Surface-induced electrolytic dissociation of weak acids in ethanol

Abstract

Positively charged particles of metal oxides (alumina, hematite, and titania) enhance the electrolytic dissociation of phosphoric, oxalic, citric, and succinic acids in 94% ethanol (by mass). This results in enhanced electric conductance of dispersions of these oxides, which is higher than the conductance of dispersion containing only solvent and metal oxide and of an alcoholic solution of a weak acid. This phenomenon is accompanied by a shift of the ζ potential of the oxide particles to more negative values. The changes in the ζ potential indicate strong positive adsorption of anions from solution. © 2010 American Chemical Society.