Oxidation of 1-butene on Vsub(2)Osub(5)-Psub(2)Osub(5)-Lnsub(2)Osub(3) catalyst Pt. 2

The air oxidation of 1-butene was carried out over various V-P-O-Ln (where Ln=Nd, Sm) oxide catalysts. The P/V atomic ratio was fixed (the value of P/V = 1.6 was chosen), but the Ln/V atomic ratio ranged from 0 to 0.30. The highest activities and selectivities were obtained in the case of the V-P-O-Ln catalysts with Ln/V of 0.06. The neodymium containing system shows slightly higher selectivity for maleic anhydride than the one containing samarium. A good correlation was found between acidity of the catalysts and the average oxidation state of vanadium as well as between acidity and selectivity to maleic anhydride. (author)