A progressive review on NO purification from diesel vehicle exhaust: From technology development to material active sites analysis

Separation and Purification Technology, Год журнала: 2024, Номер 354, С. 129111 - 129111

Опубликована: Авг. 6, 2024

Язык: Английский

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Toward synergetic reduction of pollutant and greenhouse gas emissions from vehicles: a catalysis perspective

Chemical Society Reviews, Год журнала: 2024, Номер unknown

Опубликована: Дек. 17, 2024

It is a great challenge for vehicles to satisfy the increasingly stringent emission regulations pollutants and greenhouse gases. Throughout history of development vehicle control technology, catalysts have always been in core position aftertreatment. Aiming address significant demand synergistic gases from vehicles, this review provides panoramic view technologies key aftertreatment using fossil fuels (gasoline, diesel, natural gas) carbon-neutral (hydrogen, ammonia, green alcohols). Special attention will be given research advancements catalysts, including three-way (TWCs), NO

Язык: Английский

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One zeolite for multiple Fe species

Nature Catalysis, Год журнала: 2024, Номер 7(12), С. 1255 - 1256

Опубликована: Дек. 20, 2024

Язык: Английский

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High-Performance Strategy and Degradation Mechanism of Cezrvox Catalysts for Nox Reduction

Опубликована: Янв. 1, 2024

The denitrification (deNOx) performance of catalysts is affected directly by redox ability and surface acidity,and regulating the balance between both which a major step toward enhancing catalysts.The CeZrOx catalyst has garnered widespread attention in field deNOx due to its excellent oxygen storage capacity. This study uses VOx as an acid promoter adjust centers acidity sites on catalyst, utilizing synergistic effect demonstrate optimal performance. experimental results indicate that doping appropriate amount can effectively enhance NH3-SCR activity Ce0.60Zr0.40Ox, while also improving resistance SO2 H2O. Characterization confirm that, active species Ce0.50Zr0.40V0.10Ox increase V enhances catalyst's properties comparing with obtains more Brønsted Lewis sites, adjusting thus playing promoting role. possesses lowest apparent activation energy (Ea), adsorption capability for NH3 increasing reaction rate adsorbed gaseous NO + O2, thereby exhibiting ZrOx would provide gas molecules, ZrVOx-CeO2 surface. provides valuable insight preparation new efficient using strategy synergistically reduction sites.

Язык: Английский

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Exploring the limit of Cu-based small-pore zeolite framework collapse during hydrothermal aging in NO abatement from diesel vehicle exhaust

Journal of Environmental Sciences, Год журнала: 2024, Номер unknown

Опубликована: Июль 1, 2024

Язык: Английский

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Interface Induced by Hydrothermal Aging Boosts the Low-Temperature Activity of Cu-SSZ-13 for Selective Catalytic Reduction of NO_x

Environmental Science & Technology, Год журнала: 2024, Номер unknown

Опубликована: Авг. 13, 2024

Hitherto, sulfur poisoning and hydrothermal aging have still been the challenges faced in practical applications of Cu-SSZ-13 catalyst for selective catalytic reduction (SCR) NOx from diesel engine exhaust. Here, we elaborately design conduct an in-depth investigation synthetic effects SO2 on pristine [email protected] core@shell structure catalysts (Cu@CZ). It has discovered that Cu@CZ susceptible to 750 °C with 5 vol % H2O followed by 200 ppm (Cu@CZ-A-S) could maintain nearly 100% conversion across significantly wider temperature region 200–425 °C, which is remarkably broader than Cu-SSZ-13-A-S (300–400 °C) counterpart. The experimental results show process migration highly active Cu species within cage CZ surface, forming CuO/CZ abundant interfaces, enhances adsorption subsequent activation NO, leading generation reactive N2O3 HONO intermediates. Moreover, density functional theory (DFT) calculations reveal H HONO* can function as Brønsted acid sites, effectively adsorbing NH3 generate NH4NO2* intermediate, readily decomposes into N2 H2O. Furthermore, this pathway rate-determining step energy barrier 0.93 eV, notably lower "standard SCR" (1.42 eV). Therefore, formation new interface profoundly boosts low-temperature NH3-SCR activity improves coresistance aging.

