Abstract
This study included different soil locations around Mosul city representing non salt affected soils, and around Basrah city representing salt – affected soil. The aim of this study is to show the behavior of sodium due to first order and diffusion equations, using miscible displacement at different times (10, 20, 30, 60, 90, 120, 180, 360, 480, 600, 720 minute). The results indicate that the solubility and release of sodium decreases with time, but according to kinetic concept the cumulative of sodium solubility increased in the two type of soils study. However, salt affected soils showed more solubility and release of sodium than the non-salt affected soils. While the diffusion equation gave the best description of sodium solubility depending on the coefficient determination and standard error. Selectivity coefficient of Gapon due to the chemical concept KG, thermodynamic concept KG- and sposito concept KG= were also examend which showed that the values KG , KG- decreased with time , while KG= values increased over time.
