Defined vanadium phosphorus oxides and their use as highly effective catalysts in ammoxidation of methyl aromatics

• Published in: Catalysis today 2003-02, Vol.78 (1), p.311-317
• Main Authors: Martin, Andreas, Narayana Kalevaru, V., Lücke, Bernhard
• Format: Article
• Language: English
• Subjects: Ammoxidation; Catalysis; Catalytic reactions; Chemistry; Exact sciences and technology; General and physical chemistry; In situ-techniques; Nitriles; Substituted methyl aromatics; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Vanadium phosphorus oxide catalysts
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/S0920-5861(02)00312-7

The heterogeneous catalytic ammoxidation of methyl aromatics and methyl hetero aromatics is a preferred method for the synthesis of aromatic and hetero aromatic nitriles. The resulting nitriles are valuable intermediates for the production of dyestuffs, pesticides, pharmaceuticals and other chemical products. Usually, the ammoxidation is carried out using V-containing oxides (e.g. V/Ti, V/Sn, V/Mo) promoted by further transition metals as catalysts. However, we have shown recently that defined vanadium phosphates (VPO) revealed an excellent ammoxidation performance. The ammoxidation of toluene was used as model reaction. An intense characterisation of some VPO catalysts under pre-treatment and working conditions by the use of various in situ-methods has thrown more light in formation and stability of the used VPO solids as well as the effect of different reactants (ammonia, toluene) on VPO surface and bulk properties.