjun

Keyword(s):

Zeta Potential ◽

Good Effect ◽

Coal Slurry ◽

Single Factor ◽

Flocculation Mechanism ◽

Microbial Flocculant ◽

Flocculation Effect ◽

Chitosan Molecule ◽

Modified Diatomite ◽

Microbial Flocculation

Abstract Diatomite was modified by chitosan to prepare modified diatomite, and the modified diatomite in an optimized ratio was utilized in coal bio-flocculation. The interaction behavior and flocculation mechanism of modified diatomite on coal slurry water were investigated by single factor experiments, infrared spectroscopy, Brunauer-Emmett-Teller (BET) measurements, and zeta potential measurements. The single factor experiments showed that when the amount of microbial flocculant added was 1.5 ml, the temperature of coal slurry water was 39 °C, the pH was 5, and the amount of modified diatomite was 0.2 g, after 30 min of sedimentation, the flocculation transmittance of the coal slurry water reached 84.3%. The infrared spectra showed that the -NH2 and -OH of the chitosan molecule had a polar interaction with the Si-OH bond in diatomite. The BET measurements showed that the specific surface area of diatomite was not a decisive factor affecting the flocculation effect. Zeta potential measurements indicated that the amino protonation of chitosan increased the isoelectric point (IEP) of modified diatomite. These results showed that modified diatomite has a good effect on coal bio-flocculation.

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