Volatile carbon

Oxygen infiltration coupled with (steam volatile) carbon dioxide produces enhanced condensate line corrosion. The corrosion rate of steel in the system is particularly high when both gases are present. 

Carbohydrazide itself is of very low volatility, but it decomposes at relatively low temperatures to produce volatile carbon dioxide and ammonia. In theory, the combined corrosive effects of these two materials should be negated in the condensate system, but in practice, this is not always so and both steel and copper corrosion transport problems may develop, primarily as the result of corrosion-enhancement reactions resulting from oxygen in-leakage. It is presumed, therefore, that (similar to hydrazine) some deliberate after-desuperheating line addition of CHZ is necessary if post-boiler section corrosion is to be avoided. 

Equilibrium moisture content, Moisture, Ash, Volatile Matter, Fixed carbon, Volatile carbon. 

The relations between coal reactivity and several parameters are shown in Figs. 3 to 8. In these figures the reactivity of coal is measured by conversion. In the results, volatile carbon % is selected as a more closely related parameter than the common parameters, such as C%9 H, 0, H/C atomic ratio, volatile matter, etc. 

Volatile carbon % is defined by the equation as follows. Volatile carbon %... 

Figure 6. Relationship between conversion and volatile carbon percent in coal (+), with catalyst (O), no catalyst (A), Morwell brown coal...

As stated before, volatile carbon % is considered to be one of the most important parameters of hydroliquefaction. Also a fairly good linear relationship between the volatile carbon % in coal and low temperature tar yield from coal is found in Morwell brown coals, based on the data from the State Electricity Commission of Victoria (SECV) in Australia, as shown in Fig.9 Therefore, the low temperature tar yield is also estimated to be an important parameter. In addition, the color tone of brown coal (lithotypes) is shown in this figure. From this figure, it is observed that both volatile carbon % and low temperature tar yield are in a fairly good relation to the color tone of brown coal. Thus, as proposed by the Australian researchers, the color tone of brown coal is considered to be an important parameter. 

Figure 9. Relationship between low-temperature tar yield and volatile carbon content (O), Australian researcher s data ( + ), present study data.

Allied to flammability is smoke density suppression especially in confined spaces, e.g., airliners, houses, warehouses. Many aromatic compounds bum with a smoky flame (e.g., styrene), whereas corresponding aliphatic compounds tend to burn with a clean "transparent" flame. This is because air-bome poly-aromatic vapours decompose to give volatile carbon (smoke) in low oxygen environments. 

The formation of several volatile carbon hydrides in the hydrogen-graphite reaction between 360 and 800° was reported by Breisacher and Marx (138). The formation of ethane, ethylene, propylene, and even butane suggests that the edge of the carbon layers became hydrogenated in the first step of this reaction. The results were discussed on the basis of a mechanism proposal by Zielke and Gorin (139). 

Data on urban soil from the Portland Aerosol Study (21) were used to obtain an order of magnitude comparison of source ratios to the coefficients of MN(C) in the models. If volatile carbon (21) is assumed to be approximately equal to extractable organic matter (this study) and using a 1 1 ratio for coarse to fine particle mass in New York City (based on our unpublished data), then a ratio of extractable organic matter to MN(C) of 118 can be estimated for urban soil. The coefficients for MN(C) in the models were 46 11 [equation (16)] and 70 26 [equation (19)] for CYC and ACE, respectively. This is quite reasonable agreement in view of the approximations made to obtain a ratio for the soil source. 

The carbon in coal can exist in two forms, volatile carbon and base carbon. Volatile carbon is released by pyrolysis while base carbon remains as a residual char or coke. Both forms of carbon in coal have been utilized in the development of synthetic fuel. 

The acidity of wine is due to organic acids, some of which are fixed— tartaric, malic, succinic—whilst others, such as acetic and also formic, butyric and propionic, which are found in minimal proportions, are volatile carbonic acid plays no part in the acidity of wine. 

The crucibles and covers must be properly shaped to ensure a proper fit. A loose-fitting cover allows air to come in contact with the hot coal sample, with subsequent formation of volatile carbon oxides. Such an occurrence would result in a volatile matter value that is too high. Oxidation is not a serious problem in volatile matter determinations, since the rapid release of large amounts of gases during the test does prevent the entry of air into the crucible, thereby reducing... 

The radioactivity added to the ponds was only accounted for successfully during the first 5 days post-treatment despite knowledge of the size of the major compartments and the use of direct assays such as combustion to 14C02- Loss of radioactivity due to penetration to lower depths in sediment and degradation of the ring label to volatile carbon fragments and 14C02 in the water column may have occurred but are unlikely to total all of the 70 to 80% unaccounted for. The ultimate fate of the radiolabelled material in aquatic systems under field conditions is in need of further study. 

Acetylene (ethyne) C2H2 Gas containing C to C triple bond. Unsaturated chemical compound which can volatilize carbon in radiocarbon dating. 

A colourless, mobile, slowly volatile liquid. It absorbs carbon dioxide from the air forming a volatile carbonate. B.p. 200° to 203°. 

The reaction gases used must contain relatively low concentrations of volatile carbon compounds (typically about 1-2% by volume) with a high excess of hydrogen. 

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