Cationic flotation of iron ores: amine characterization and performance

In this investigation, the differences in the absorption spectra of etheram ines, fatty amines and condensates, mostly present as acetates, from severa l suppliers are characterized by means of infrared spectrometry. Sharp diff erences were observed in the absorption spectra of three types of amines an d derivatives. Etheramines show a characteristic and well-defined peak at 1 ,114 cm(-1). This peak is due to the ether C-O group and differentiates eth eramines from the other classes. The absence of such a peak indicates that the species is not an etheramine. The distinction between condensates and f atty amines is made by the presence of a sharppeak around 3,200 cm(-1). Thi s peak is probably due to the proximity of the N-H amine groups and C=O car bonyl groups in the amide portion. of the condensate's molecule and by diff erent and better-defined bands in the 1,800- to 1,500-cm(-1) range. The flo tation performance of these amines was evaluated by means of the laboratory -scale flotation of an itabirite ore. The etheramines proved to be the most effective collectors for this system. Monoamines presented better performa nce than diamines for the ore under investigation.