Transport and Adsorption-Desorption of Silver in Soils.

The objective was to qualify adsorption-desorption behavior and transport of silver in soils having different properties. This study also investigated the influence of the presence of Zn on silver retention and transport in soils. Kinetic batch adsorption-desorption column experiments were carried out to investigate the adsorption-desorption and transport of silver in three different soils in the presence of Zn. For all soils, results indicated that adsorption isotherms for Ag were highly nonlinear with greater affinity for the Webster soil. The presence of Zn resulted in reduced Ag sorption indicative of competitive behavior.  Transport of Ag was carried out miscible-displacement in saturated soil columns.  Measured breakthrough results (BTCs) from of highest Ag mobility in Olivier whereas Webster soil exhibited least mobility among the three soils.  This finding is based on the Ag recovered in the effluent solution and the retardation of the BTCs. Furthermore, the presence of Zn resulted in enhanced mobility of Ag.