skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Influence of catalyst synthesis method on selective catalytic reduction (SCR) of NO by NH3 with V2O5-WO3/TiO2 catalysts

Journal Article · · Applied Catalysis. B, Environmental
 [1];  [2];  [2];  [3];  [4];  [4];  [2]
  1. Chongqing Univ., Chongqing (China). College of Materials Science and Engineering; Lehigh Univ., Bethlehem, PA (United States). Operando Molecular Spectroscopy & Catalysis Lab.
  2. Lehigh Univ., Bethlehem, PA (United States). Operando Molecular Spectroscopy & Catalysis Lab.
  3. Chongqing Univ., Chongqing (China). College of Materials Science and Engineering
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Science Division and Center for Nanophase Materials Sciences

We compared the molecular structures, surface acidity and catalytic activity for NO/NH3/O2 SCR of V2O5-WO3/TiO2 catalysts for two different synthesis methods: co-precipitation of aqueous vanadium and tungsten oxide precursors with TiO(OH)2 and by incipient wetness impregnation of the aqueous precursors on a reference crystalline TiO2 support (P25; primarily anatase phase). Bulk analysis by XRD showed that co-precipitation results in small and/or poorly ordered TiO2(anatase) particles and that VOx and WOx do not form solid solutions with the bulk titania lattice. Surface analysis of the co-precipitated catalyst by High Sensitivity-Low Energy Ion Scattering (HS-LEIS) confirms that the VOx and WOx are surface segregated for the co-precipitated catalysts. In situ Raman and IR spectroscopy revealed that the vanadium and tungsten oxide components are present as surface mono-oxo O = VO3 and O = WO4 sites on the TiO2 supports. Co-precipitation was shown for the first time to also form new mono-oxo surface VO4 and WO4 sites that appear to be anchored at surface defects of the TiO2 support. IR analysis of chemisorbed ammonia showed the presence of both surface NH3* on Lewis acid sites and surface NH4+* on Brønsted acid sites. TPSR spectroscopy demonstrated that the specific SCR kinetics was controlled by the redox surface VO4 species and that the surface kinetics was independent of TiO2 synthesis method or presence of surface WO5 sites. SCR reaction studies revealed that the surface WO5 sites possess minimal activity below ~325 °C and their primary function is to increase the adsorption capacity of ammonia. A relationship between the SCR activity and surface acidity was not found. The SCR reaction is controlled by the surface VO4 sites that initiate the reaction at ~200 °C. The co-precipitated catalysts were always more active than the corresponding impregnated catalysts. Finally, we ascribe the higher activity of the co-precipitated catalysts to the presence of the new surface WOx sites associated surface defects on the TiO2 support that increase the ammonia adsorption capacity.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Energy Frontier Research Centers (EFRC) (United States). Center for Understanding and Control of Acid Gas-induced Evolution of Materials for Energy (UNCAGE-ME)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
AC05-00OR22725; SC0012577; 51274263; 51204220; UNCAGE-ME
OSTI ID:
1295102
Alternate ID(s):
OSTI ID: 1341096
Journal Information:
Applied Catalysis. B, Environmental, Vol. 193, Issue C; ISSN 0926-3373
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 106 works
Citation information provided by
Web of Science

References (64)

