Removal of molybdenum from MnSO4 solution with freshly precipitated nascent Mn3O4

The scavenging of molybdenum from MnSO4 Solution with freshly precipitated nascent Mn3O4 is reported. Firstly, nascent Mn3O4 was prepared from MnSO4 solution by adding NaOH and aerating. The aeration time had a significant influence on the preparation of nascent Mn3O4, but other factors such as pH and ageing time had little effect. SEM, XRD, particle size and surface area analysis were used to characterize nascent Mn3O4. A study was then carried out on the effects of time, concentration of Mn, initial pH, temperature and dosage of nascent Mn3O4 on the adsorption of Mo from MnSO4 solution. The results showed that the concentration of Mo in 70-200 g L-1 MnSO4 at pH 1-3 could be reduced from about 1 mg L-1 to less than 0.015 mg L-1 in 30 min at 80 degrees C by the addition of about 0.3 gL(-1) nascent Mn3O4 in suspension. Accordingly, the removal capacity of nascent Mn3O4 can reach 4.42 mg Mo/g Mn3O4. This Mo removal exceeds the requirement for special electrolytic MnO2 used in the production of alkaline zinc-manganese batteries. (C) 2009 Elsevier B.V. All rights reserved.