Mn(II) recovery from aqueous systems by flotation

Various aqueous systems produced by different technologies can contain Mn(II) in the concentration range of 50÷1000 mg×l−1, which represents a pollution source but also can be used for the separation–recovery of useful compounds. The present paper presents the results of the researches concerning Mn(II) recovery from “model” and real aqueous systems by the precipitate flotation method, dissolved air flotation (DAF) variant, with izoalkylcarboxillic acid as collector. The following influencing factors were studied: pH, collector concentration, metallic ion concentration, necessary gas flow and foam processing with Mn(II) recovery as oxide. The separation mechanism by the collector–Mn(II) interaction at optimal conditions is also studied. Therefore, a correlation of chemical analysis results with electronic and vibrational spectra and thermal analysis is made. The results of the experimental data plead for the recovery separation of Mn(II) from aqueous systems and its recovery as oxide after thermal decomposition of the species contained in the foam.