mitigation strategy can employ industrial alkaline solid wastes to achieve net emission reduction of atmospheric CO
2
. The red mud is a strong alkalinity waste residue produced from the aluminum industry by the Bayer process which has the potential for the industrial CO
2
large scale treatment. However
limited by complex components of red mud and harsh operating conditions
it is challenging to directly mineralize CO
2
using red mud to recover carbon and sodium resources and to produce mineralized products simultaneously with high economic value efficiently. Herein
we propose a novel electrochemical CO
2
mineralization strategy for red mud treatment driven by hydrogen-cycled membrane electrolysis
realizing mineralization of CO
2
efficiently and recovery of carbon and sodium resources with economic value. The system utilizes H
2
as the redox-active proton carrier to drive the cathode and anode to generate OH
-
and H
+
at low voltage
respectively. The H
+
plays as a neutralizer for the alkalinity of red mud and the OH
-
is used to mineralize CO
2
into generate high-purity NaHCO
3
product. We verify that the system can effectively recover carbon and sodium resources in red mud treatment process
which shows that the average electrolysis efficiency is 95.3% with high-purity (99.4%) NaHCO
3
product obtained. The low electrolysis voltage of 0.453 V is achieved at 10 mA·cm
-2
in this system indicates a potential low energy consumption industrial process. Further
we successfully demonstrate that this process has the ability of direct efficient mineralization of flue gas CO
2
(15% volume) without extra capturing
being a novel potential strategy for carbon neutralization.
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