Fuente: WIPO "circular economy" There is disclosed a method and system for utilizing carbon fibres for purification of rejected brine solution comprising thermally recycling carbon fibres and mechanically reducing the recycled carbon fibres, employing a chemical surface activation process for the reduced carbon fibres, resulting in chemically activated recycled carbon fibres; and exposing the activated recycled carbon fibres along with the brine solution to CO2 gas, resulting in the activated recycled carbon fibres selectively recovering contaminants from the brine solution, wherein adsorption of CO2 molecules is also performed by the activated recycled carbon fibres during the recovery. The thermal recycling of carbon fibres is done via pyrolysis and a G-S-L contact system assists in exposing the activated carbon fibres along with the brine solution to CO2 gas at varying flow rates and contact times for recovering contaminants from the brine solution.