Thermal Analysis of V-Mo Oxides and Catalysts

Abstract

Vanadium-molybdenum oxide system and catalysts, containing ca 0, 30 and 70% of V⁴⁺ ions, without promofcors and with phosphorus, nickel and alkaline metals promotors were investigated by means of DTA, TG and X-ray diffraction. The weak effect of interaction of vanadium /V/ and molybdenum /VI/ oxides was stated at the beginning of melting temperature by means of DTA and TG.Phosphorus and nickel promotors with V-Mo oxide system neither form new phases nor influence practically on melting temperature of the system, while alkaline metals with V-Mo oxides form new phases analogical to beta vanadium bronzes. The melting temperatures of the new phases decrease with the increase of atomic mass of alkaline metal from 670°C for V-Mo-0 to 630°C for V-Mo-Li-0, and to 570°C for V-Mo-Cs-0.