Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
Novel bifunctional catalysts combining two active phases, typically Cu-ZSM-5 and a modifier, were prepared and tested for the selective catalytic reduction of nitrogen oxides using propylene in order to overcome the hindering effects of water typically seen for single-phase catalysts such as Cu-ZSM-5. The catalysts were made by typical preparation techniques, but parameters could be varied to influence the catalyst. The physical characterization of the materials showed that the modification phase was added strictly to the external surface of the zeolite without hindering any internal surface area. Chemical characterization by temperature programmed reactions, DRIFTS and x-ray absorption spectroscopy indicated strong interaction between the two phases, primarily producing materials that exhibited lower reduction temperatures. Two improvements in NOx reduction activity (1000 ppm NO, 1000 ppm C3H6, 2% O2, 30,000 hr-1 GHSV) were seen for these catalysts compared with Cu- ZSM-5: a lower temperature of maximum NOx conversion activity (as low at 250 C), and an enhancement of activity when water was present in the system. The use of a second phase provides a way to further tune the properties of the catalyst in order to achieve mechanistic conditions necessary to maximize NOx remediation.
BIFUNCTIONAL CATALYSTS FOR THE SELECTIVE CATALYTIC REDUCTION OF NO BY HYDROCARBONS.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
Novel bifunctional catalysts combining two active phases, typically Cu-ZSM-5 and a modifier, were prepared and tested for the selective catalytic reduction of nitrogen oxides using propylene in order to overcome the hindering effects of water typically seen for single-phase catalysts such as Cu-ZSM-5. The catalysts were made by typical preparation techniques, but parameters could be varied to influence the catalyst. The physical characterization of the materials showed that the modification phase was added strictly to the external surface of the zeolite without hindering any internal surface area. Chemical characterization by temperature programmed reactions, DRIFTS and x-ray absorption spectroscopy indicated strong interaction between the two phases, primarily producing materials that exhibited lower reduction temperatures. Two improvements in NOx reduction activity (1000 ppm NO, 1000 ppm C3H6, 2% O2, 30,000 hr-1 GHSV) were seen for these catalysts compared with Cu- ZSM-5: a lower temperature of maximum NOx conversion activity (as low at 250 C), and an enhancement of activity when water was present in the system. The use of a second phase provides a way to further tune the properties of the catalyst in order to achieve mechanistic conditions necessary to maximize NOx remediation.
Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
Novel bifunctional catalysts combining two active phases, typically Cu-ZSM-5 and a modifier, were prepared and tested for the selective catalytic reduction of nitrogen oxides using propylene in order to overcome the hindering effects of water typically seen for single-phase catalysts such as Cu-ZSM-5. The catalysts were made by typical preparation techniques, but parameters could be varied to influence the catalyst. The physical characterization of the materials showed that the modification phase was added strictly to the external surface of the zeolite without hindering any internal surface area. Chemical characterization by temperature programmed reactions, DRIFTS and x-ray absorption spectroscopy indicated strong interaction between the two phases, primarily producing materials that exhibited lower reduction temperatures. Two improvements in NOx reduction activity (1000 ppm NO, 1000 ppm C3H6, 2% O2, 30,000 hr-1 GHSV) were seen for these catalysts compared with Cu- ZSM-5: a lower temperature of maximum NOx conversion activity (as low at 250 C), and an enhancement of activity when water was present in the system. The use of a second phase provides a way to further tune the properties of the catalyst in order to achieve mechanistic conditions necessary to maximize NOx remediation.
