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FLOTATION (frothers and modifiers). FROTHERS. They role: 1. Gas dispersion 2. Froth formation 3. Speeding up flotation. FROTHERS. FROTHERS. Frothers applied in flotation. FROTHERS. MODIFIERS. 1. Activating reagents 2. Depressants
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FLOTATION (frothers and modifiers)
FROTHERS They role: 1. Gas dispersion 2. Froth formation 3. Speeding up flotation
FROTHERS Frothers applied in flotation
MODIFIERS 1. Activating reagents 2. Depressants They modify: pH, coagulation, redox, rheology, etc.
ACTIVATING REAGENTS Activating action of hydrolyzing cations. Flotation of quartz in the presence of 10–4 M sulfonate. (No flotation in the absence of those cations)
Fluoric ions may activate and depress flotation of silicates: a – area of depressed flotation in presence of oleate b) area of activation in the presence of dodecylamine as collector (Manser, 1975)
Dispersion modifiers Acids, bases, large organic ions iep
Other eg. removing previous reagents from the surface 2C2H5OC(S)SK + 2K2SO3 + 2KHSO3 + 2O2 2C2H5OC(S)SOK 2C2H5OH + 4K2S2O3 + 2CO2