Reflectance Spectral Characteristics of Minerals in the Mboukoumassi Sylvite Deposit, Kouilou Province, Congo

Abstract

This study presents reflectance spectra, determined with an ASD Inc. TerraSpec ® spectrometer, of five types of ore and gangue minerals from the Mboukoumassi sylvite deposit, Democratic Republic of the Congo. The spectral absorption features, with peaks at 999, 1077, 1206, 1237, 1524, and 1765 nm, of the ore mineral carnallite were found to be different from those of gangue minerals. Spectral comparison among carnallite samples from different sylvite deposits suggests that, in contrast to spectral shapes, the absorption features of carnallite are highly reproducible. Heating of carnallite to 400 and 750˝C, and comparing the spectra of heated and non-heated samples, indicates that spectral absorption is related to lattice hydration or addition of hydroxyl. Since carnallite undergoes deliquescence easily, the absorption features of carnallite in the 350-2500 nm spectrum could serve as a robust tool for carnallite identification and separation.

Improvement of sylvite flotation from halite by starvation feeding the collector octadecylamine

“…1 The K 2 SO 4 of SLNP is obtained by the conversion of sylvite (KCl) and schoenite (K 2 SO 4 $MgSO 4 $6H 2 O) with the addition of water, 2 among which sylvite is gained from a carnallite (KCl$MgCl 2 $6H 2 O)/halite (NaCl) mixed crystal product by a combination process of cold decomposition and otation. 3,4 With regard to the otation process, the main purpose is to separate sylvite from halite and obtain high grade sylvite. However, in the production process of SLNP, there is a serious problem that the Na + grade (7-9%) in sylvite concentrate is much higher than the requirement of 6%, resulting in mirabilite (Na 2 SO 4 $10H 2 O) being easily generated when the conversion of sylvite and schoenite to K 2 SO 4 is carried out, 5 which seriously decreases the quality of K 2 SO 4 .…”