Recovery of rhenium from copper leach solutions using ion exchange with weak base resins

- The adsorption and desorption processes for Re exhibited excellent kinetics properties.
- The optimal process conditions for adsorbing Re by the weak base resin were determined.
- The recovery rate of Re reached 97.13% after 960 BVs of solution flow in industrial experiments.
- The Re concentration enriched 309 times in eluate solution comparing to original leach solution.

This paper investigated the efficient extraction of rhenium from the leach solution generated by roasting the copper concentrates in a copper smelting plant by direct ion exchange process using weak base resins. The adsorption behaviors of rhenium with other coexisting impurity ions belonged to kinetic control by particle diffusion process, and the reaction rate constant was calculated. Then, the influences of temperature, pH value, stirring rate and calcium oxide dosage on the equilibrium adsorption capacity of rhenium were studied by batch experiments. To verify the process of extracting rhenium in industrial application, three ion exchange columns packing with 105 L resins were operated to recover rhenium by direct ion exchange method. In the adsorption process, the recovery rate of rhenium reached 97.13% after approximately 960 BVs of leach solution flow. The loaded resins were eluated using 2.5% concentration of aqueous ammonia, producing a rhenium-rich solution containing 1995 mg/L rhenium, in which the rhenium concentration enriched 309 times compared to the original leach solution.