Fragmentation behavior of minerals in vanadium slag through electric field intensified ultrasound cavitation.

Ultrasound-assisted leaching is widely applied for extracting valuable metals from mineral resources. The cavitation effects generated by ultrasound treatment (UT) of a solution can fragment minerals that improve the leaching kinetics of the target metals. In this work, the fragmentation behavior of vanadium slag (VS) minerals through electric field intensified ultrasound treatment (EUT) was investigated. It was found that the ultrasonic impact force increased with decreasing ultrasound working distance (WD). Under the action of UT and EUT, the evolution of ultrasonic impact force as a function of ultrasound WD conformed to the natural exponential functional relationship. Inducing electric field into ultrasound field improved ultrasonic impact force, however, the ultrasonic impact force of EUT decayed more rapidly with increasing ultrasound WD. The silicate-wrapped structure of spinel in VS can be destroyed through EUT when the ultrasound WD was smaller than 1 cm. The broken extent of silicates was greater than that of spinel. The EUT had little effect on the fragmentation of the VS particles with particle size (PS) larger than 74 μm. While, it had significant effect on the reduction in PS and the enhancement of specific surface area (SSA) of the VS particles with PS smaller than 74 μm. The PS of the VS with PS smaller than 74 μm decreased by 61.2%, while that of the SSA increased by 18.3 times through EUT, which is beneficial to shortening the leaching time and improving the leaching efficiency of vanadium from the VS.