Investigation on the synergistic mechanism of coal desulfurization by ultrasonic with microwave

Abstract

ABSTRACT This investigation reports the exploration on synergistic action of ultrasound and microwave treatments during coal desulfurization. The sulfur content, surface property, and sulfur form variations of Xinyu coal samples were determined after treating by different methods with peroxyacetic acid, including ultrasonic (US), microwave (MV), MV followed by US (MV-US), and US followed by MV (US-MV). Experimental results showed that in the order of US-MV > MV-US > MV > US had positive effects on coal desulfurization. It was found that the surface characteristics of coal samples were improved due to the physical effects of the US, which was conducive to the further oxidation of sulfur-containing groups in the following MV treatment. The organic sulfur in coal could be oxidized deeply using the combined treatment of US and MV. These findings confirmed that the synergy of US and MV treatments could serve as a reference for further optimizing the coal desulfurization process.