Surface and catalytic properties of Vanadia-Titania and Tungsta-Titania systems in the Selective Catalytic Reduction of nitrogen oxides journal May 1993
Chemical and mechanistic aspects of the selective catalytic reduction of NO by ammonia over oxide catalysts: A review journal September 1998
Present status and perspectives in de-NOx SCR catalysis journal December 2001
Recent Advances in De‐NOxing Catalysis for Stationary Applications journal March 1996
Effect of operating variables on the enhanced SCR reaction over a commercial V2O5–WO3/TiO2 catalyst for stationary applications journal April 2012
Reactivity and Physicochemical Characterization of V2O5-WO3/TiO2 De-NO Catalysts journal August 1995
WO3–TiO2 monolithic catalysts for high temperature SCR of NO by NH3: Influence of preparation method on structural and physico-chemical properties, activity and durability journal March 2007
Systematic mechanism study of the high temperature SCR of NO by NH3 over a W/TiO2 catalyst journal September 2012
The effect of metal oxide additives on the activity of V2O5/TiO2 catalysts for the selective catalytic reduction of nitric oxide by ammonia journal February 1999
Reactivity of V2O5Catalysts for the Selective Catalytic Reduction of NO by NH3: Influence of Vanadia Loading, H2O, and SO2 journal June 1996
Preparation and properties of vanadia/titania monolayer catalysts journal September 1997
Effect of vanadia and tungsten loadings on the physical and chemical characteristics of V2O5-WO3/TiO2 catalysts journal February 2004
Study of anatase–rutile transition phase in monolithic catalyst V2O5/TiO2 and V2O5–WO3/TiO2 journal February 2001
Thermal stability of vanadia-tungsta-titania catalysts in the SCR process journal November 2002
Study of thermal deactivation of a de-NOx commercial catalyst journal December 2001
Vanadia/Titania Catalysts for Selective Catalytic Reduction (SCR) of Nitric-Oxide by Ammonia journal January 1995
Vanadia-Titania Catalysts for Selective Catalytic Reduction of Nitric-Oxide by Ammonia journal January 1995
Selective Catalytic Reduction of NO with NH3 on SO−24/TiO2 Superacid Catalyst journal January 1993
Fundamental Studies of Butane Oxidation over Model-Supported Vanadium Oxide Catalysts: Molecular Structure-Reactivity Relationships journal August 1997
Acidic properties and stability of sulfate-promoted metal oxides journal February 1992
Structural determination of supported vanadium pentoxide-tungsten trioxide-titania catalysts by in situ Raman spectroscopy and x-ray photoelectron spectroscopy journal November 1991
Monitoring surface metal oxide catalytic active sites with Raman spectroscopy journal January 2010
Structure and Catalytic Properties of Supported Vanadium Oxides: Support Effects on Oxidative Dehydrogenation Reactions journal January 1999
Laser Raman spectroscopy of supported vanadium oxide catalysts journal May 1990
A new view on the relations between tungsten and vanadium in V2O5WO3/TiO2 catalysts for the selective reduction of NO with NH3 journal February 2012
Effect of grafting sequence on the behavior of titania-supported v VO-WO catalysts in the selective reduction of NO by NH journal June 2000
Vanadia and tungsta grafted on TiO2: influence of the grafting sequence on structural and chemical properties journal May 2000
Vanadia grafted on TiO2–SiO2, TiO2 and SiO2 aerogels Structural properties and catalytic behaviour in selective reduction of NO by NH3 journal November 1999
Study of synthesis and catalytic property of WO3/TiO2 catalysts for NO reduction at high temperatures journal November 2011
Flame-made WO3/TiO2 nanoparticles: Relation between surface acidity, structure and photocatalytic activity journal February 2008
Quantitative relationship between the nature of surface species and the catalytic activity of tungsten oxides supported on crystallized titania journal March 2010
Influence of calcination treatment on the structure of grafted WOx species on titania journal February 1999
Relations between Structure, Acidity, and Activity of WO x /TiO 2 :  Influence of the Initial State of the Support, Titanium Oxyhydroxide, or Titanium Oxide journal November 2006
Conversion of 1-butene over WO3-TiO2 Catalysts journal January 1994
Preparation of selective catalytic reduction catalysts via milling and thermal spreading journal November 1997
Anomalous reactivity of supported V2O5 nanoparticles for propane oxidative dehydrogenation: influence of the vanadium oxide precursor journal January 2013
Recommendations for the characterization of porous solids (Technical Report) journal January 1994
Physical and chemical characterization of surface vanadium oxide supported on titania: influence of the titania phase (anatase, rutile, brookite and B) journal November 1992
Tuning the Electronic and Molecular Structures of Catalytic Active Sites with Titania Nanoligands journal January 2009
Oxide phonon spectra journal January 1969
Vibrational spectra of alumina- and silica-supported vanadia revisited: An experimental and theoretical model catalyst study journal August 2004
CH3OH oxidation over well-defined supported V2O5/Al2O3 catalysts: Influence of vanadium oxide loading and surface vanadium–oxygen functionalities journal April 2008
Structural Determination of Bulk and Surface Tungsten Oxides with UV−vis Diffuse Reflectance Spectroscopy and Raman Spectroscopy journal September 2007
Catalysis science of the solid acidity of model supported tungsten oxide catalysts journal August 2006
Structure of Vanadium Oxide Supported on Ceria by Multiwavelength Raman Spectroscopy journal December 2011
Differentiation of mono-oxo and polyoxo and of monomeric and polymeric vanadate, molybdate and tungstate species in metal oxide catalysts by IR and Raman spectroscopy journal January 2002
Effects of CeO2 support facets on VOx/CeO2 catalysts in oxidative dehydrogenation of methanol journal June 2014
Reactivity of V2O5-WO3/TiO2 catalysts in the selective catalytic reduction of nitric oxide by ammonia journal May 1996
An FT-IR study of ammonia adsorption and oxidation over anatase-supported metal oxides journal September 1997
Dynamics of the SCR-DeNOx reaction by the transient-response method journal October 1997
Characterization of tungsta-titania catalysts journal July 1992
Acidic properties of supported niobium oxide catalysts: An infrared spectroscopy investigation journal May 1992
Selective Catalytic Reduction of Nitric Oxide by Ammonia over V 2 O 5 /TiO 2 , V 2 O 5 /TiO 2 /SiO 2 , and V 2 O 5 −WO 3 /TiO 2 Catalysts:  Effect of Vanadia Content on the Activation Energy journal January 1996
Comparison and analysis of intrinsic kinetics and effectiveness factors for the catalytic reduction of nitrogen oxide (NO) with ammonia in the presence of oxygen journal April 1992
STAFF-INDUSTRY COLLABORATIVE REPORT Vapor-Phase Production of Colloidal Silica journal March 1959
Resolving the Atomic Structure of Vanadia Monolayer Catalysts: Monomers, Trimers, and Oligomers on Ceria journal October 2009
Molecular/electronic structure–surface acidity relationships of model-supported tungsten oxide catalysts journal March 2007
Reaction-Induced Spreading of Metal Oxides onto Surfaces of Oxide Supports during Alcohol Oxidation:  Phenomenon, Nature, and Mechanisms journal February 1999
Steady-State and Transient Reactivity Study of TiO 2 -Supported V 2 O 5 −WO 3 De-NO x Catalysts:  Relevance of the Vanadium−Tungsten Interaction on the Catalytic Activity journal January 1996
An EPR Study of the Surface Chemistry of the V2O5–WO3/TiO2Catalyst: Redox Behaviour and State of V(IV) journal March 1997
Recent conceptual advances in the catalysis science of mixed metal oxide catalytic materials journal February 2005
Oxidation of SO2over Supported Metal Oxide Catalysts journal January 1999
The effects of structure on the catalytic activity and selectivity of V2O5/TiO2 for the reduction of NO by NH3 journal April 1992
Selective catalytic reduction of nitric oxide over vanadia grafted on titania. Influence of vanadia loading on structural and catalytic properties of catalysts journal January 1992

