TITLE

Influence of Rare-Earth and Bimetallic Promoters on Various VPO Catalysts for Partial Oxidation of n-Butane

AUTHOR(S)
Rownaghi, Ali Asghar; Taufiq-Yap, Yun Hin; Rezaei, Fateme
PUB. DATE
July 2009
SOURCE
Catalysis Letters;Jul2009, Vol. 130 Issue 3/4, p504
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Vanadium phosphorous oxide (VPO) catalyst was prepared using dihydrate method and tested for the potential use in selective oxidation of n-butane to maleic anhydride. The catalysts were doped by La, Ce and combined components Ce + Co and Ce + Bi through impregnation. The effect of promoters on catalyst morphology and the development of acid and redox sites were studied through XRD, BET, SEM, H2-TPR and TPRn reaction of n-butane/He. Addition of rare-earth element to VPO formulation and drying of catalyst precursor by microwave irradiation increased the fall width at half maximum (FWHM) and reduced the crystallite size of the Vanadyl hydrogen phosphate hemihydrate (VOHPO4 · 1/2 H2O, VHP) precursor phase and thus led to the production of final catalysts with larger surface area. The Ce doped VPO catalyst which, assisted by the microwave heating method, exhibited the highest surface area. Moreover, the addition of promoters significantly increased catalyst activity and selectivity as compared to undoped VPO catalyst in the oxidation reaction of n-butane. The H2-TPR and TPRn reaction profiles showed that the highest amount of active oxygen species, i.e., the V4+–O− pair, was removed from the bimetallic (Ce + Bi) promoted catalyst. This pair is responsible for n-butane activation. Furthermore, based on catalytic test results, it was demonstrated that the catalyst promoted with Ce and Bi (VPOD1) was the most active and selective catalyst among the produced catalysts with 52% reaction yield. This suggests that the rare earth metal promoted vanadium phosphate catalyst is a promising method to improve the catalytic properties of VPO for the partial oxidation of n-butane to maleic anhydride.
ACCESSION #
42211273

 

Related Articles

  • Dependence of n-Butane Activation on Active Site of Vanadium Phosphate Catalysts. Taufiq-Yap, Y. H.; Goh, C. K.; Hutchings, G. J.; Dummer, N.; Bartley, J. // Catalysis Letters;Jul2009, Vol. 130 Issue 3/4, p327 

    The nature and the role of oxygen species and vanadium oxidation states on the activation of n-butane for selective oxidation to maleic anhydride were investigated. Bi–Fe doped and undoped vanadium phosphate catalysts were used a model catalyst. XRD revealed that Bi–Fe mixture...

  • Hydrocarbon Selective Oxidation on Vanadium Phosphorus Oxide Catalysts: Insights from Electronic Structure Calculations. Thompson, Damien; Hodnett, B. K. // Topics in Catalysis;Nov2008, Vol. 50 Issue 1-4, p116 

    The ability of the vanadium phosphorus oxide (VPO) catalyst to selectively activate n-butane and then perform subsequent selective oxidation to maleic anhydride was investigated using electronic structure calculations. Both active site cluster models and periodic surface models, including...

  • A Thermodynamic Investigation of the Redox Properties of VPO Catalysts. Bakhmutsky, Kevin; Alsous, Jasmin; Gorte, Raymond // Catalysis Letters;May2012, Vol. 142 Issue 5, p578 

    The redox properties of a vanadium phosphorus oxide (VPO) catalyst with a V:P ratio of one were investigated using Coulometric Titration at 873 K. Equilibrium between (VO)PO and VOPO exists at a P(O) of 3 × 10 atm, corresponding to Δ G of −60 kJ/mol O. This value for VPO is...

  • Ordered Mesostructured Mixed Metal Oxides: Microporous VPO Phases for n-Butane Oxidation to Maleic Anhydride. Carreon, Moises A.; Guliants, Vadim V.; Pierelli, Francesca; Cavani, Fabrizio // Catalysis Letters;Jan2004, Vol. 92 Issue 1/2, p11 

    High surface area (∼250 m2/g) microporous VPO phases were prepared from the VPO/surfactant mesophases by a two-step postsynthesis treatment, consisting of a Soxhlet extraction and thermal activation in reducing atmosphere at 400 °C. The resultant microporous VPO phases were studied in...

  • The dilution of vanadyl pyrophosphate, catalyst for n-butane oxidation to maleic anhydride, with aluminum phosphate: unexpected reactivity due to the contribution of the diluting agent. Cavani, F.; Cortelli, C.; Frattini, A.; Puccinotti, G.; Ricotta, M.; Rodeghiero, F.; Trifirò, F.; Fumagalli, C.; Mazzoni, G. // Topics in Catalysis;Jun2006, Vol. 38 Issue 4, p295 

    This paper describes the preparation, characterization and reactivity in n-butane oxidation of catalysts made of vanadyl pyrophosphate (VPP) diluted in aluminum phosphate. Catalysts were prepared by synthesizing at the same time the VPP precursor and AlPO4, in order to develop mixed systems,...

  • Preparation of Novel Composite VPO/Fumed Silica Catalyst for Partial Oxidation of n-Butane. Zhou, Z. Q.; Xu, H. Y.; Ji, W. J.; Chen, Y. // Catalysis Letters;Jul2004, Vol. 96 Issue 3/4, p221 

    By applying fumed SiO2 and the deposition–precipitation method based on organic medium, the composite VPO/fumed SiO2 catalysts were first prepared and tried for partial oxidation of n-butane to maleic anhydride. In the temperature range of 653–693 K the fumed SiO2-based catalysts...

  • BIMEVOX materials for application in SOFCS. CHMIELOWIEC, J.; PAŚCIAK, G.; BUJŁO, P. // Materials Science (0137-1339);2009 Part 1 of 2, Vol. 27 Issue 4, p1251 

    Presented work concerns BIMEVOX (bismuth metal vanadium oxide) based solid electrolytes doped with rare earth elements (lanthanum). Investigations of melting point and compositions of elaborated materials were performed with the DTA and X-ray measurements. For determination of conductivities,...

  • Preparation, Characterization and Catalytic Activity of MgO/SiO Supported Vanadium Oxide Based Catalysts. Aboelfetoh, Eman; Pietschnig, Rudolf // Catalysis Letters;Jan2014, Vol. 144 Issue 1, p97 

    Vanadium oxide-based catalyst obtained by grafting VOCl on Florisil (MgO:SiO) with the molar ratio of 15:85 have been studied for the selective oxidation of cyclohexane in order to obtain cyclohexyl hydroperoxide, cyclohexanol and cyclohexanone. The performances obtained have been compared with...

  • Partial Oxidation of n-Butane over a Sol-Gel Prepared Vanadium Phosphorous Oxide. Salazar, Juan M.; Hohn, Keith L. // Catalysts (2073-4344);Mar2013, Vol. 3 Issue 1, p11 

    Vanadium phosphorous oxide (VPO) is traditionally manufactured from solid vanadium oxides by synthesizing VOHPCvO.SH^O (the precursor) followed by in situ activation to produce (VO)2P2O7 (the active phase). This paper discusses an alternative synthesis method based on sol-gel techniques....

Share

Read the Article

Courtesy of NEW JERSEY STATE LIBRARY

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics