Catalytic and Acidic Properties of Crystalline Zirconium Phosphate

Decomposition of alcohols over zirconium and titanium phosphates

“…It was also reported before that both Bronsted and Lewis acid sites were active in these reactions (Clearfield and Thakur, 1980;Clearfield and Frianeza, 1984;Gryaznova et al, 1982;Hattori et al, 1977). Hattori et al (1977) carried out propanol dehydration over -ZrP calcined at various temperatures between 300 and 800 °C. Although TGA curves EtOH to CO+ C02 0.2 1.0 2.0 0 Pressure = 1 atm; reaction temp = 350 °C; WHSV = 3.2 h"1.…”

“…It is not unexpected to observe that zirconium and titanium phosphates are very active in dehydration reactions (Clearfield and Thakur, 1980; Clearfield and Frianeza, 1984;Gryaznova et al, 1982). It was also reported before that both Bronsted and Lewis acid sites were active in these reactions (Clearfield and Thakur, 1980;Clearfield and Frianeza, 1984;Gryaznova et al, 1982;Hattori et al, 1977). Hattori et al (1977) carried out propanol dehydration over -ZrP calcined at various temperatures between 300 and 800 °C.…”

“…Upon dehydration the -ZrP, which has an interlayer spacing of 7.6 A, transforms to f-ZRP (<¿002 = 7.4 Á), and at higher temperatures, 77-ZrP, interlayer spacing 7.1 Á, is obtained (Clearfield and Pack, 1975). This interlayer distance is so small that the dehydration of cyclohexanol over zirconium phosphate was found to be catalyzed only by the surface acid groups and not those in the interior (Clearfield and Thakur, 1980;Thakur and Clearfield, 1981).…”