Boron isotope enrichment by countercurrent solvent extraction of boric acid

The BF 3 -based chemical distillation method remains the only industrialized boron isotope separation technique currently in use worldwide. However, this process suffers from some drawbacks, including high corrosiveness, demanding process control, and poor overall economic viability. In contrast, the present study employs a boric acid-based solvent extraction system to achieve boron isotope separation via a multistage countercurrent extraction process. Specifically, a 20-stage setup successfully increased the natural abundance of 11 B from 80.00% to over 81.73%, clearly demonstrating the feasibility of this approach for boron isotope enrichment. Notably, this work represents the first successful experimental demonstration of multistage countercurrent extraction applied to boron isotope separation, offering a promising alternative to conventional industrial methods.