Radioanalytical monitoring of the formation of barium sulfate in aqueous solutions

The process of spontaneous precipitation of barium sulphate from aqueous solutions was investigated. Possible mechanisms for the formation of barium sulphate when the supersaturation of the solution changed were examined. Radioactive barium was used to prepare the supersaturated solutions to maximize accuracy in monitoring the precipitation process. Rates of precipitation were measured accurately and values were obtained for such parameters as the size of the critical nucleus and the surface energy of the precipitate. Kinetic parameters such as induction times and rates of precipitation were used to elucidate nucleation and crystal growth processes.