Adsorption of iron(III)-cyanide complex ions to granular activated carbon

The adsorption of iron(III)-cyanide complex anions to granular activated carbon was investigated. The iron(III)-cyanide complex ion binding capacity of the adsorbent was shown as a function of initial pH, initial iron(III)-cyanide complex ion and adsorbent concentrations. The results indicated that a significant reduction of iron(III)-cyanide complex ions was achieved at pH 13.0, a highly alkaline condition. The equilibrium loading capacity of adsorbent was 410.0 mg/g at 1255.0 mg/l initial iron(III)-cyanide complex ion concentration at this initial pH value. The Freundlich, Langmuir and Redlich-Peterson adsorption models were fitted to the equilibrium data at pH 3.0, 7.0 and 13.0. The equilibrium data could be best fitted to the Langmuir and Redlich-Peterson adsorption models over the entire concentration range at all the studied initial pH values.