Heteroflocculation of kaolin pre-treated with oppositely charged polyelectrolytes
2000 (English)In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, Vol. 164, no 2-3, 131-141 p.Article in journal (Refereed) Published
Heteroflocculation studies of kaolin particles have been carried out by mixing two kaolin suspensions; one stabilised by a cationic polymer and the other stabilised by a highly charged and low molecular weight anionic polymer. Molar mass and charge density of cationic polymer as well as the mixing ratio of oppositely charged suspensions were varied. Flee size and degradation during shearing were investigated by measuring hoc size using a light scattering/diffraction method at different flow rates. It was observed that floc size was small when subjected to a low flow rate and decreased with increasing how rate. Cationic polymers with high molar mass and low charge density produced flocs with high resistance towards flee degradation. Maximum flee size was obtained at a mixing ratio where the flocs became slightly negatively charged. Flee size and degradation were observed to be independent of primary kaolin particle size. Furthermore, floc size increased with increasing ionic strength. Scanning electron micrographs showed flocs with an open structure, which is expected to improve the optical properties of paper when using microflocs as a filler in paper production.
Place, publisher, year, edition, pages
2000. Vol. 164, no 2-3, 131-141 p.
heteroflocculation, kaolin, microflocs, floc size, floc strength, cationic polymers, sodium polyacrylate, controlled flocculation, small particles, cationic polyacrylamides, clay suspensions, molar mass, adsorption, polymer, polyethylenimine, stability
IdentifiersURN: urn:nbn:se:kth:diva-19589ISI: 000085585900005OAI: oai:DiVA.org:kth-19589DiVA: diva2:338281
QC 201005252010-08-102010-08-10Bibliographically approved