Effect of phosphate and polyphosphonates on the dissolution of barium fluoride

Abstract

The inhibiting effect of phosphate and a number of selected phosphonates on the dissolution rate of barium fluoride crystals in aqueous solutions has been investigated using a constant composition method at 25 °C. The presence of phosphate, even at relatively low concentrations, reduced the rates of dissolution while dissolution reactions were markedly inhibited by addition of phosphonate. The influence of the additive on barium fluoride dissolution reactions could be interpreted in terms of a Langmuir-type adsorption isotherm. The kinetically derived adsorption affinities are compared with the directly measured adsorption equilibrium constants.