Purification of amorphous boron powder through the removal of impurity magnesium and its physicochemical properties

At present, the most common preparation method of amorphous boron powder is magnesium thermal reduction method, but the amorphous boron powder obtained by this method mostly contains impurities such as magnesium and oxygen which are difficult to remove, and these impurities will seriously affect the application of amorphous boron powder and need to be strictly removed. In this research, the acid-insoluble impurities were modified through sintering and quenching, while the magnesium impurities were optimized via ultrasonic acid leaching. We observed that the quenching temperature played a crucial role in determining the efficiency of magnesium impurity removal. The results show that the magnesium content in amorphous boron powder can be reduced from 5.67% to 2.40% by quenching the amorphous boron powder at 800 °C and using ultrasonic assisted acid leaching. Furthermore, the oxidation reaction of boron is influenced by the powder's particle size and specific surface area, with the effective activation energy being intimately tied to both these factors. Post-quenching and acid leaching, we observed an increase in the specific surface area of the boron powder samples, leading to enhanced activity. In conclusion, our study presents an effective strategy to mitigate magnesium impurities and elevate the performance of amorphous boron powder, offering promising avenues for advancing its utilization across diverse industries.