Interaction of radium with freshwater sediments and their mineral components Pt. 3

Radiotracer method was used to investigate adsorption and desorption of traces of radium on muscovite and feldspar (albite) under conditions similar to those prevailing in waste and surface waters. The effects of pH, liquid to solid ratio, time, ionic strength (Nasup(+)) and presence of Casup(2+) or SOsub(4)sup(2-) ions were studied. It was concluded that both minerals can significantly affect the fate and migration of radium in surface waters if present as major components of bottom sediments or as suspended solids in concentrations of several milligrams per liter or higher. Muscovite can adsorb radium even from moderately acidic waters. Radium adsorbed on muscovite and albite can not be easily released upon an increase of the salinity of ambient water. However, almost complete desorption can be achieved with 1M HCl. Mechanisms of radium adsorption on both minerals and character of the adsorption sites are discussed. (author)