A simple combination of zero-valent aluminum and KMnO4 achieved dramatic reduction of high-concentration carbon tetrachloride

Carbon tetrachloride (CT) is a persistent chlorinated organic pollutant frequently detected at high concentrations in industrial wastewater. CT contains four Cl electron-absorbing substituents, which make it difficult to be oxidized but more prone to be reduced. Therefore, we presented a simple and ultrafast approach for the degradation of high-concentration CT by simple physical mixing of ZVAl and KMnO 4 without any addition of organic solvents. This integrated system not only achieved rapid reductive degradation of high-concentration CT under a broad pH range of 3–11 in minutes, but also exhibited strong resistance to interference from dissolved oxygen. During the process, ZVAl and KMnO 4 activated mutually, the mechanism involves following synergistic effects: (1) the oxidation of KMnO 4 promoted the destruction of the passive oxide film on ZVAl, facilitating continuous electron release; (2) these electrons in turn reduce KMnO 4 to generate strongly oxidizing Mn(III) species; (3) the Mn(III) further accelerates ZVAl activation through a self-reinforcing cycle, ultimately facilitating rapid electron-mediated CT reduction. ZVAl/KMnO 4 combined system is expected to realize the quick treatment of CT wastewater, particularly in emergency scenarios involving accidental releases of high-concentration CT.