Leaching kinetics of magnesium extraction from boron mud in ammonium bisulphate solutions

Abstract

In this study, the leaching kinetics of magnesium of boron mud (BM) is evaluated using NH4HSO4 solution. The effects of leaching temperature, leaching time, ammonium bisulphate solution concentration and liquid–solid ratio on the extraction ratio of magnesium are investigated. Optimum leaching parameters are determined through an orthogonal test based on single factor experiments. Under the optimum leaching temperature (333 K), leaching time (40 min), NH4HSO4 concentration (2.8 mol · L−1), and liquid–solid ratio (9:1 mL · g−1), the extraction ratio of magnesium was 76.73%. In addition, the leaching kinetics data of magnesium from BM are analyzed through graphical and statistical approaches, which reveal that the leaching process conforms to the grain model. The leaching process is diffusion‐controlled with an activation energy of 41.67 kJ · mol−1.