Understanding the collection behavior of gangue minerals in fine flake graphite flotation

Abstract

Flotation is one of the most common and effective methods for the beneficiation of natural graphite resources. However, the upgrading efficiency of flotation is always finite due to the undesirable collection of gangue minerals. In this work, the collecting mechanism of three typical gangue minerals, including mica, quartz, and feldspar, in fine flake graphite flotation was investigated. Results of batch flotation tests for single-minerals and artificial mixtures confirmed the enhanced collection of gangues in the presence of graphite particles. Contact angle and zeta potential results and theoretical calculations of the interaction between graphite and gangue particles based on typical DLVO theory indicated that it is impossible to collect gangue minerals by true flotation or through heterocoagulation with graphite particles. The fitting results of accumulated gangue recoveries and accumulated water recoveries using the Warren method demonstrated that most gangue minerals entered the concentrate through entrainment, with a small proportion by bubble inclusions.

Innovative correlation relating the destruction of graphite flakes to the morphology characteristics of minerals

“…Natural graphite can be classified as crystalline graphite (flaky and lumpy) and cryptocrystalline graphite based on crystalline morphology (Qui et al, 2022;Xu et al, 2021). The particle size of crystal in flaky graphite is larger than 1 μm, while the large-flake graphite is greater than 0.15 mm (Peng et al, 2016;Shen et al, 2021).…”

Improved Flotation of Fine Flake Graphite Using a Modified Thickening Process

“…In particular, for those fine flake or amorphous graphite resources, up to 10 or more stages of grinding-flotation modules are usually required to allow sufficient dissociation and separation of the graphite and ultrafine scale gangue particles. However, multistage fine grinding drastically deteriorates flotation performance due to the intensified entrainment of fine gangue minerals [16][17][18] and severe slime coating [19]. In addition, an overlong process flowchart yields multiple middling products that require proper treatment [20], placing higher demands on plant operations and imposing a heavy economic burden.…”

Specific Cation Effect on the Flotation of Graphite

“…Froth flotation is one of the most commonly used methods for the beneficiation of natural graphite resources [1][2][3][4]. In graphite flotation, hydrophobic particles are selectively captured and transported by rising air bubbles, leaving hydrophilic gangue minerals in the suspension and discharging as tailings [5].…”