Processing of enriched elemental boron (10B ∼ 65 at. %)

• Purification of enriched electrodeposited boron.
• Water leaching to remove anionic impurities.
• Acid leaching to remove cationic impurities.
• Optimization of processing parameters.
• Flowsheet for the purification of boron.

Procedures were developed for purification and processing of electrodeposited enriched boron powder for control rod application in India's first commercial Proto Type Fast Breeder Reactor (PFBR). Methodology for removal of anionic (F−, Cl−, −BF4BF4−) and cationic (Fe2+, Fe3+, Ni2+) impurities was developed. Parameters for grinding boron flakes obtained after electrodeposition were optimized to obtain the boron powder having particle size less than 100 μm. The rate of removal of impurities was studied with respect to time and concentration of the reagents used for purification. Process parameters for grinding and removal of impurities were optimized. A flowsheet was proposed which helps in minimizing the purification time and concentration of the reagent used for the effective removal of impurities. The purification methodology developed in this work could produce boron that meets the technical specifications for control rod application in a fast reactor.