A promising catalyst for catalytic oxidation of chlorobenzene and slipped ammonia in SCR exhaust gas: Investigating the simultaneous removal mechanism

Chemical Engineering Journal, Год журнала: 2023, Номер 473, С. 145106 - 145106

Опубликована: Авг. 2, 2023

Язык: Английский

---

Engineering a PtCu Alloy to Improve N₂ Selectivity of NH₃–SCO over the Pt/SSZ-13 Catalyst

ACS Applied Materials & Interfaces, Год журнала: 2024, Номер 16(12), С. 14694 - 14703

Опубликована: Март 13, 2024

Improving the N2 selectivity is always a great challenge for selective catalytic oxidation of ammonia (NH3–SCO) over noble-metal-based (especially Pt) catalysts. In this work, Cu as an efficient promoter was introduced into Pt/SSZ-13 catalyst to significantly improve NH3–SCO reaction. A PtCu alloy formed in PtCu/SSZ-13 catalyst, confirmed by X-ray diffraction, transmission electron microscopy, energy dispersive spectrometry mapping, and absorption spectroscopy results. As indicated photoelectron analysis, Pt species alloyed nanoparticle mainly present electron-rich state on PtCu/SSZ-13, while electron-deficient isolated Cu2+ were both surface PtCu/SSZ-13. Due such unique structure with altered state, remarkably improved, activity kept comparable that Pt/SSZ-13. The reaction path changed from NH mechanism internal reduction mechanisms which considered main reason enhanced selectivity. This work provides new route synthesize catalysts optimizing NH3 slip control diesel exhaust purification.

Язык: Английский

---

Reasonable design of Sm-modified Cu-based catalyst for NH3-SCO: Role of the amide intermediates

Applied Catalysis A General, Год журнала: 2023, Номер 666, С. 119409 - 119409

Опубликована: Сен. 1, 2023

Язык: Английский

---

Insight into the performance-boosting mechanism of Ag/MgAlOx for NH3 selective catalytic oxidation: Perspective from the support crystalline phase structures

Journal of Catalysis, Год журнала: 2024, Номер 436, С. 115575 - 115575

Опубликована: Июнь 4, 2024

Язык: Английский

---

NH3-SCO performance-boosting for Ag-based catalysts at low temperature: insight into LDHs-derived MgAl-LDO with low Ag loading

Applied Catalysis B Environment and Energy, Год журнала: 2025, Номер unknown, С. 125031 - 125031

Опубликована: Янв. 1, 2025

Язык: Английский

---

Evolution of specific reaction pathways for the ammonia selective catalytic oxidation reaction over Cu-Ce/SSZ-13 catalysts: Effect of coupling of copper-cerium with zeolite

Separation and Purification Technology, Год журнала: 2024, Номер 349, С. 127727 - 127727

Опубликована: Май 1, 2024

Язык: Английский

---

Asymmetric Coordination of Single-Atom Ru Sites Achieves Efficient N(sp³)–H Dehydrogenation Catalysis for Ammonia Oxidation

Environmental Science & Technology, Год журнала: 2024, Номер 58(24), С. 10717 - 10728

Опубликована: Июнь 7, 2024

Ruthenium single-atom catalysts have great potential in ammonia-selective catalytic oxidation (NH3–SCO); however, the stable sp3 hybrid orbital of NH3 molecules makes N(sp3)–H dissociation a challenge for conventional symmetrical metallic oxide catalysts. Herein, we propose heterogeneous interface reverse atom capture strategy to construct Ru with unique asymmetric Ru1N2O1 coordination. Ru1N2O1/CeO2 exhibits intrinsic low-temperature conversion (T100 at 160 °C) compared symmetric coordinated Ru-based (280 °C), Ir-based (220 and Pt-based (200 catalysts, TOF is 65.4 times that Ag-based The experimental theoretical studies show there strong d–p interaction between N atoms, which not only enhances adsorption ammonia position but also optimizes electronic configuration Ru. Furthermore, affinity water significantly weaker than (the binding energy Pd3Au1 catalyst −1.19 eV, it −0.39 eV our material), so has excellent resistance. Finally, activation requires assistance surface reactive oxygen species, found can directly activate bond without involvement species. This study provides novel principle rational design proximal coordination active sites achieve its optimal activity catalysis.

