Application of ammonia intermittent temperature-programmed desorption to evaluate surface acidity of tungsten oxide supported on activated carbon.
Intermittent temperature-programmed desorption of ammonia was used to study the strength and population of surface acid sites of tungsten oxide supported on activated carbon pretreated at 350 and 700 degrees C. Catalysts pretreated at 350 degrees C showed two types of surface acid sites and desorption occurred with free readsorption until a temperature of around 300 degrees C was reached. Pretreatment at 700 degrees C produced three different states of ammonia adsorbed on the catalysts and desorption occurred with free readsorption.
Alvarez-Merino
M A
MA
Departamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071 Jaén, Spain.
Joly
J P
JP
Carrasco-Marín
F
F
Moreno-Castilla
C
C