Patent
Process and catalyst for reducing nitrogen oxides
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TLDR
In this article, a selective catalytic reduction on a reduction catalyst using ammonia is described, where a fraction of the nitrogen monoxide present in the exhaust gas is oxidized to nitrogen dioxide before the exhaust gases, together with ammonia, are passed over the reduction catalyst.Abstract:
A process for reducing the nitrogen oxides present in a lean exhaust gas from an internal combustion engine by selective catalytic reduction on a reduction catalyst using ammonia, wherein a fraction of the nitrogen monoxide present in the exhaust gas is oxidized to nitrogen dioxide before the exhaust gas, together with ammonia, is passed over the reduction catalyst. The reduction catalyst contains a zeolite exchanged with transition metals and oxidation of the nitrogen monoxide is performed in such a way that the exhaust gas contains 30 to 70 vol. % of nitrogen dioxide before contact with the reduction catalyst.read more
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References
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Method for reduction of nitrogen oxides with ammonia using promoted zeolite catalysts
TL;DR: In this paper, a method comprising passing through a zeolite catalyst, a gaseous stream containing nitrogen oxides, ammonia and oxygen to selectively catalyze the reduction of nitrogen oxide and oxidize the excess of unreacted ammonia with oxygen to hydrogen and water is described.
Patent
System for nox reduction in exhaust gases
TL;DR: In this article, a system for NOx reduction in combustion gases, especially from diesel engines, incorporates an oxidation catalyst to convert at least a portion of NO to NO2, a particulate filter, a source of reductant such as NH3, and an SCR catalyst.
Patent
Plasma-assisted catalytic reduction system
TL;DR: In this article, the authors proposed a two-stage catalyst consisting of an oxidizing stage (100) and a reductive second stage (104), where the first stage is intended to convert NO to NO2 in the presence of O2.
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Abatement of NOx in exhaust gases
Sowmithri Krishnamurthy,John P. McWilliams,David A. Pappal,Catherine Teague Sigal,Thomas R. Kiliany +4 more
TL;DR: In this article, the reduction of nitrogen oxides with ammonia in the presence of a catalyst comprising a porous crystalline siliceous solid such as a ZSM-5 type zeolite is discussed.
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Process for removal of nox from fluid streams
TL;DR: In this article, a process and apparatus for removing nitrogen oxides from a gas stream is described, which is characterized by passing the gas stream through a first catalytic zone in the absence of added ammonia and in the presence of an oxidation catalyst to convert the NO content thereof to NO 2.