Influence of MII/MIII ratio in surface-charging behavior of Zn–Al layered double hydroxides

RICARDO ROJAS; CARLOS PRIMO DE PAULI; CRISTOBALINA BARRIGA; MARCELO J. AVENA

APPLIED CLAY SCIENCE

Elsevier

Lugar: Amsterdam; Año: 2008 vol. 40 p. 27 - 27

0169-1317

font face="AdvTT6120e2aa" size="1"> Zn–Al layered double hydroxides with different MII/MIII ratios were synthesized by the coprecipitation method and the obtained solids were characterized by powder X-ray diffraction, infrared spectroscopy, acid–base potentiometric titrations, electrophoretic mobility and modeling of the electrical double layer. As general behavior, increasing hydroxyl adsorption with increasing pH and decreasing supporting electrolyte concentration takes place between pH 7 and 12. The electrophoretic mobility of the samples are in all cases positive and it decreases when the pH becomes higher than 9. A net positiv