Inhibition Mechanism of a Novel Inhibitor on Apatite and its Response to the Separation of Apatite and Dolomite: Experimental and Md Simulation Studies

Abstract

The effective flotation of middle and low-grade collophane poses a global challenge. The utilization of novel inhibitors in the reverse flotation for phosphate ore is gaining significance. This study uses the mixed TA (tartaric acid) and ASO (aluminum sulfate octadecahydrate) to effectively inhibit apatite flotation. Micro-flotation experiments were performed to investigate the separation performance of dolomite from apatite using the mixed inhibitor TA/ASO. A range of analytical techniques, including ICP-OES, solution chemistry calculations, zeta potentials, FTIR, XPS, and molecular dynamics (MD) simulation, were conducted to unveil the selective inhibition mechanism of the mixed inhibitor on the two minerals. In sodium oleate (NaOL) collector system, the application of TA/ASO successfully separated dolomite from apatite, and yielding a concentrate with 28.58% P2O5 grade and 97.78% P2O5 recovery in artificially mixed mineral tests. The mechanism studies demonstrate that ASO and TA experience simultaneous adsorption on the apatite surface, leading to a collaborative suppression of apatite flotation. The preferential adsorption of TA/ASO on the apatite surface instead of dolomite intensified the disparity in surface wettability between the two minerals, resulting in distinct adsorption disparity of collector and successfully achieving the selective flotation of dolomite from apatite. These findings indicate a promising potential for the utilization of TA/ASO in the environmentally friendly and effective processing of phosphate ore.

Keywords: Dolomite, Fluorapatite, Reverse flotation, Mixed inhibitor, Efficient separation