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Generation and Control of Electrohydrodynamic Flows in Aqueous Electrolyte Solutions
Published on: September 7, 2018
Electrokinetic properties of wavellite and its floatability with cationic and anionic collectors
Aline Pereira Leite Nunes1, Antônio Eduardo Clark Peres, Armando Corrêa de Araujo
1Department of Mining Engineering, Federal University of Minas Gerais, Engineering School, Avenida Antônio Carlos, 6627-Bloco II/4236 CEP: 31270-901, Belo Horizonte, MG, Brazil. aline@demin.ufmg.br
Journal of Colloid and Interface Science
|July 2, 2011
Summary
Cationic reverse flotation effectively removes phosphorus from iron ores by targeting secondary minerals like wavellite. This method shows promise for improving ore quality, even with common depressants present.
Area of Science:
- Mineral Processing
- Extractive Metallurgy
- Surface Chemistry
Background:
- Traditional anionic reverse flotation faces challenges with secondary phosphorus minerals like wavellite in iron ores.
- Efficient phosphorus reduction is crucial for upgrading magmatic origin iron ores.
Purpose of the Study:
- Investigate the floatability of wavellite using cationic and anionic collectors.
- Determine the optimal conditions for wavellite flotation to reduce phosphorus content in iron ores.
Main Methods:
- Zeta potential measurements to understand wavellite surface charge.
- Microflotation tests with various collectors (anionic and cationic).
- Analysis of surface interactions and adsorption mechanisms.
Main Results:
- Wavellite exhibits an isoelectric point (IEP) at pH 4.5.
- Cationic collectors significantly enhance wavellite floatability under alkaline conditions.
- Surface complex formation and aluminum oleate precipitation are key adsorption mechanisms.
Conclusions:
- Cationic reverse flotation is a viable strategy for removing secondary phosphates (wavellite) from iron ores.
- This method is effective even in the presence of corn starch, a common depressant.
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