Improved performance of Mn-, Co-based oxides from spent lithium-ion batteries supported on CeO2 with different morphologies for 2-ethoxyethyl acetate oxidation

Abstract

Faced with a large amount of spent lithium-ions batteries from new energy vehicles and portable electronic devices such as personal computers and mobile phones. If they are not treated properly, they would not only result in serious environmental pollution but also lead to the loss of valuable resources like Co and Li. At present, most of researchers mainly focused on the metal recovery via hydrometallurgical and pyrometallurgical method. In this work, manganese-based metal oxides (MnOx(SY), MnOx(MS)) and cobalt-based oxides (CoOx(GS)) are synthesized using manganese and cobalt-based metals recovered from spent ternary, manganate and cobaltate lithium-ion batteries as a precursor, respectively. A series of supported multi-metal oxides were prepared by supporting 10% (wt) of MnOx(SY), MnOx(MS) and CoOx(GS) on CeO2 with different morphologies via impregnation method. The catalytic activities of the metal oxides during the oxidation of 2-ethoxyethyl acetate are investigated. The results obtained show that MnOx(MS)/CeO2-C, MnOx(SY)/CeO2-C and CoOx(GS)/CeO2-P have better catalytic performances due to their excellent physicochemical properties compared to the MnOx(SY), MnOx(MS), CoOx(GS), CeO2-R, CeO2-P, CeO2-C, MnOx(MS)/CeO2-R, MnOx(MS)/CeO2-P, MnOx(SY)/CeO2-R, MnOx(SY)/CeO2-P, CoOx(GS)/CeO2-R, CoOx(GS)/CeO2-C. In-situ diffuse reflectance infrared fourier transform spectroscopy results prove that gaseous O2 plays a vital role in facilitating the complete oxidation of intermediates such as ‒C˭O, ‒COO, ‒C‒O‒C, ‒C‒O into CO2 during 2-ethoxyethyl acetate oxidation. Furthermore, thermal desorption/gas chromatography-mass spectrometer results show that the main by-products obtained during 2-ethoxyethyl acetate oxidation are ethanol,2-methoxy-; ethanol, 2-methoxy-, acetate and acetic acid.