| abstract |
Catalyst capable of providing long-term stable operation and high yield of final product by reducing by-products of aromatic compounds, which are high boiling compounds, and direct-coupled two-stage catalytic gas phase using the same An oxidation method is provided. The catalyst contains molybdenum, bismuth, iron, and an alkali metal as essential components, has an atomic ratio of alkali metal to molybdenum of 12 atoms of more than 0.3 and less than 1.0, and has a high temperature side obtained by ammonia thermal desorption method. Is not more than 0.026 mmol / g. |