Selective flotation of calcium minerals using double-headed collectors
Journal article, 2019

A study was performed involving a series of double-headed carboxylate collectors with varying distance between the head groups (one, two or three carbon atoms). A collector with the same alkyl chain length but with only one carboxylate group was also included. All these were amino-acid based amphiphiles and the polar head group was connected to the hydrophobic tail via an amide linkage. Selective flotation recovery of different calcium minerals using these collectors was investigated. The double-headed collector with one carbon atom between the carboxylate groups was an apatite and fluorite specific reagent while the monocarboxylate surfactant showed high specificity for calcite. The flotation behavior of a simple conventional collector of the same alkyl chain length, a fatty acid salt, was also determined under identical flotation conditions in order to understand the effect of the amide group. Complementary experiments (ζ potential measurements, adsorption isotherm determinations) were also performed for these reagents. In order to shed light on the selectivity obtained with the dicarboxylate surfactants, the distances between the head groups were calculated and compared with the distances between neighboring calcium atoms on the surface of the minerals. It was found that the high degree of selectivity could be rationalized by perfect matching of these distances. To the best of our knowledge this is the first study where flotation selectivity in complex calcium mineral systems has been explained in terms of molecular recognition governing the interaction between the collector and the mineral surface.

Biodegradable surfactants

calcium minerals

double-headed collector

mineral specific flotation

multilayer adsorption

Author

A. Patra

Luleå University of Technology

Hasan Ali Taner

Luleå University of Technology

Selçuk Üniversitesi

Romain Bordes

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Krister Holmberg

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Anna Carin Larsson

Luleå University of Technology

Journal of Dispersion Science and Technology

0193-2691 (ISSN) 1532-2351 (eISSN)

Vol. 40 8 1205-1216

Subject Categories

Physical Chemistry

Other Chemistry Topics

Organic Chemistry

DOI

10.1080/01932691.2018.1503547

More information

Latest update

11/3/2019