Inorganic Microporous Membranes for Gas Separation in Fossil Fuel ...

4 Results and discussion
In pure TiO2, the anatase phase transforms partly to the rutile phase if the calcination
temperature is increased from 500 to 600ºC (Figure 59-B). Apparently, this phase
transformation is already suppressed by the presence of 10 mol % ZrO2. These results
confirm the incorporation of ZrO2 into the TiO2 framework found in literature, 83,112 up to
25 mol % ZrO2 might be dissolvable into anatase TiO2. The hydraulic radius decrease 112
and the broadening of the anatase (110) diffraction peak from 0 to 10 mol% ZrO2 doped
TiO2 clearly indicate retardation of TiO2 densification.
The TG and DTA results of the binary oxides are complex due to gradual organic loss in
a broad temperature range with many exothermic peaks, results not shown. A large
weight loss 50% is observed for these binary oxides in the temperature range of 100-
500ºC and might have masked the endothermic peak of phase transformation. A more
detailed DTA curve can be prepared by applying a long dwell time at temperatures below
the crystallisation temperature.
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