Exploration of the interaction mechanism in the synergistic degradation of benzene and toluene over MnCoO_x catalysts

Highlights

	● A series of MnaCobO x (a:b = 1:2, 1:1, and 2:1) catalysts are prepared.
	● Effects of Mn/Co for catalytic performance are studied.
	● T90 of benzene and toluene in the mixture over MnCoO x are 290 and 248 °C.
	● The reaction mechanism of benzene and toluene synergistic oxidation is proposed.

Abstract

The catalytic degradation of single-component VOCs has been widely studied. However, several types of VOCs may be present in an actual industrial emission stream. Efficient synergistic removal of multicomponent VOCs is currently a popular research topic. Herein, Mn–Co samples with various Mn/Co ratios (1:2, 1:1, and 2:1) were successfully prepared, and the catalytic oxidation performance characteristics toward benzene and toluene over these samples under single and binary VOC oxidation conditions were studied. Compared with pure MnO_x and CoO_x, the prepared Co–Mn composite oxide samples exhibited significantly improved catalytic performance. MnCoO_x and MnCo₂O_x showed optimum catalytic performance, with 100% benzene and 100% toluene conversion in the mixtures at 300 and 350 °C, 100% CO₂ selectivity. Characterization methods were employed to elucidate the relevance of the catalytic activity to the structures, acidity, redox properties, Mn–Co valence state and oxygen species. Moreover, the interactions between benzene and toluene during their synergistic degradation, as well as the intermediates and potential reaction mechanisms of their simultaneous elimination, were investigated. Utilizing Mn–Co oxide compounds for cooperative catalytic oxidation of benzene and toluene represents a viable and effective technique for the practical and synergist elimination of multicomponent VOCs.

Graphical abstract

Keywords

Mn–Co oxides / Synergetic catalytic oxidation / Benzene and toluene / Reaction mechanism

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 22206146, 22006079, and U21A20524), the Fundamental Research Funds for the Central Universities (China), the Youth Innovation Promotion Association of Chinese Academy of Sciences, the Fundamental Research Program of Shanxi Province (China) (No. 202103021223280).

Conflict Interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Electronic Supplementary Material

Supplementary material is available in the online version of this article at https://doi.org/10.1007/s11783-025-1942-6 and is accessible for authorized users.

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