Adsorption equilibrium studies were evaluated at room temperature (30 ± 1 °C) using different initial concentrations of iron ranging from 5 mg/L to 25 mg/L as follows: A 100 mg of each synthetic Na-A zeolite was added to 100 ml of 5, 10, 15, 20 or 25 mg/L of iron in different plastic tubes and mixed for 6 h on a shaker at room temperature. The pH values of the solutions were adjusted to pH 3by adding either 0.1 N Sodium hydroxide or 0.1 N Nitric acid solutions. In acidic pHs, Fe(II) remains with the positive charge, but in alkali pHs, the hydroxide ions (OH−) causes precipitation of Fe(II) in the form of Fe(OH)2[9]. After equilibration, the suspensions were filtered with 45 μ membrane filters to separate solids and solutions and then, the solutions were collected in clean vials for analysis. All experiments of isotherms were carried out using triplicates. The concentrations of iron in all solutions were determined by using inductively coupled plasma mass spectrometry