Hemi-Micelle Formation – Hydrocarbon Chain Role in Alkyl Flotation Collector
The marked changes in electrokinetic potentials of quartz in dodecylammonium acetate (DDA) solutions were postulated to result from the association of adsorbed collector ions into two-dimensional aggregates, called hemi-micelles. The rapid increase in flotation rate of quartz was shown to coincide with hemi-micelle formation. Micelle Hypothesis In dilute solutions alkyl ammonium and related salts behave […]
Copper Activation Sphalerite & Xanthate
Copper Activation Sphalerite & Xanthate: Unlike most other sulfide minerals, sphalerite responds poorly to short-chain thiol collectors. The problem is attributed to the high solubility of zinc-thiol compounds in water. Also, due to its large band gap (3.7 eV), sphalerite is a poor catalyst for mixed potential reactions between xanthate and oxygen. The reactivity of […]
Gold Pyrite, Pyrrhotite and Arsenopyrite Recovery
One of the more common classes of ores containing gold is when gold is associated with pyrite, pyrrhotite, and arsenopyrite. This is the area of gold recovery that has probably received the most research and plant optimization support especially in light of the long history of South African industrial practice. From a reagent viewpoint, charged […]
Recover Ultrafine Chalcopyrite by Flotation
Froth flotation is used almost universally in the beneficiation of base metal sulfide ores. Although flotation is very efficient for particles between 150 and 10 µm in size, this efficiency drops off rapidly, as the particle sizes drop below 10 µm. Significant quantities of these ultrafine sulfide values are lost in the beneficiation of copper […]
Effect of Column Flotation Bubble Size
Bubble Size The most important physical aspect of flotation is bubble size. While most people agree that small bubbles are needed for good flotation, what is meant by “small bubbles?” We have always maintained that the bubbler is the heart of the column and have spent many years developing our bubbler to its present state. […]
Is Oleic Acid Or Oleoyl Sarcosine more Selective in the Flotation of Salt Type Minerals
Oleic acid has been almost invariably used in the flotation of siliceous fluorite ores. The performance of oleic acid, however, deteriotates with carbonaceous fluorite ores. Oleoyl sarcosine developed recently has been found to produce results superior over oleic acid with ores containing high calcite contents. While the mechanism of oleate adsorption is usually considered as […]
Flotation of Silver Bearing Minerals from Sulfide Ores
Silver is an economically important component of many complex, massive sulfide ores, and often is produced as a byproduct during recovery of base metals from sulfide deposits. About two-thirds of the world’s silver resources are contained in base-metal sulfide deposits (Reese, 1991). These ores are beneficiated almost exclusively by flotation. Silver recovery during flotation, however, […]
Column Flotation for Copper: Techniques and Advantages
A column flotation system was designed to conduct release analyses of a very finely disseminated, stratiform, copper ore from the Denali Copper Prospect, Alaska. Chalcopyrite is finely disseminated in a carbonate matrix and pyrite is disseminated in both the chalcopyrite and gangue, requiring grinding to 20 microns for adequate liberation. The ore is almost entirely […]
Adsorption Behavior of Oleate
The adsorption behavior of sodium oleate on brucite, Mg(OH)2, has been studied by Fourier transform infrared spectroscopy. Both internal reflection and diffuse reflection (DRIFT) methods were used to characterize the adsorbed oleate on brucite. DRIFT measurements were shown to be quantitative, and an equilibrium adsorption isotherm was obtained. The conformational behavior of the adsorbed oleate […]
Laboratory Baffled-Column Flotation
The separating efficiency of a flotation column is largely limited by the degree of backmixing of tailings into the froth zone, and its recovery is limited by the degree of short-circuiting of feed to the tailings. Current columns are typically made very tall, on the order of 30-40 feet, in order to limit the effects […]