Efficient Separation of Ultrafine Coal Assisted by Selective Adsorption of Polyvinylpyrrolidone

Abstract

The efficient separation of ultrafine coal is a challenging process due to the ultrafine particle size and gangue entrainment. In this study, a polymer, polyvinylpyrrolidone (PVP), was introduced as a regulator for ultrafine coal beneficiation. The addition of PVP improved the combustible recovery of clean coal and decreased the ash content. This effect was also presented by the selectivity index. The regulation mechanism of PVP was investigated using diverse methods. The adsorption tests performed demonstrated the adsorption amount of PVP on coal, kaolinite, and quartz, which were related to the increase in the separation efficiency. A zeta potential analyzer was employed to elucidate the effect of PVP on the electrical properties of ultrafine particles. The results revealed that the electrokinetic potential of mineral was sensitive to the varying PVP concentration. The particle size distribution was observed to value the influence of PVP on the particle behavior, which was tested by a laser particle size analyzer. X-ray photoelectron spectroscopy was used to investigate the surface elemental compositions of coal, kaolinite, and quartz, which were regulated by the adsorption of PVP. This research is beneficial to understanding the role of PVP as regulators and provides a basis for the efficient separation of ultrafine coal.