Selective Catalytic Reduction of Nitric Oxide with Methane on Bifunctional Zeolite Catalysts
Author: Masaru Ogura
Publisher:
ISBN:
Category :
Languages : en
Pages : 171
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 171
Book Description
Selective Catalytic Reduction of NOx
Author: Oliver Kröcher
Publisher: MDPI
ISBN: 3038973645
Category : Science
Languages : en
Pages : 281
Book Description
This book is a printed edition of the Special Issue "Selective Catalytic Reduction of NOx" that was published in Catalysts
Publisher: MDPI
ISBN: 3038973645
Category : Science
Languages : en
Pages : 281
Book Description
This book is a printed edition of the Special Issue "Selective Catalytic Reduction of NOx" that was published in Catalysts
Superior Catalysts for Selective Catalytic Reduction of Nitric Oxide
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Preparation, Characterization and Deactivation of the Catalysts for the Selective Catalytic Reduction of NO with NH3
Author: Jianping Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 342
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 342
Book Description
Development of Pt/MCM-41 Catalysts for Selective Catalytic Reduction of Lean NO[x] Using Hydrocarbon
Author: Shoucang Shen
Publisher:
ISBN:
Category : Heterogeneous catalysis
Languages : en
Pages : 446
Book Description
Publisher:
ISBN:
Category : Heterogeneous catalysis
Languages : en
Pages : 446
Book Description
Plasma-assisted Catalytic Reduction of NO[sub]x[/sub].
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Many studies suggest that lean-NOx SCR proceeds via oxidation of NO to NO[not] by oxygen, followed by the reaction of the NO[not]with hydrocarbons. On catalysts that are not very effective in catalyzing the equilibration of NO+O[not] and NO[not], the rate of N[not] formation issubstantially higher when the input NOx is NO[not] instead of NO. The apparent bifunctional mechanism in the SCR ofNOx has prompted the use of mechanically mixed catalyst components, in which one component is used to accelerate theoxidation of NO to NO[not], and another component catalyzes the reaction between NO[not] and the hydrocarbon. Catalysts that previously wereregarded as inactive for NOx reduction could therefore become efficient when mixed with an oxidation catalyst. PreconvertingNO to NO[not] opens the opportunity for a wider range of SCR catalysts and perhaps improves the durability of these catalysts. This paperdescribes the use of a non-thermal plasma as an efficient means for selective partial oxidation of NO to NO[not]. When combined with sometypes of SCR catalyst, the plasma can greatly enhance the NOx reduction and eliminate some of the deficiencies encountered inan entirely catalyst-based approach. efficiency for reduction of NOsubx
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Many studies suggest that lean-NOx SCR proceeds via oxidation of NO to NO[not] by oxygen, followed by the reaction of the NO[not]with hydrocarbons. On catalysts that are not very effective in catalyzing the equilibration of NO+O[not] and NO[not], the rate of N[not] formation issubstantially higher when the input NOx is NO[not] instead of NO. The apparent bifunctional mechanism in the SCR ofNOx has prompted the use of mechanically mixed catalyst components, in which one component is used to accelerate theoxidation of NO to NO[not], and another component catalyzes the reaction between NO[not] and the hydrocarbon. Catalysts that previously wereregarded as inactive for NOx reduction could therefore become efficient when mixed with an oxidation catalyst. PreconvertingNO to NO[not] opens the opportunity for a wider range of SCR catalysts and perhaps improves the durability of these catalysts. This paperdescribes the use of a non-thermal plasma as an efficient means for selective partial oxidation of NO to NO[not]. When combined with sometypes of SCR catalyst, the plasma can greatly enhance the NOx reduction and eliminate some of the deficiencies encountered inan entirely catalyst-based approach. efficiency for reduction of NOsubx
Reformate Assisted Hydrocarbon Selective Catalytic NOx Reduction Over Silver Supported on Alumina Catalysts
Author: William L. Johnson
Publisher:
ISBN:
Category :
Languages : en
Pages : 290
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 290
Book Description
NOx Trap Catalysts and Technologies
Author: Luca Lietti
Publisher: Royal Society of Chemistry
ISBN: 1788013239
Category : Science
Languages : en
Pages : 514
Book Description
This book will be the first to comprehensively present the current research on catalysts used for NOx abatement in lean exhausts.
Publisher: Royal Society of Chemistry
ISBN: 1788013239
Category : Science
Languages : en
Pages : 514
Book Description
This book will be the first to comprehensively present the current research on catalysts used for NOx abatement in lean exhausts.
The Selective Catalytic Reduction of NO ̲x by CH3OH Under Oxidising Conditions Over Al2O3 Based Catalysts
Author: E Halpin
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description