Язык: Английский

---

Striking Improvement of N₂ Selectivity in NH₃ Oxidation Reaction on Fe₂O₃-Based Catalysts via SiO₂ Doping

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 13, 2025

The emission of NH3 has been reported to pose a serious threat both human health and the environment. To efficiently eliminate NH3, catalysts for selective catalytic oxidation (NH3–SCO) have intensively studied. Fe2O3-based were found exhibit superior activity; however, low N2 selectivity made it less attractive in practical applications. In this work, aimed at improving on catalysts, simple SiO2 doping strategy was proposed. Although activity showed almost no change Fe2O3 after doping, significantly improved. Systematic characterizations revealed that could increase specific surface area Fe2O3, strong interaction Fe–O–Si formed Fe2O3–SiO2 mixed oxide catalysts. Furthermore, abundant Brønsted acid sites due facile hydrolysis structure into Si–OH Fe–OH. weaken redox ability facilitate reaction through an internal SCR (i-SCR) pathway, thus achieving selectivity. This work can provide new insights constructing efficient NH3–SCO with high

Язык: Английский

---

Effect of the Catalyst Support on the NOX Formation During Combustion of NH3 SOFC Off-Gas

Catalysts, Год журнала: 2025, Номер 15(3), С. 196 - 196

Опубликована: Фев. 20, 2025

Ammonia has attracted much interest as a potential green and renewable hydrogen carrier or energy vector. Compared to hydrogen, ammonia offers several advantages. For example, significantly higher density can be liquefied at room temperature moderate pressure of 8 bars. While cracked supply it is also possible convert directly into high-temperature solid oxide fuel cells (SOFCs) generate electricity. The Ship-FC project aims install an ammonia-fed 2MW SOFC system on board the vessel Viking demonstrate feasibility zero CO2 emission shipping. this NH3 system, catalytic afterburner required remove present in off-gas recover heat. current study analysed effects different catalyst supports, with focus NOX formation through combustion surrogate. investigated performance catalysts based active metals, platinum iridium, well Al2O3, SiO2, TiO2. results were correlated characterisation data TPD results. investigations showed that was clearly affected by nature support. highest selectivity towards observed for followed lowest This trend evident supported iridium samples exclusively containing N2O opposite (TiO2 > SiO2 Al2O3) both presence absence iridium.

Язык: Английский

---

Advances and Challenges in Zeolite-Based Catalysts for the Selective Catalytic Oxidation of Ammonia

Catalysts, Год журнала: 2025, Номер 15(3), С. 204 - 204

Опубликована: Фев. 21, 2025

Ammonia (NH3) emissions from mobile sources pose significant environmental challenges, contributing to air pollution, ecosystem degradation, and climate change. The selective catalytic oxidation of NH3 (NH3-SCO) offers a sustainable solution by converting into nitrogen water, yet designing catalysts that balance high efficiency, selectivity, stability under operational conditions remains critical challenge. This review provides comprehensive overview zeolite-based catalysts, renowned for their surface area, tunable pore structures, exceptional hydrothermal stability, which make them ideal NH3-SCO applications. synthesizes recent advancements in catalyst design, emphasizing innovative architecture, the role zeolite frameworks active site dispersion, strategies optimizing architectures. Key insights include an enhanced understanding reaction mechanisms, progress mitigating deactivation caused poisoning sintering, development bimetallic core-shell improve performance durability. Current limitations, including sensitivity environments scalability issues, are critically analyzed, potential overcoming these barriers proposed. highlights state-of-the-art catalysis, offering valuable fundamental applied aspects design. findings presented here provide roadmap future innovations paving way more efficient robust solutions ammonia emission control.

Язык: Английский

---