In Situ Reconstruction Regenerates Sinter-Degraded NiO-Based Monolithic Ceramic Catalysts for Efficient Methane Oxidation in Ventilation Air.
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| Title: | In Situ Reconstruction Regenerates Sinter-Degraded NiO-Based Monolithic Ceramic Catalysts for Efficient Methane Oxidation in Ventilation Air. |
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| Authors: | Liu, Fangsheng1 (AUTHOR), Shi, Enming1,2 (AUTHOR), Cao, Zhiqiang1,3 (AUTHOR), Wang, Yeqing1 (AUTHOR), Ou, Xuemei1,2 (AUTHOR), Wang, Zhen1,3 (AUTHOR), Han, Xinyi1 (AUTHOR), Le, Shiru2 (AUTHOR), Wang, Zhijiang2 (AUTHOR), Cheng, Chunlong3 (AUTHOR), Jin, Fangjun1 (AUTHOR) jinfj@cumt.edu.cn |
| Source: | Materials (1996-1944). May2026, Vol. 19 Issue 9, p1677. 11p. |
| Subjects: | Sintering, Catalysts recycling, Thermal stability, Methane flames, Nickel catalysts, Catalysts, Greenhouse gas mitigation |
| Abstract: | Highlights: An in situ reduction–oxidation reconstruction method is proposed to regenerate sinter-degraded NiO-based monolithic ceramic catalysts, effectively reversing NiO agglomeration and coarsening caused by high-temperature sintering. The reconstructed catalyst exhibits remarkably boosted activity and long-term durability for methane oxidation in ventilation air, with robust thermal cycling and reversible steam tolerance. Structural and interfacial regulation synergistically increases active site density and optimizes mass transfer, offering a feasible route to develop sintering-resistant monolithic ceramic catalysts. Monolithic ceramic catalysts are a key technology for the industrial treatment of coal mine ventilation air methane (VAM). The preparation of straight-channel NiO/CeO2 monolithic ceramic catalysts via phase inversion addresses critical bottlenecks for industrial VAM abatement. However, high-temperature sintering leads to irreversible NiO agglomeration and coarsening, severely reducing catalytic activity. In this study, an in situ reduction–oxidation reconstruction method is developed to regenerate sinter-degraded NiO. The reconstructed catalyst increases methane conversion from below 70% after sintering to over 95% at 550 °C and achieves full conversion at 600 °C. The catalyst maintains near 100% conversion during 400 h of continuous operation at 600 °C and shows no performance degradation over 15 thermal cycles. Moreover, the reconstructed catalyst exhibits excellent steam tolerance with fully reversible deactivation. The reconstructed catalyst presents a refined porous structure with BET surface area rising from 4.5 to 11.4 m2 g−1, an elevated Ni3+/Ni2+ ratio (1.47 to 1.97), a higher surface adsorbed oxygen proportion (36.8% to 48.7%) and significantly strengthened NiO-CeO2 interfacial interaction. This work provides a facile and efficient in situ regeneration strategy, greatly enhancing the VAM oxidation activity and stability of sinter-degraded monolithic ceramic catalysts. [ABSTRACT FROM AUTHOR] |
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| Database: | Engineering Source |
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| Abstract: | Highlights: An in situ reduction–oxidation reconstruction method is proposed to regenerate sinter-degraded NiO-based monolithic ceramic catalysts, effectively reversing NiO agglomeration and coarsening caused by high-temperature sintering. The reconstructed catalyst exhibits remarkably boosted activity and long-term durability for methane oxidation in ventilation air, with robust thermal cycling and reversible steam tolerance. Structural and interfacial regulation synergistically increases active site density and optimizes mass transfer, offering a feasible route to develop sintering-resistant monolithic ceramic catalysts. Monolithic ceramic catalysts are a key technology for the industrial treatment of coal mine ventilation air methane (VAM). The preparation of straight-channel NiO/CeO2 monolithic ceramic catalysts via phase inversion addresses critical bottlenecks for industrial VAM abatement. However, high-temperature sintering leads to irreversible NiO agglomeration and coarsening, severely reducing catalytic activity. In this study, an in situ reduction–oxidation reconstruction method is developed to regenerate sinter-degraded NiO. The reconstructed catalyst increases methane conversion from below 70% after sintering to over 95% at 550 °C and achieves full conversion at 600 °C. The catalyst maintains near 100% conversion during 400 h of continuous operation at 600 °C and shows no performance degradation over 15 thermal cycles. Moreover, the reconstructed catalyst exhibits excellent steam tolerance with fully reversible deactivation. The reconstructed catalyst presents a refined porous structure with BET surface area rising from 4.5 to 11.4 m2 g−1, an elevated Ni3+/Ni2+ ratio (1.47 to 1.97), a higher surface adsorbed oxygen proportion (36.8% to 48.7%) and significantly strengthened NiO-CeO2 interfacial interaction. This work provides a facile and efficient in situ regeneration strategy, greatly enhancing the VAM oxidation activity and stability of sinter-degraded monolithic ceramic catalysts. [ABSTRACT FROM AUTHOR] |
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| ISSN: | 19961944 |
| DOI: | 10.3390/ma19091677 |
