“Ion Ionescu de la Brad” University of Agricultural Sciences and Veterinary Medicine, Iași
Abstract
Determination of the adsorption coefficient is essential for all retention processes of ionic species on surfaces, to determine the process efficiency and influence of the various factors on the adsorption. Calcium ions are present in significant quantities in many natural waters, causing high values of hardness, implicitly restricting the possibilities of using these waters. Decreasing the content of ionic calcium from aqueous solutions can be done by retaining them on cation exchangers, soin the present paperwe chose a sulphonic resin -Dowex 50-to study the calcium adsorption from aqueous solutions of different concentrations. We determined both the values of the adsorption coefficient over time for each concentration in the dynamic process as well as the correlation between the amount of ion in the initial solution and that retained on the surface of the adsorbent, depending on the amount of resin used
