| 초록 |
Spectrochemical analysis of a Westvaco SA30 pure activated carbon represents that sodium atoms included in the carbon-supported Pt, designated to Pt/C-W might be causing a large amount of untitratable O2 adsorption (195±2 μmol O2/g) on the catalyst at 300K, since the pure carbon possessed relatively small amount of irreversible oxygen adsorption. The adsorption capability, determined gravimetrically, of the carbon for O2 and CO adsorption at 300K was consistent with that revealed volumetrically. Carbon-supported Pt using a Norit SX1 activated carbon was well behaved for H2, O2 and CO adsorption at 300K; however, adsorption behavior was significantly dependent on the pretreatment procedure. The Pt dispersion for 3% Pt/C-N reduced at 473 K was relatively consistent, irrespective of the catalyst pretreatment condition, except for pretreatment I, and surface Pt values of 69.4 to 77.8 μmol Pts/g were obtained with H2 and O2 chemisorption as well as with cyclic O2/H2 titrations. The value for Pt dispersion by O2 adsorption at 300K was somewhat higher for 3% Pt/C-N after pretreatment III with N2O at 363K. |
