Dynamic pore wetting and its effects on porous particle flotation: A review

Abstract

The dynamic pore wetting plays an important role in the flotation of porous particle, such as coal, fly ash, gasification slag, etc. Water phase get into the pores and crevices on the surface and inside of the particles, creating a dense water layer that covers their surface and decreases their floatability. It is important to reduce the adverse impact of dynamic pore wetting on the flotation performance of porous particles. Thus, this review is to highlight the dynamic pore wetting behavior, and its role in the porous particle flotation as well as the proposed regulation methods to weaken the pore wetting. The characterization approaches of the dynamic pore wetting are discussed including the optical method for the capillary and the nuclear magnetic resonance (NMR) method for porous particles. The surface tension and viscosity of liquid significantly affect the pore wetting degree of porous particles during the 60 min wetting process. Pre-wetting time adjustment, pore compression, pore filling, and hydrophobic modifications are introduced to decrease the wetting percentage of pores in porous particles and further improve their flotation performance. This critical review will provide some guidance for studying the dynamic wetting behavior of pores and enhancing the floatability of porous particles.

Keywords

• Pore wetting
• Porous particles
• NMR
• Floatability
• Regulation