EX-SOLVED NI-CO BIMETALLIC NANOCATALYSTS FROM PEROVSKITE PRECURSORS FOR STEAM METHANE REFORMING: MECHANISMS OF HIGH RESISTANCE TO COKING AND SINTERING

Sherzod Omonov; Shuhratqodir G'ulomov; Iskandar O'rinbadalov

doi:10.66960/jof.3093-8899.00025

Authors

Sherzod Omonov Author https://orcid.org/0009-0009-4326-2207
Shuhratqodir G'ulomov t.f.f.d., dots Author https://orcid.org/0000-0002-5793-3018
Iskandar O'rinbadalov Author

DOI:

https://doi.org/10.66960/jof.3093-8899.00025

Keywords:

In situ ex-solution, Ni-Co bimetallic catalyst, Defective perovskite oxide, Coking resistance, Hydrogen production

Abstract

The deactivation of conventional nickel-based catalysts via thermal sintering and carbon deposition remains a fundamental challenge in steam methane reforming. To address this, we report the rational design of a highly active and exceptionally robust ex-solved bimetallic catalyst supported on a defective perovskite oxide, . Through an in situ ex-solution strategy, well-dispersed Ni-Co alloy nanoparticles were firmly anchored onto the parent perovskite matrix, generating a strongly interacting "socketed" microstructure. The catalyst exhibited superior Steam methane reforming performance, achieving a maximum CH₄ conversion of 92.5% at 850 °C under atmospheric pressure. Notably, the catalyst demonstrated outstanding long-term structural and operational stability, sustaining a constant CH₄ conversion rate with negligible degradation during a continuous 100-h time-on-stream test at 800 °C. Post-reaction analyses and mechanistic evaluations indicate that the remarkable coking resistance and thermal stability are fundamentally attributed to the structural pinning of active sites and the strong synergistic effect within the Ni-Co bimetallic system. "The developed NiCo@STNC system exhibits significantly enhanced stability and resistance to carbon deposition, addressing the rapid deactivation commonly observed in conventional supported Ni catalysts". The novelty of this work lies in elucidating the anti-coking mechanism of Ni–Co exsolved nanoparticles under steam-rich SMR conditions. Furthermore, the enhanced lattice oxygen mobility provided by the defective perovskite support collaboratively promotes the rapid gasification of carbonaceous intermediates. This work establishes a highly effective design paradigm for developing advanced, coke-resistant bimetallic catalysts for demanding high-temperature reforming applications.

Author Biographies

Sherzod Omonov

Toshkent kimyo texnologiya instituti. Neft va gazni qayta ishlash kimyoviy texnologiyasi kaferasi assistenti
Shuhratqodir G'ulomov, t.f.f.d., dots

Toshkent kimyo texnologiya instituti. Neft va gazni qayta ishlash kimyoviy texnologiyasi kaferasi dotsenti
Iskandar O'rinbadalov

Toshkent kimyo texnologiya instituti. Neft va gazni qayta ishlash kimyoviy texnologiyasi kaferasi talabasi

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