Cited By (15)

Insights over Titanium Modified FeMgOx Catalysts for Selective Catalytic Reduction of NOx with NH3: Influence of Precursors and Crystalline Structures journal June 2019
TiO 2 –SiO 2 supported MnWO x catalysts by liquid-phase deposition for low-temperature NH 3 -SCR journal January 2019
DFT and experimental study on denitration mechanism over VPO/TiO2 catalyst journal February 2019
Comprehensive study of the promotional mechanism of F on Ce–Mo/TiO 2 catalysts for wide temperature NH 3 -SCR performance: the activation of surface Ti–F bonds journal January 2019
A zeolitic vanadotungstate family with structural diversity and ultrahigh porosity for catalysis journal September 2018
Low-temperature co-purification of NOx and Hg0 from simulated flue gas by CexZryMnzO2/r-Al2O3: the performance and its mechanism journal May 2018
The remarkable promotional effect of Sn on CeVO 4 catalyst for wide temperature NH 3 -SCR process by citric acid-assisted solvothermal synthesis and post-hydrothermal treatment journal January 2018
Alkali-driven active site shift of fast SCR with NH 3 on V 2 O 5 –WO 3 /TiO 2 catalyst via a novel Eley–Rideal mechanism journal January 2019
Thermal stability of Si-doped V2O5/WO3–TiO2 for selective catalytic reduction of NOx by NH3 journal December 2018
One-pot synthesis of framework W-doped TS-1 zeolite with robust Lewis acidity for effective oxidative desulfurization journal January 2019
Simultaneous removal of SO 2 and NO x from flue gas by wet scrubbing using a urea solution journal March 2018
Research Status and Prospect on Vanadium-Based Catalysts for NH3-SCR Denitration journal September 2018
Mechanism by which Tungsten Oxide Promotes the Activity of Supported V 2 O 5 /TiO 2 Catalysts for NO X Abatement: Structural Effects Revealed by 51 V MAS NMR Spectroscopy journal September 2019
Effect of Ag–Fe–Cu tri-metal loading in bismuth oxybromide to develop a novel nanocomposite for the sunlight driven photocatalytic oxidation of alcohols journal January 2019
Mechanism by which Tungsten Oxide Promotes the Activity of Supported V 2 O 5 /TiO 2 Catalysts for NO X Abatement: Structural Effects Revealed by 51 V MAS NMR Spectroscopy journal July 2019