Adsorption of polyamine on clay minerals

• Published in: Journal of colloid and interface science Vol. 336; no. 2; pp. 599 - 606
• Main Authors: Blachier, C., Michot, L., Bihannic, I., Barrès, O., Jacquet, A., Mosquet, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 15.08.2009; Elsevier
• Subjects: Adsorption; Charge; Chemistry; Clay; Clay minerals; Colloidal state and disperse state; Continental interfaces, environment; Environmental Sciences; Evolution; Exact sciences and technology; Flocculating; Flocculation; General and physical chemistry; Global Changes; Infrared spectroscopy; Isotherms; Montmorillonite; Polycation; SAXS-WAXS; Sciences of the Universe; Surface chemistry; Surface physical chemistry; Zeta potential; Clay; Infrared spectroscopy; Polycation; Adsorption; Zeta potential; Flocculation; SAXS-WAXS; Stacking; Illite; Adsorption isotherm; Small angle X ray scattering; Powder; Wax; Particle; Electrokinetic potential; Kaolinite; Structure; Cation exchange; Surface charge; Polyamine; Montmorillonite; Polymer; Suspension; X ray diffraction; Infrared spectrometry; Amine polymer; Reflectance
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2009.04.021

Cationic exchange plays a major role in the adsorption of polyamine onto clays, leading to the flocculation of clay suspensions when particles reached a zero charge. This work aims at a better understanding of the interaction between a polycationic quaternary amine polymer (F25) and three different clay minerals: montmorillonite, illite, and kaolinite. For this, adsorption isotherms of F25 on the clay surfaces were measured together with the evolution of the CEC along the isotherm, which revealed that cation exchange plays an important role in the adsorption process. These first results were confirmed by XRD measurements on dried powders that are evidence in the case of montmorillonite of the presence of polymer in the interlayer spaces. In addition, the evolution of the short range structure of clay minerals suspensions on polymer adsorption was followed by WAXS experiments. Polymer intercalation was observed while the structure of the resulting stacking appeared to change slightly along the polymer adsorption isotherm. Diffuse reflectance infrared measurements revealed that significant conformational changes occur on polymer adsorption onto montmorillonite surfaces. Furthermore, adsorption above the CEC is observed which involves a charge reversal of clay mineral surfaces, the zero charge being reached for an adsorbed amount corresponding to the CEC. Finally, flocculation was discussed compared to adsorption amounts and zeta potential measurements, confirming that optimum flocculation concentration is reached for noncharged particles.