Research on the uranium (VI) reduction by free radicals using UV/formic acid process

This study investigated the use of ultraviolet (UV) light irradiation for the activation of formic acid (FA) to reduce U(VI) in aqueous solutions. The results demonstrated that under UV radiation, FA exhibited a higher U(VI) reduction efficiency than other organic acids, and up to 70% of U(VI) in aqueous solutions was successfully removed. Electron spin resonance and methanol quenching experiments confirmed that U(VI) reduction in the UV/FA process was due to the electron transfer facilitated by FA (HCOOH) and CO 2 •− . This catalyst-free UV/FA process holds promise for the reduction of U(VI) in leaking water from uranium tailing ponds.