Catalysis and structure of the SbVO4/Sb2O4 system for propane ammoxidation

被引:57
作者
Nilsson, J [1 ]
LandaCanovas, A [1 ]
Hansen, S [1 ]
Andersson, A [1 ]
机构
[1] LUND UNIV,CTR CHEM,DEPT INORGAN CHEM 2,NATL CTR HREM,S-22100 LUND,SWEDEN
关键词
structure; SbVO4/Sb2O4; system; propane ammoxidation;
D O I
10.1016/S0920-5861(96)00110-1
中图分类号
O69 [应用化学];
学科分类号
081704 ;
摘要
Pure Sb0.9V0.9O4 and various preparations with excess of either vanadia or antimony oxide, including mechanical mixtures, have been investigated for propane ammoxidation to acrylonitrile. The catalysts were characterized before and after use in catalysis by various methods, including electron microscopy, infrared spectroscopy and XPS. The catalytic data show that preparations with approximate to SbVO4 and alpha-Sb2O4, compared with the single phases, are more selective to acrylonitrile formation on the condition that the excess antimony oxide is present while synthesising the approximate to SbVO, phase. Considering the catalytic data together with the results from the characterisations, various possibilities are discussed to explain the role of excess alpha-Sb2O4 in propane ammoxidation. Possibilities that can be excluded on rational grounds are catalysis on two phases, or, at grain boundaries, an influence on the morphology of approximate to SbVO4 from alpha-Sb2O4, the formation of alpha-Sb2O4 containing vanadium, defect formation, creation of active sites by the spillover of oxygen, and formation of VSb2O5. Instead, the observed synergy effect is due to the formation of approximate to SbVO4 enriched with antimony at the surface, creating isolation to a suitable level of the V-centres. The explanation is consistent with several observations including catalytic data for a series of vanadium compounds with different vanadium content, showing that structural isolation of the vanadium is necessary for obtaining high selectivity to acrylonitrile.
引用
收藏
页码:97 / 108
页数:12
相关论文
共 27 条
  • [1] SURFACE CHARACTERIZATION AND REACTIVITY IN AMMOXIDATION REACTIONS OF VANADIUM ANTIMONATE CATALYSTS
    ANDERSSON, A
    ANDERSSON, SLT
    CENTI, G
    GRASSELLI, RK
    SANATI, M
    TRIFIRO, F
    [J]. APPLIED CATALYSIS A-GENERAL, 1994, 113 (01) : 43 - 57
  • [2] [Anonymous], 1988, INORGANIC CRYSTAL ST
  • [3] BARTEK JP, 1989, Patent No. 4797381
  • [4] VANADIUM ANTIMONATE
    BERRY, FJ
    BRETT, ME
    PATTERSON, WR
    [J]. JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1983, (01): : 9 - 12
  • [5] OXIDATION-STATES IN VSBO4
    BIRCHALL, T
    SLEIGHT, AW
    [J]. INORGANIC CHEMISTRY, 1976, 15 (04) : 868 - 870
  • [6] BRAZDIL JR, 1989, Patent No. 4871706
  • [7] CADUS LE, 1994, STUD SURF SCI CATAL, V82, P41
  • [8] A SELECTIVITY FACTOR IN VAPOR-PHASE HYDROCARBON OXIDATION CATALYSIS
    CALLAHAN, JL
    GRASSELLI, RK
    [J]. AICHE JOURNAL, 1963, 9 (06) : 755 - 760
  • [9] CENTI G, 1990, STUD SURF SCI CATAL, V55, P515
  • [10] CENTI G, 1994, STUD SURF SCI CATAL, V82, P281