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Indexed by:Journal Papers

Date of Publication:2020-07-15

Journal:MATERIALS CHEMISTRY AND PHYSICS

Included Journals:SCIE

Volume:249

ISSN No.:0254-0584

Key Words:Electronic waste; Lithium cobalt oxide; Sulfite; Synergy; Water treatment

Abstract:Heterogeneous activation of sulfite by synthetic lithium cobalt oxide (LCO) to treat simulated dye wastewater is developed in this study using Rhodamine B (RhB) as the model pollutant. Synergistic, independent and antagonistic interactions between LCO and Na2SO3 were observed under acid (pH = 3), neutral and alkaline (pH = 10) conditions, respectively. A high mineralization rate of 84% was obtained with 200 mg of LCO and 50 mg of Na2SO3 at pH =3 for 50 mL of 5 mg L-1 RhB substrate. Even hand-shaking with 13 mg of LCO and 3 mg of Na2SO3 for only 30s could realize full de-colorization. Moreover, one-time dosage of 13 mg of LCO and 3 mg of Na2SO3 worked effectively in twenty consecutive batches only if Na2SO3 was periodically supplemented. The radical-trapping experiments determined the SO3 center dot- radical as the dominant reactive species and oxygen vacancies were responsible for sulfite activation. In addition to RhB, the sulfite-enhanced protocol has been universally demonstrated with methyl blue and methyl orange. This paper reflects well the sustainability concept of reusing "wastes" for pollution control since LCO is a key component in the cathode material of abandoned lithium-ion batteries and sulfites are the byproducts of flue gas desulfuration.