2026-10-11T18:20:02Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34040598 2026-10-01T07:06:34Z category_4 category_146 category_7 category_8 category_12 category_24 category_272 category_734 category_132 category_135 portal_63 item_type_6 month_year_10_2026

CO₂ Driven Soot Oxidation via Reverse Boudouard Reaction over Reducible Catalyst: A Sustainable Pathway for Catalyst Regeneration Urmila Mandal (25153740) Sounak Roy (1404115) Biochemistry Space Science Medicine Microbiology Cell Biology Evolutionary Biology Environmental Sciences not elsewhere classified Biological Sciences not elsewhere classified Infectious Diseases Computational Biology term process sustainability saturation overrides differences remarkable inversion occurs related refinery processes oxygen vacancies formed lattice oxygen acts identical light – 800 ° c reverse boudouard reaction oxygen vacancy concentration markedly improves reducibility fluid catalytic cracking reaction xps confirms 4 +</ sup 2 +</ sup 9 </ sub 2 </ sub 1 </ sub aliovalently doped ce reaction xps vacancy replenishment superior reducibility catalytic additives work opens undergo reduction translates directly techniques establishes tangible pathway synthesized via sustainable pathway surface basicity platform chemical marked drop inert n industrial significance dominant product Here, we demonstrate how CO₂ as a mild oxidant can drive soot gasification via the reverse Boudouard reaction, simultaneously regenerating deactivated catalysts and valorizing a greenhouse gas into CO  a platform chemical of industrial significance. Central to this strategy is the ability of CeO₂ to undergo reduction and regeneration: its lattice oxygen oxidizes soot, while the oxygen vacancies formed during this process help activate CO₂ and restore the catalyst. Pristine CeO₂ and aliovalently doped Ce_0.9Ni_0.1O_2−δ were synthesized via a rapid, single-step solution combustion route and benchmarked for CO₂-assisted soot oxidation in a fixed-bed reactor. A suite of techniques establishes that Ni²⁺ incorporation into the CeO₂ fluorite lattice amplifies oxygen vacancy density, enhances lattice oxygen mobility, and markedly improves reducibility. Under inert N₂ atmosphere, where lattice oxygen acts as the sole oxidant, the superior reducibility of Ce_0.9Ni_0.1O_2−δ translates directly into a 75% higher soot conversion compared to pristine CeO₂ at 800 °C, producing CO as the dominant product. Post-reaction XPS confirms a marked drop in Ce⁴⁺ content and a surge in oxygen vacancy concentration, providing unambiguous spectroscopic evidence for lattice oxygen consumption via the Mars–van Krevelen mechanism. When CO₂ is introduced as oxidant, a remarkable inversion occurs: both catalysts now achieve complete soot oxidation with near-identical light–off profiles, as gas-phase CO₂ saturation overrides differences in surface basicity and CO₂ adsorption capacity. Crucially, post-reaction XPS under CO₂ atmosphere reveals a decrease in oxygen vacancy concentration  the fingerprint of vacancy replenishment through CO₂ dissociation and catalyst self-regeneration. This work opens a tangible pathway for deploying CeO₂-based materials as catalytic additives for CO₂-driven regeneration in fluid catalytic cracking and related refinery processes, contributing to both carbon utilization and long-term process sustainability. 2026-10-01T00:00:00Z Text Journal contribution 10.1021/acsomega.6c07523.s001 https://figshare.com/articles/journal_contribution/CO_sub_2_sub_Driven_Soot_Oxidation_via_Reverse_Boudouard_Reaction_over_Reducible_Catalyst_A_Sustainable_Pathway_for_Catalyst_Regeneration/34040598 CC BY-NC 4.0