Corrosion of Lead Glasses in Acid Media: II, Concentration Profile Measurements

Lead concentration profiles were measured in a binary lead silicate glass corroded by acid using ahd a-backscattering technique. These profiles were characteristic of those predicted for an interdiffusion process and revealed a surface layer deficient in lead. Diffusion coefficients for Pb²⁺ were calculated, together with values of the total amount of lead removed at the various experimental temperatures and times. Good agreement was found between these data and those previously obtained experimentally. All diffusion coefficient values were high and, correspondingly, activation energy values were low compared with those predicted by the literature for similar glass compositions. This difference was justified from consideration of the leaching process.