Kinetics of Sr2+ sorption on clinoptilolite-containing tuffs of different deposits from the surface drinking water

Previously Sr2+ion-exchange isotherms were obtained from the surface drinking water and the corresponding Sr2+ distribution coefficients (Kd) were calculated for linear part of the isotherms of the studied CLT. The comparative kinetic data of Sr2+ ion-exchange sorption on NH4+- forms of the clinoptilolite-containing tuffs from deposits of Russia and Bulgaria on the sample of the surface drinking water was investigated in detail with the known method of the "thin layer". It was shown, that the kinetic process of the Sr-sorption on the clinoptilolite- containing tuffs is characterized with the features and includes 3 stages. The first stage is described with the particle diffusion law, the second stage –a slowing down, the ion-exchange process reaches a plateau, then an increase of Sr2+ sorption is observed again. The particle diffusion coefficients of Sr2+ describing the first stage of the sorption process on CLT of different deposits were calculated. The obtained data are the initial one for the development of a mathematical model of the dynamic ion-exchange process on NH4+-form of the clinoptilolite- containing tuffs from the surface drinking waters, that makes possible to generate the computer program and thereupon to calculate the break-through curves of Sr2+ sorption on NH4+- clinoptilolite- containing tuffs for the different dynamic conditions, including the sorption dynamic conditions on the permeable reactive barrier