抄録
Catalytic effects of SnO2 and PbO on gasification of carbon under high pressures of CO2 were investigated by means of thermogravimetry (TG), temperature-programmed X-ray diffraction (TPXRD), and scanning electron microscopy (SEM).
Carbon material used was char from phenol-formaldehyde resin. It was mixed each metal oxide of 0.5 atomic % in a mortar grinder for 1 hour.
Nonisothermal TG measurements indicated that these oxides had high catalytic activities but SnO2 was suprrior to PbO in the activity. It was found from TPXRD at the gasification regions that both oxides in the char could coexist together with their metals more easily with increasing of CO2 pressure. According to the observation of SEM, SnO2 was inclined to disperse highly with increase of pressure while it was not seen for PbO.
Such results support the opinion that although either SnO2 or PbO will show the catalytic effect owing to the oxidation-reduction cyclic mechanism, their different activities will depend on the differences in the dispersion on the char.
