| 摘要 |
PURPOSE:To produce phthalic anhydride by introducing a mixture of o-xylene with naphthalene and a molecular oxygen-containing gas into a catalyst layer and carrying out the catalytic vapor-phase oxidation. CONSTITUTION:The objective method for catalytically oxidizing a mixture of o-xylene with naphthalene and producing phthalic anhydride is characterized by laminating a catalyst prepared by supporting a catalytic substance containing vanadium oxide, a specific anatase type titanium oxide, Nb, P, Sb and K and at least one selected from the group consisting of K, Cs, Rb an Tl on an inert carrier as a catalyst in the former stage to a catalyst similar to that in the former stage except that at least one component of the K, Cs, Rb, Tl, etc., is regulated to 17-63 wt.% expressed in terms of oxides based on the catalyst in the former stage as a catalyst in the latter stage, filling the laminated catalyst to a prescribed layer height in a reactor and passing the mixture of o- xylene with naphthalene and a molecular oxygen-containing gas through this reactor at 300-450 deg.C temperature. |
