Synergetic Effect of Cationic Polymer Microparticles and Anionic Polymer on Fine Clay Flocculation

• Published in: Journal of colloid and interface science Vol. 216; no. 2; pp. 409 - 417
• Main Authors: Xiao, H, Liu, Z, Wiseman, N
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15-08-1999; Elsevier
• Subjects: Applied sciences; clay suspensions; electrostatic interaction; Exact sciences and technology; flocculation; microparticle; Organic polymers; Physicochemistry of polymers; polymer; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts; polymer; electrostatic interaction; clay suspensions; flocculation; microparticle; Clay; Emulsion copolymerization; Quaternary ammonium copolymer; Styrene derivative copolymer; Experimental study; Synergism; Latex; Submicron particle; Polyelectrolyte; Methacrylamide derivative copolymer; Flocculation reagent; Flocculation; Preparation; Concentration effect; Charged particle; pH; Methacrylate copolymer; Radical copolymerization; Styrene copolymer
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1006/jcis.1999.6342

Although much research has been done into flocculation systems involving anionic microparticles, few systematic investigations employing cationic polymer microparticles (CPM) have been reported. In the present work, emulsifier-free polymerization was conducted via copolymerization of styrene with three types of cationic monomer. This technique allowed cationic polymer microparticles with well-defined structures to be prepared. Dynamic flocculation experiments showed that the effectiveness of CPM alone as a flocculant for fine clay particles is affected by CPM charge density and by particle size, in the range 0.2 to 0.4 μm. A strong synergetic effect between CPM and anionic polyacrylamide with high molecular weight and low charge density was observed. This significantly reduced the dosage of polymeric flocculant required for effective flocculation. The best flocculation occurred at a value of the anionic polymer:CPM ratio of 1:8 (wt), with anionic polymer dosage approximately 0.06 wt% on clay. Electrostatic interaction between CPM and anionic polymer appears to be an important driving force for flocculation.