High surface area graphite sample

Figure 5.17 Reversible amount of hydrogen (electrochemical measurement at 298 K) versus the BET surface area (circles) of a few carbon nanotube samples including two measurements on high surface area graphite (HSAC) samples...

Guerrero-Ruiz et al. [139] have studied the catalytic behaviour of ruthenium for the conversion of -hexane when supported on non-reducible carriers such as activated carbon and high-surface-area graphite. The samples were also characterized by microcalorimetry of CO adsorption. The higher initial heat of CO adsorption observed for ruthenium/graphite (135 kJ mol ) compared to ruthenium/activated carbon (115 kJ mol ) indicates an enhanced electron density of the ruthenium particles caused by electron transfer from the graphite. The catalytic results show that ruthenium particles with an increased electron density have a higher activity for -hexane conversion. 

Various forms of carbon are used to sample those analytes whose breakthrough volume is too low on Tenax for sufficient preconcentration [8,395-399]. Charcoal, graphitized carbon blacks, and ceurbosieves with wface areas from 5 to 900 w /g are commercially availablJ Bhe high surface area sorbents are used... 

Graphon black, kindly furnished by the Cabot Corporation, was the adsorbent and its physical properties are listed in Table I. The term Graphon refers to Spheron 6 which had been heated to 2,700°-3,200°C. This graphitized nonporous carbon black is a unique form of carbon with uniform surface and high surface area. The Graphon samples were dried for 12 hrs. at 140°C. and stored in vacuo before use in the adsorption experiments. 

Fig. 32. Desorbed amount of hydrogen versus the BET specific surface area for carbon nanotubes and high sur ce area graphite samples [123], Reprinted with permission fiom A. ZUttel, P. Sudan, P. Mauran, T. Kioyob ashi, Cimmenegger, and L. Schlapbach, InL J. Hydrogen Enei , 27 (2002). 203.

The effect of pH of the sample, eluent flow rate, and the amount of silica on sorption and elution experimental parameters were investigated by a new phase, which was synthesized from a high surface area silica gel with a 3-trimethoxysilyl-l-propanol group. In addition, both batch and column techniques were applied to identify the characteristics of this modified silica and its application to the preconcentration and separation of Co and Ni prior to determination by graphite furnace atomic absorption spectrometry (GFAAS). ""... 

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