Preparation of High Purity Boron by Molten Salt Electroextraction

Molten salt electroextraction (refining) process was conducted to prepare elemental boron using the electrolyte KCl-KBF -KF and boron carbide (B C) as soluble anode. The reactor and the associated equipments for molten salt 4 4 electrolysis were designed and fabricated in-house. The experiments were conducted using the indigenously made electrolytic cell at the temperature of 820°C with a varying time from 3 to 24 h by maintaining constant current. The cathode was removed after cooling and dipped in de-mineralised water for about 4-24 h. The deposited boron was scraped out of the cathode and further milled in planetary ball mill. The milled powder was leached, filtered and subsequently dried in vacuum. The morphology and composition of the electro-deposited boron was characterized using SEM, EDS and chemical analysis. High purity (97.7 ± 1.3%) boron was successfully electro-extracted.