Thermally stable catalyst carriers

R. Gauguin, M. Graulier and D. Pappee, Thermally Stable Carriers, Catalysts for Control of Automotive Pollutants, Ed. J. E. McEvoy, ACS Series 143, American Chemical Society, Washington D.C., 1975, pp 147-160. 

The need to employ very small particles to secure high dispersion, with their irritating habit of sintering, poses a major problem in the design of a technically usable metal catalyst. Fortunately it has been resolved by the simple expedient of affixing the particles to a thermally stable material usually known as a support, but sometimes a carrier. The following statement has been offered" as a definition and statement of the scope of the resulting substance. 

Stabilization of titania and of catalysts with vanadia contents less than 10 wt % is achieved by adding sulfuric acid to the solutions. Evaporation and calcination at 350 C forms Ti02 (anatase), vanadium and vanadium-tungsten containing catalysts with lower BET surface area (40 - 65 m /g) than the values reported above. However, the calcination at 450 °C, originally proposed as a test for thermal stability and normally accompanied by loss of surface area due to the sintering of the anatase carrier, now increases the surface area and forms stable carriers and catalysts with surface areas in the range of 80 to 90 m /g. 

---