Premium
The role of surfactants in the flotation of molybdenite at climax
Author(s) -
Ronzio R. A.
Publication year - 1970
Publication title -
journal of the american oil chemists' society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.512
H-Index - 117
eISSN - 1558-9331
pISSN - 0003-021X
DOI - 10.1007/bf02632973
Subject(s) - molybdenite , chemistry , adsorption , molybdenum , inorganic chemistry , chemical engineering , organic chemistry , metallurgy , materials science , quartz , fluid inclusions , engineering
The use of petroleum hydrocarbon as a collector for molybdenum sulfide improved metal recovery but necessitated the investigation of surfactants to produce a suitable froth for flotation at the Climax, Colorado mill of American Metal Climax, Inc. Up to December, 1958, 346 surfactants had been tested and evaluated. A sulfated monoglyceride of coconut oil is presently employed at Climax. The study of the role of surfactants for molybdenum sulfide flotation is continuing. One of the better materials evaluated in the last 10 years is ethoxylated, esterified and neutralized lauryl alcohol. Longer and shorter chain alcohols ethoxylated, esterified and neutralized have also been evaluated with encouraging results. Adsorption of iron hydrated complexes on molybdenite occurs which results in increased wettability of the molybdenite, an effect to strongly link the molybdenite to the water phase and reduce separability. Adsorption of ionic iron on montmorillonite and other clays occurs which activates the clays for adsorption onto the molybdenite particles. In fact, a cocoon‐like coating has been found to surround molybdenite particles. This coating being highly water wettable, prevents particles of molybdenite from responding to flotation. Depression of molybdenite particulates may be caused by a “failure to collect” which is a descriptive term indicating the lack of a colector reaction at the molybdenite surfaces. For example, iron ionic complexes adsorbed at the molybdenite surface may not be reactive with the collector or the iron ions could reduce the collector concentrating by reaction in the fluid phase. Certain of the iron complexes upon adsorption onto the molybdenite may react on highly hydrated surfaces, firmly linking the particulates to the water phase. Actually, the depression of molybdenite is incompletely understood, but it is known that hydrated ionic complexes of ferrous and ferric iron are surface‐active on molybdenite. In excessive concentrations these ions could be depressive. On the other hand, limited concentration of these ions could serve as activating ions.