Carbon characteristics

The state of bonding of carbon on the surface can easily be detected by AES. The carbon Auger peak shows a different fine structure for carbidic and graphitic carbon, as shown in Fig. 5a and b, respectively (32). Carbidic carbon characteristically shows three sharp peaks near 270 V the graphitic form shows a more rounded spectrum. It is therefore possible to differentiate the effects of carbidic and graphitic carbon on surface reactivity. 

O Dowd, C. D and M. H. Smith, Submicron Particle, Radon, and Soot Carbon Characteristics over the Northeast Atlantic, J. Geophys. Res., 98, 1123-1135 (1993a). 

Petrography and Carbonization Characteristics of Some Western Canadian Coals... 

McLaughlin, J. W., G. Liu, M. F. Jurgensen, and M. R. Gale. 1996. Organic carbon characteristics in a spruce swamp five years after harvesting. Soil Science Society of America Journal 60 1228-1236. 

Knappe, D.R.U., Li, L., Quinlivan, P.A., and Wagner, T.B. (2003). Effects of activated carbon characteristics on organic contaminant removal. American Water Works Association Research Foundation Research Report No. 90926. 

It seems clear that a large surface area formed by accessible pores is important for obtaining highly dispersed and active catalysts. However, there are other carbon characteristics that have to be taken into account to explain the catalytic behavior of carbon-supported catalysts. One of the most important is the chemical composition of its surface. 

During our earlier work, it was recognized that adsorption capacity of carbons was dependent on the type of activated carbon used. In order to understand the influence of the chemical and physical characteristics of carbons on NO adsorption and to possibly optimize a process for the selective removal of NO, from combustion flue gas, it was considered important to understand the relationship between adsorption capacity and carbon characteristics, especially the nature of the active binding sites, lliis work used thermogravimetiy/ mass spectrometry (TG/MS) to determine adsorptive capacity of commercially available activated carbons produced firom co, coconut, and petroleum pitch. The relationship between their chemical and physical characteristics relative to NO, adsorptive capacities was explored. 

Various parameters have been identified that influence carbon corrosion, including humidity, with higher humidity enhancing corrosion [94], reactant partial pressure, fuel starvation, and also the carbon characteristics, including surface area and degree of graphitization [94]. As expected, both potential and variations in potential have also a strong influence on carbon corrosion [95]. 

Costa, E. Calleja, G., and Domingo, F., Adsorption of gaseous hydrocarbons on activated carbon Characteristic kineticcurve.AlChEJ., 31(6), 982-991 (1985). 

As shown in Table 4.1, the graphite precursors can be divided into two major classes (a) aromatic hydrocarbons emd flj) polymers, each with different carbonization characteristics. 

Molding. The precursor polymer is often combined with other materials such as solvents to obtain the desired molding and carbonization characteristics. Some of these compositions and processes are considered proprietary by the manufacturers. 

Gilson et al. [12] studied technique to simultaneously reduce both the hydrogen sulfide and siloxanes concentration to less than 1 ppm. Five different commercial activated carbons (AC) previously studied [77] and effective in H2S removal have been tested at L2 at concentration of 100-200 ppm. Samples differ in specific surface area. Their performances are compared to understand which mechanism controls siloxane removal and which carbon characteristic plays a role in the adsorption process. Table 7.5 summarizes data of the tested ACs. 

The catalytic oxidation of hydrocarbons on monolithic catalysts for a short time proceeds efficiently in small-sized simple-design reactors, without formation of solid carbon. Characteristic features of these processes are large time ( 10 K/s) and space ( 10 K/cm) gradients of temperature. These autothennal processes occur in nearly adiabatic conditions, since exothermic reactions rapidly heat the catalyst and gas to about 1000 °C, whereas the heat release rate is too high to allow the gas mixture to be effectively cooled through the walls. 

Table 4. Chemical shifts of Cl, C4 and C6 carbons characteristic of cellulose...

Analysing tne carbon characteristics from tne micropore zone model (Table ) one may note the widening of the slits and enlargement of the crystallites when... 

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