Flotation selectivity of novel alkyl dicarboxylate reagents for apatite-calcite separation
Journal article, 2015

The investigation aims to demonstrate the conceptual thoughts behind developing mineral specific reagents for use in flotation of calcium containing ores. For this purpose, a series of dicarboxylate-based surfactants with varying distance between the carboxylate groups (one, two or three methylene groups) was synthesized. A surfactant with the same alkyl chain length but with only one carboxylate group was also synthesized and evaluated. The adsorption behavior of these new reagents on pure apatite and pure calcite surfaces was studied using Hallimond tube flotation, FTIR and zeta potential measurements. The relation between the adsorption behavior of a given surfactant at a specific mineral surface and its molecular structure over a range of concentrations and pH values, as well as the region of maximum recovery, was established. It was found that one of the reagents, with a specific distance between the carboxylate groups, was much more selective for a particular mineral surface than the other homologues. For example, out of the four compounds synthesized, only the one where the carboxylate groups were separated by a single methylene group floated apatite but not calcite, whereas calcite was efficiently floated with the monocarboxylic reagent, but not with the other reagents synthesized. This selective adsorption of a given surfactant to a particular mineral surface relative to other mineral surfaces as evidenced in the flotation studies was substantiated by zeta potential and infra-red spectroscopy data.

Monolayers

Acids

Froth flotation

Surfaces

Adsorption

Mineral processing

Surfactant

Crystallization

Mineral specific reagents

Surfactants

Author

T. Karlkvist

Luleå University of Technology

A. Patra

Luleå University of Technology

K. H. Rao

Luleå University of Technology

Romain Bordes

SuMo Biomaterials

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Krister Holmberg

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Journal of Colloid and Interface Science

0021-9797 (ISSN) 1095-7103 (eISSN)

Vol. 445 40-47

Subject Categories

Physical Chemistry

DOI

10.1016/j.jcis.2014.11.072

More information

Latest update

8/18/2020