title: Ionic dextran derivatives for removal of Fastac 10 EC from its aqueous emulsions.
abstract: Separation studies of Fastac 10 EC from model emulsions by cationic polysaccharides were followed by UV-vis spectroscopy and zeta potential measurements. Floc size measurements at the optimum polycation dose were also carried out using laser diffraction technology. The investigated polyelectrolytes contained various amounts of quaternary ammonium salt groups, N-ethyl(octyl)-N,N-dimethyl-2-hydroxypropyl ammonium chloride, attached to a dextran backbone. The effects of polycation dose, its charge density, emulsion pH and pesticide concentration on the flocculation performance were studied. The pesticide removal results (UV-vis spectroscopy) show that the optimum polycation dose decreased with increasing polymer charge density and the emulsion pH and increased with increasing pesticide concentration. The zeta potential values close to zero at the optimum polymer dose point to contribution, mainly, from charge neutralization mechanism for the flocculation process. The flocs size increase with increasing pesticide concentration was also observed.
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda, 41A, 700487 Iasi, Romania. Electronic address: lghimici@icmpp.ro.
authors.forename: Luminita
authors.initials: L
authors.lastname: Ghimici
authors.affiliation: "Petru Poni" Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda, 41A, 700487 Iasi, Romania.
authors.forename: Marieta
authors.initials: M
authors.lastname: Nichifor
mesh_terms: D002412:Cations / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D005427:Flocculation; D010575:Pesticides / Q000302:isolation & purification*; D011722:Pyrethrins / Q000302:isolation & purification*; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000032:analysis; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D002412:Cations; D003911:Dextrans; D004655:Emulsions; D010575:Pesticides; D011722:Pyrethrins; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical; C017160:cypermethrin
keywords: Cationic polysaccharide; Flocculation; Pesticide; UV–vis spectroscopy; Zeta potential