NO{sub X} REDUCTION BEHAVIOR OF ALUMINA AND ZEOLITE CATALYSTS IN COMBINATION WITH NON-THERMAL PLASMA.

NO{sub X} REDUCTION BEHAVIOR OF ALUMINA AND ZEOLITE CATALYSTS IN COMBINATION WITH NON-THERMAL PLASMA. PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 8

Book Description
Lean burn gasoline and diesel engines provide improved fuel economy when compared to engines operating under stoichiometric fuel/air conditions. At the same time, lean burn and diesel engines present a problem for emission control. Because they operate under oxidizing conditions, the conventional three-way catalyst is not effective in NOx reduction [1,2]. In addition, the wide temperature range of automobile exhaust gases present a challenge for catalyst design. The temperature of exhaust gases from a light duty diesel engine can vary from 150 to 500 C, depending on the operating conditions. To date, a catalyst that operates with high NOx conversion efficiency over the entire operating range has not been found. Non-thermal plasma assisted catalysis has been shown to be a promising technology for NOx reduction in lean burn and diesel exhaust gases [3,4]. The approach exploited in this paper is to use a plasma in combination with several catalysts, each of which are active over unique temperature ranges. It was reported in the literature, that the one of the essential roles of plasma treatment is to oxidize NO to easier reducible NO2 [7]. In this contribution, the other important function of plasma treatment, namely partial oxidation of propylene, will be demonstrated.

SELECTIVE REDUCTION OF NOX IN OXYGEN RICH ENVIRONMENTS WITH PLASMA-ASSISTED CATALYSIS

SELECTIVE REDUCTION OF NOX IN OXYGEN RICH ENVIRONMENTS WITH PLASMA-ASSISTED CATALYSIS PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 6

Book Description
The control of NOx (NO and NO2) emissions from so-called ''lean-burn'' vehicle engines remains a challenge. In recent years, there have been a number of reports that show that a plasma device combined with a catalyst can reduce as high as 90% or more of NOx in simulated diesel and other ''lean-burn'' exhaust. In the case of propylene containing simulated diesel exhaust, the beneficial role of a plasma treatment is now thought to be due to oxidation of NO to NO2, and the formation of partially oxidized hydrocarbons that are more active for the catalytic reduction of NO2 than propylene. Thus, the overall system can be most usefully described as hydrocarbon selective catalytic reduction (SCR) enhanced by 'reforming' the exhaust with a non-thermal plasma (NTP) device. For plasma-enhanced catalysis, both zeolite- and alumina-based materials have shown high activity, albeit in somewhat different temperature ranges, when preceded by an NTP reactor. This paper will briefly describe our research efforts aimed at optimizing the catalyst materials for NTP-catalysis devices based, in part, on our continuing studies of the NTP- and catalytic-reaction mechanisms. Various alkali- and alkaline earth-cation-exchanged Y zeolites have been prepared, their material properties characterized, and they have been tested as catalytic materials for NOx reduction in laboratory NTP-catalysis reactors. Interestingly, NO2 formed in the plasma and not subsequently removed over these catalysts, will back-convert to NO, albeit to varying extents depending upon the nature of the cation. Besides this comparative reactivity, we will also discuss selected synthesis strategies for enhancing the performance of these zeolite-based catalyst materials. A particularly important result from our mechanistic studies is the observation that aldehydes, formed during the plasma treatment of simulated diesel exhaust, are the important species for the reduction of NOx to N2. Indeed, acetaldehyde has been found to be especially effective in the thermal reduction of both NO and NO2 over Ba- and Na-Y zeolite catalysts.

Zeolite Catalysts in the Reduction of NO[sub X] in Lean Automotive Exhaust Gas Conditions

Zeolite Catalysts in the Reduction of NO[sub X] in Lean Automotive Exhaust Gas Conditions PDF Author:
Publisher:
ISBN: 9789514282850
Category :
Languages : en
Pages : 84

Book Description


NO[sub X] Reduction by Hydrocarbons and Hydrogen on Metal Oxide and Zeolite Based Catalysts in Lean Conditions

NO[sub X] Reduction by Hydrocarbons and Hydrogen on Metal Oxide and Zeolite Based Catalysts in Lean Conditions PDF Author: Teuvo Maunula
Publisher:
ISBN: 9789512289042
Category :
Languages : en
Pages : 129

Book Description
Tiivistelmä.

Plasma-assisted Catalytic Reduction System

Plasma-assisted Catalytic Reduction System PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description
Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.

Catalytic Air Pollution Control

Catalytic Air Pollution Control PDF Author: Ronald M. Heck
Publisher: John Wiley & Sons
ISBN: 0470275030
Category : Science
Languages : en
Pages : 548

Book Description
Catalytic Air Pollution Control: Commercial Technology is the primary source for commercial catalytic air pollution control technology, offering engineers a comprehensive account of all modern catalytic technology. This Third Edition covers all the new advances in technology in automotive catalyst control technology, diesel engine catalyst control technology, small engine catalyst control technology, and alternate sustainable fuels for auto and diesel.

Government Reports Announcements & Index

Government Reports Announcements & Index PDF Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 564

Book Description


Non-Thermal Plasma Techniques for Pollution Control

Non-Thermal Plasma Techniques for Pollution Control PDF Author: Bernie M. Penetrante
Publisher: Springer Science & Business Media
ISBN: 3642784763
Category : Science
Languages : en
Pages : 422

Book Description
Acid rain, global warming, ozone depletion, and smog are preeminent environmental problems facing the world today. Non-thermal plasma techniques offer an innovative approach to the solution of some of these problems. There are many types of non-thermal plasma devices that have been developed for environmental applications. The potential of these devices for the destruction of pollutants or toxic molecules has already been demonstrated in many contexts, such as nitrogen oxides (NOX) and sulfur dioxide (SO2) in flue gases, heavy metals and volatile organic compounds (VOCs) in industrial effluents, and chemical agents such as nerve gases. This book contains a comprehensive account of the latest developments in non-thermal plasma devices and their applications to the disposal of a wide variety of gaseous pollutants.

Natural Gas

Natural Gas PDF Author: James G. Speight
Publisher: Gulf Professional Publishing
ISBN: 0128097744
Category : Technology & Engineering
Languages : en
Pages : 465

Book Description
Natural Gas: A Basic Handbook, Second Edition provides the reader with a quick and accessible introduction to a fuel source/industry that is transforming the energy sector. Written at an introductory level, but still appropriate for engineers and other technical readers, this book provides an overview of natural gas as a fuel source, including its origins, properties and composition. Discussions include the production of natural gas from traditional and unconventional sources, the downstream aspects of the natural gas industry. including processing, storage, and transportation, and environmental issues and emission controls strategies. This book presents an ideal resource on the topic for engineers new to natural gas, for advisors and consultants in the natural gas industry, and for technical readers interested in learning more about this clean burning fuel source and how it is shaping the energy industry. Updated to include newer sources like shale gas Includes new discussions on natural gas hydrates and flow assurance Covers environmental issues Contain expanded coverage of liquefied natural gas (LNG)

Selective Oxidation of Hydrocarbons

Selective Oxidation of Hydrocarbons PDF Author: D. J. Hucknall
Publisher:
ISBN:
Category : Catalysis
Languages : en
Pages : 0

Book Description