Sorption of Molybdenum in Dilute Aqueous Solutions by Activated Carbons

Molybdate in dilute aqueous solutions were treated by activated carbons. Unless otherwise stated, all the operations were carried out at 25°Cand initial concentration of ammonium molybdate and sodium molybdate were 5.0×10-3mol/l.The results in these experiments described as follows:1) Sorption of molybdate on the activated carbons varied considerably with the various types of the activated carbons. Residual molybdate in aqueous solutions reached a minimum values at pH 1.5-2.5 in the initial solution in case of any activated carbons.2) Sorption of molybdate on the activated carbons were little affected in the presence of large amount of copper ions, but they were inclined to decrease gradually with increasing ferric ions. Sorption of molybdate on the activated carbons were not affected very much even if SO42- as Na2 SO4 in the initial solution increased, within the range of molar ratio S042-/MO=about 50.3) Molybdate sorbed on the activated carbons could be eluded by alterations in pH of the solutions. lkaline solutions (NH4OH, NaOH etc) were more effective eluents for desorption of molybdate than acidic solutions (H2S04, HC1 etc).