News Picture Generic

Flocculation behavior and mechanisms of block copolymer architectures on silica microparticle and Chlorella vulgaris systems

September 22, 2020

Journal of Colloid and Interface Science

Hypothesis

Flocculation performance using polyelectrolytes is influenced by critical design parameters including molecular weight, amount and sign of the ionic charge, and polymer architecture. It is expected that systematic variation of these characteristics will impact not only flocculation efficiency (FE) achieved but that charge density and architecture, specifically, can alter the flocculation mechanism. Therefore, it should be possible to tune these design parameters for a desired flocculation application.

Experiments

Cationic-neutral and polyampholytic copolymers, exhibiting a range of molecular weights (103–106 g/mol), varying charge levels (0–100% cationic, neutral and anionic), and random or block copolymer architecture, were applied to dilute suspensions of silica microparticles (control) and Chlorella vulgaris. FE and zeta potential values were determined over a range of flocculant doses to evaluate effectiveness and mechanism achieved.

Findings

These different classes of copolymers provide specific benefits for flocculation, with many achieving >95% flocculation. Block copolymer flocculants exhibit a proposed, dominant bridging mechanism, therefore reducing flocculant dosage required for effective flocculation when compared to analogous random copolymer flocculants. Polyampholytic copolymers applied to C. vulgaris generally exhibited a bridging mechanism and increased FE compared to equivalent cationic-neutral copolymers, indicating a benefit of the anionic component on a more, complex, diversely charged suspension.

For details

Flocculation behavior and mechanisms of block copolymer architectures on silica microparticle and Chlorella vulgaris systems

Kathryn L. Morrissey a, Benjamin D. Fairbanks a, David S. Bull a, Mark P. Stoykovich b, Christopher N. Bowman a

a Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, CO 80309, USA

b Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA

For more information about Chemspeed solutions:

ISYNTH

SWING SP

Journal of Colloid and Interface Science
https://doi.org/10.1016/j.jcis.2020.02.001
© 2020 Elsevier Inc. All rights reserved.

For details please contact [email protected]

Other Recent News

Discover more news articles you might be interested in

Read more about High-throughput solid microsampling through stochastic robotic automation
News Picture 1 1 V2
Featured
Jul
14

High-throughput solid microsampling through stochastic robotic automation

Solid sampling at the sub-milligram and milligram scale remains a major bottleneck for high-throughput chemistry or material sciences, as existing approaches rely on manual handling or slow deterministic microsampling that do not readily scale.

Here we present STORMS, an automated STOchastic Robotic MicroSampling system that enables fast, reliable and parallel sampling of solid materials at sub-milligram and milligram masses. 

Read more about Parameter efficient multi-model vision assistant for polymer solvation behaviour inference
News Picture 1 1 V2
Jun
30

Parameter efficient multi-model vision assistant for polymer solvation behaviour inference

Polymer–solvent systems exhibit complex solvation behaviours encompassing a diverse range of phenomena, including swelling, gelation, and dispersion. Accurate interpretation is often hindered by subjectivity, particularly in manual rapid screening assessments. While computer vision models hold significant promise to replace the reliance on human evaluation for inference, their adoption is limited by the lack of domain-specific datasets tailored, in our case, to polymer–solvent systems.

© Chemspeed (part of Bruker) 2026