Research on the Preparation of Kaolin from Coal Gangue by Flotation Decarburization with Different Collectors

Abstract

In order to find a better collector for the separation of carbon and kaolin from coal gangue flotation, and to explore the action mechanism of collectors, this paper selected 12 kinds of collectors for systematic comparison, including five non-polar organics with different carbon chain lengths, and polar organic matters with double bonds, triple bonds, benzene, as well as cycloalkyl, ester, carboxyl, and aldehyde groups. The flotation results show that the longer carbon chain (with a carbon atom number of 13~15), the better the flotation effect, the better the effect of the collector with the phenyl group (among the four hydrocarbon groups), and the better the effect of the collector with the ester group (among the three functional groups). In order to explore the flotation mechanism at the microscopic level, the molecular structure of carbon in coal gangue was detected using a solid nuclear magnetic test. Afterwards, the organic macromolecule model of carbon was simulated. Finally, the interaction energy values between carbon and collectors were calculated in accordance with the density functional theory, and the order of the acting force of collectors was obtained, which was consistent with that of the collectors in the macro experiment.