This invention discloses a stepwise selective electro-oxidation
recovery method and
system for
iodine and
bromine from high-
chlorine brine. This invention utilizes I... ‑ ,Br ‑ Cl ‑ The stepwise difference in the initial oxidation potential is achieved by controlling the anolyte potential relative to the
reference electrode to be in two functional ranges sequentially: the first anolyte potential is higher than that in the brine. ‑ The initial oxidation potential is lower than that of Br. ‑ The initial oxidation potential is higher than that of Br. ‑ The initial oxidation potential is lower than that of Cl. ‑ The initial oxidation potential of I ‑ and Br ‑ After selective oxidation to halogens in steps within the same
electrolysis unit, the halogens are blown out and absorbed separately to obtain
iodine /
bromine enriched solutions. This invention uses electrical energy to replace chemical oxidants such as
chlorine, avoiding the safety risks and
impurity introduction of exogenous oxidants, and reducing I... ‑ and Br ‑ The peroxidation
side reaction is eliminated, and the main
ionic composition of the brine remains basically unchanged after
electrolysis. It can be directly connected to subsequent
lithium,
boron or
potassium extraction processes, realizing the clean and efficient
recovery of trace
halogen resources in
salt lake brine.