A modelling approach to kinetics study and novel monolith channel design for selective catalytic reduction (SCR) applications

Shin, Sang Baek; Skau, Karl Isak; Menon, Mohan; Maroor, Sreekumar; Spatenka, Stepan

doi:10.1016/j.cherd.2018.12.029

Cited by 14 publications

(8 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is suggested that honeycomb monoliths with a wall thickness of 0.5–0.6 mm and a channel width of 3–4 mm are suitable for the case of low dust gas, while greater wall thickness (>1 mm) and larger channels (e.g., 7 mm) are applicable for the flue gas with high dust content . Shin et al . found that elongated hexagonal channels have higher NO conversion than the conventional square channels.…”

Section: Monolith Catalystsmentioning

confidence: 99%

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

et al. 2019

View full text Add to dashboard Cite

Selective catalytic reduction with NH 3 (NH 3 −SCR) is the most efficient technology to reduce the emission of nitrogen oxides (NO x ) from coal-fired industries, diesel engines, etc. Although V 2 O 5 −WO 3 (MoO 3 )/TiO 2 and CHA structured zeolite catalysts have been utilized in commercial applications, the increasing requirements for broad working temperature window, strong SO 2 /alkali/heavy metal-resistance, and high hydrothermal stability have stimulated the development of new-type NH 3 −SCR catalysts. This review summarizes the latest SCR reaction mechanisms and emerging poisonresistant mechanisms in the beginning and subsequently gives a comprehensive overview of newly developed SCR catalysts, including metal oxide catalysts ranging from VO x , MnO x , CeO 2 , and Fe 2 O 3 to CuO based catalysts; acidic compound catalysts containing vanadate, phosphate and sulfate catalysts; ion exchanged zeolite catalysts such as Fe, Cu, Mn, etc. exchanged zeolite catalysts; monolith catalysts including extruded, washcoated, and metal-mesh/foam-based monolith catalysts. The challenges and opportunities for each type of catalysts are proposed while the effective strategies are summarized for enhancing the acidity/redox circle and poison-resistance through modification, creating novel nanostructures, exposing specific crystalline planes, constructing protective/sacrificial sites, etc. Some suggestions are given about future research directions that efforts should be made in. Hopefully, this review can bridge the gap between newly developed catalysts and practical requirements to realize their commercial applications in the near future.

show abstract

Section: Monolith Catalystsmentioning

confidence: 99%

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Activities and selectivities were measured on 1 cm mini monoliths as described before [17] by mass spectrometry using helium as a background gas. The piece five from the inlet was used in the ammonia oxidation experiments.…”

Section: Measurements Of Catalyst Activity and Selectivitymentioning

confidence: 99%

“…The model was able to predict the catalyst output during the European Transient Cycle (ECT cycle). A recent paper [17] presented a method to simulate the kinetics of the SCR reactions as well as many of the NH 3 oxidation ones to obtain novel and better monolith channel designs. The results are detailed showing, among others, the temperature profile in the catalyst bed when converting 1500 ppm NO with NH 3 in the SCR process.…”

Section: Introductionmentioning

confidence: 99%

Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V2O5/TiO2 Monolithic Diesel SCR Catalyst Using a Multichannel Model

Odenbrand¹

2020

AJCHE

View full text Add to dashboard Cite

The background to this study is the need to find out if some reactions of O 2 oxidation of ammonia oxidation are important in the Selective Catalytic Reduction (SCR) of NO by NH 3 . The objective of the study was to shed light on the influence of poisoning on these reactions over a diesel SCR catalyst by compounds in the exhaust gases. The method used was to experimentally determine the amounts of products formed at several temperatures and compared them to simulated values. About 700 ppm NH 3 was oxidized by 2% O 2 in helium yielding N 2 , N 2 O, and NO at increasing temperatures. Comparisons are given for a 4.56% vanadia on titania fresh catalyst and the ones used for 890 and 2299 h. The kinetics was simulated using a multichannel model of the monolithic catalyst. The experimental values of the products were nicely fitted by the kinetic model where all three ammonia oxidation reaction rates were of the first order in the concentration of ammonia. The fit was somewhat better for the non-isothermal case than the isothermal one. The deactivation reduces the activation energies for the formation of all products. Effects of flow and concentration maldistribution are shown to be present but are quite small. The temperature increase is 1.30 K for the most active catalyst at the highest temperature (733 K). The use of the multichannel model shows that quite considerable deviations in inlet ammonia concentrations are obtained over the catalyst cross section. This means that the catalyst is not used to its full potential.

show abstract

“…Mathematical modelling plays an important role in developing a new catalytic technology or for improving the design of existing reactors. The performance of a monolithic reactor is a complex function of design parameters, operating conditions, and properties of both the catalyst and reaction mixture [27,[30][31][32][33]. The approach to design and analyse catalytic SCR reactor customarily adopted in the early literature was based on pseudo-homogeneous models accounting for axial concentration gradients [4,28,29,34].…”

Section: Introductionmentioning

confidence: 99%

“…Depending on the objectives, applications and computational limitations, these models can be classified as one-dimensional (1-D), two-dimensional (2-D) and three-dimensional models (3-D), or as washcoat (catalyst layer), single channel, or multichannel (full reactor). [22,27,28,[31][32][33][34][35].…”

Section: Introductionmentioning

confidence: 99%

A Modelling Approach of the Catalytic Oxidation of Volatile Organic Compounds in the SCR-DeNOx Monolithic Reactor

Lazar¹,

Koeser²,

Fechete³

et al. 2020

Rev. Chim.

View full text Add to dashboard Cite

Monolithic reactors play an important role in the integrated approach to environmental protection, especially in air pollution abatement. Mathematical modelling of catalytic reactors has become a key procedure in the design, development and optimisation of many industrial processes. The objective of this study was the modelling and simulation of the catalytic oxidation of volatile organic compounds by a commercial V2O5-WO3/TiO2 honeycomb catalyst, specific for the SCR-DeNOx process in high-dust flue gases from stationary incineration. The mathematical model is developed for the numerical simulation of a tubular plug flow reactor, using mass balance equation to predict results for benzene conversion under isothermal conditions.

show abstract

A modelling approach to kinetics study and novel monolith channel design for selective catalytic reduction (SCR) applications

Cited by 14 publications

References 46 publications

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V<sub>2</sub>O<sub>5</sub>/TiO<sub>2</sub> Monolithic Diesel SCR Catalyst Using a Multichannel Model

A Modelling Approach of the Catalytic Oxidation of Volatile Organic Compounds in the SCR-DeNOx Monolithic Reactor

Contact Info

Product

Resources

About

A modelling approach to kinetics study and novel monolith channel design for selective catalytic reduction (SCR) applications

Cited by 14 publications

References 46 publications

Selective Catalytic Reduction of NOx with NH3 by Using Novel Catalysts: State of the Art and Future Prospects

Selective Catalytic Reduction of NOx with NH3 by Using Novel Catalysts: State of the Art and Future Prospects

Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt;/TiO&lt;sub&gt;2&lt;/sub&gt; Monolithic Diesel SCR Catalyst Using a Multichannel Model

A Modelling Approach of the Catalytic Oxidation of Volatile Organic Compounds in the SCR-DeNOx Monolithic Reactor

Contact Info

Product

Resources

About

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

Selective Catalytic Reduction of NO_x with NH₃ by Using Novel Catalysts: State of the Art and Future Prospects

Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V<sub>2</sub>O<sub>5</sub>/TiO<sub>2</sub> Monolithic Diesel SCR Catalyst Using a Multichannel Model