Язык: Английский

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High-Performance strategy and degradation mechanism of CeZrVOx catalysts for NOx reduction

Separation and Purification Technology, Год журнала: 2024, Номер 353, С. 128288 - 128288

Опубликована: Июнь 5, 2024

Язык: Английский

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Synthesis of Chabazite Zeolite via Faujasite Conversion Using 1‐(1‐Methylpropyl)‐4‐aza‐1‐azoniabicyclo[2.2.2]octane Hydroxide as Cost‐Effective Structure‐Directing Agent

ChemCatChem, Год журнала: 2024, Номер 16(21)

Опубликована: Июль 15, 2024

Abstract Cu‐exchanged chabazite zeolite is the state‐of‐the‐art used on‐board catalyst for NO x selective reduction by ammonium (NH 3 ‐SCR), and currently generated in presence of N , ‐trimethyl‐1‐adamantylammonium hydroxide, serving as organic structure‐directing agent (OSDA). The expensiveness this OSDA increases production cost, while its low degradability brings about environmental concerns post treatment waste water. Here, a new type OSDA, 1‐(1‐methylpropyl)‐4‐aza‐1‐azoniabicyclo[2.2.2]octane proposed to direct Faujasite‐to‐Chabazite inter‐zeolite conversion generate with Si/Al ratio up 7.2. obtained possesses high hydrothermal stability crystallinity, siliceous framework concentrations Si(2Si, 2Al) sites. Cu‐form exhibits better catalytic performance standard NH ‐SCR process tiny crystallite size (35–258 nm) formation highly dispersed copper synthesis offers fabricate zeolites expands toolkit regulate their physicochemical properties.

Язык: Английский

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Unlocking the potential for pseudo-molecular catalysts via understanding the activity of transition metal ionic species in zeolites

Chem Catalysis, Год журнала: 2024, Номер unknown, С. 101130 - 101130

Опубликована: Окт. 1, 2024

The bigger pictureTransition metal ions (TMIs) hosted in zeolites have been revealed as a class of heterogeneous catalysts with remarkable activity and robustness for diverse applications. catalytic mechanisms at play are not yet described molecular level, due to the lack understanding speciation TMI subsequent formation active sites zeolites.The TMIs is complex depends on multiple parameters, ranging from zeolite properties loadings mobility under reaction conditions, their local environment framework. Synthetic methods often overlook many these factors, this fact leads highly materials.Advances spectroscopic analytic shed light structure dynamics zeolites. Future research should focus operando characterization materials where complexity reduced minimum, aided by theoretical calculations.SummaryTransition potential generating selective catalysts. inside microporous pore system, including geometric constraints anchoring points, grouping, nuclearity species, well understood. Determination location challenging because different species co-exist same zeolite, added conditions. Three parameters influential zeolites: (1) properties, framework structure, composition, loadings; (2) micropores; (3) influence other inorganic present spaces. In our view, molecular-level metal-ion-exchanged requires set computational techniques that go hand refined synthetic selectively species.Graphical abstract

Язык: Английский

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Deterioration Analysis of Real-world SCR Catalysts in Diesel Vehicles

International Journal of Automotive Manufacturing and Materials, Год журнала: 2024, Номер unknown, С. 5 - 5

Опубликована: Ноя. 28, 2024

Article Deterioration Analysis of Real-world SCR Catalysts in Diesel Vehicles Tongliang Zhang 1,2,3, Yu Sun 3, Xusheng Xiang 4, Wenqing Ding 2,3, Zhen Chen Caiyue Dong Yating Li Yulong Shan 3,*, Yunbo 2,3 and Hong He 1,2,3 1 School Rare Earths, University Science Technology China, Hefei 230026, China 2 Ganjiang Innovation Academy, Chinese Academy Sciences, Ganzhou 341119, 3 State Key Joint Laboratory Environment Simulation Pollution Control, Research Center for Eco-Environmental Beijing 100085, 4 Dongfeng Commercial Vehicle Co., Ltd., Shiyan 100049, * Correspondence: [email protected] Received: 12 August 2024; Revised: 22 October Accepted: 24 Published: 28 November 2024 Abstract: To investigate the real-world poisoning Cu-SSZ-13 NH3-SCR (Selective Catalytic Reduction with NH3) catalysts diesel vehicles, three used from vehicles that have traveled different distances were analyzed. The deterioration observed these significantly differs laboratory simulations due to combined effect multiple factors. degree catalyst is positively correlated not only driving distance but also specific types encountered. In conditions, hydrothermal aging primary factor. Instead, main cause deactivation by chemical elements such as sulfur iron. Sulfur reduces catalytic activity, regeneration depends on species formed. This study reveals accumulation poisons reason conditions. Therefore, reducing toxic components engine exhaust essential maintaining performance.

Язык: Английский

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