Physico-Chemical and Structural Characterization of Carbons

Coke combustion and gasification kinetics in ethane steam crackers

“…The XRD study of the coke reveals that the tube metal side coke has a more crystalline structure and is more graphitized than the process gas side coke. This is attributed to the graphitizing process as described by Marchand 20. The XRD results correspond with those of Bennet and Price,15 Jackson et al,21 and Marchand 20…”

Treating contaminated soil by conversion into carbonaceous adsorbents: an investigation of activation procedures

“…There was a slight increase in the rate of weight loss at approximately 700 °C, one possible cause of which has been considered by Snoeyink and Weber,26 who report that as the temperature of preparation for carbon increases above 700 °C, the mechanical strength and electrical conductivity of the material increases. This same phenomenon has been related to the graphitisation reactions which are known to occur in carbons which exhibit mesophase properties and which were discussed by Marchand 27. Thus, the observed weight loss could have been due to the further elimination of hydrogen and light hydrocarbons as graphitisation reactions proceeded.…”

Steam Cracking Coke Properties and Their Influence on Furnace Run Length Predictions: Experimental and Modeling Study

“…XRD is used to characterize two different coke flakes of sample E2. The low height of the (100) and (101) peaks indicates that only a small amount of graphite crystals can be found. , The spectra from both flakes are very similar to one another. The lattice constant d can be calculated as 3.420 and 3.438 Å for flake 1 and 2, respectively.…”

“…“Graphitization path” of carbons as monitored through the E2G and 2700 cm –1 line widths. Adapted from ref with the addition of steam cracking coke experiments: ▽. Reprinted with permission from ref Copyright (1986) Springer.…”

“…Raman spectroscopy is one of the few techniques that can be sensitive for a diversity of structures present in coke samples at a spatial resolution of 1–2 μm , with a penetration of ∼0.1 to 0.2 μm from the surface . Using Raman data, the following parameters can be used to create a “graphitization path”: Parameters indicating two-dimensional ordering (i.e., showing the progressive building of “graphene”) The frequency of the E 2G line, ν E2G , which shifts from 1600 to 1580 cm –1 . The E 2G line width, Δν E 2G , which decreases to 20 cm –1 . Parameters indicating the onset of the three-dimensional order: The 2700 cm –1 line width, Δν 2700 : it decreases down to a minimum during the two-dimensional ordering and then increases with complete graphitization. …”