Study on the inhibition mechanism of guar gum in the flotation separation of brucite and dolomite in the presence of SDS

Abstract

To solve the difficulty in efficient utilization of high-calcium brucite resources, this study focused on the basic research of flotation separation of dolomite from brucite using a selective regulator, namely, guar gum (GG). The flotation tests showed that the floatability of the two minerals was similar in a sodium dodecyl sulfonate (SDS) system. Simultaneously, the use of regulator GG inhibited the floating of dolomite but did not affect the floatability of brucite. The contact-angle measurement visually showed that brucite was relatively higher than dolomite in terms of floatability after the GG action. Zeta-potential measurements demonstrated that GG was more strongly adsorbed on the dolomite surface but less strongly adsorbed on the brucite surface. The infrared-spectrum analysis indicated that GG acted on the surface of the dolomite and hindered the adsorption of SDS on the dolomite surface. However, the opposite was true for brucite. The X-ray photoelectron spectroscopy detection further proved that GG was mainly bound to the Ca sites on the surface of the two minerals, whereas its binding ability to Mg sites was weak.