Oxidized asphalt

A variety of other substances can provide the same reaction sulfur yields hydrogen sulfide chlorine yields hydrogen chloride. In some cases, some of the bonds created are quite weak resulting ia, after an iaduction period, a phenomenon termed "fallback." When fallback occurs, usually at a time when the hardened or oxidized asphalt is stored at or near the original processing or reaction temperature, softening of the asphalt is the result (28—31). 

Asphalt Manufacture Saleable asphalts are produced from the residua of selected crudes. The residuum itself may be sold as straight reduced cuts to make it easier to handle, producing the so called cut-back asphalts. Another variation is air blown or oxidized asphalts for improved tenacity, greater resistance to weathering, and decreased brittleness. Emulsified asphalts are made for application at relatively low temperatures. 

A recent processing development has been the continuous oxidizer, shown in Figure 3 (91). The charge is fed to the bottom of the column, where air is also introduced. At the top of the column the liquid overflows into a buffer tank. From this the oxidized asphalt is drawn off by means of a pump, provision being made for recirculation. 

The primer, defined in the first part of this paper as a cut-back of the same or a compatible, unfilled, oxidized asphalt dissolved in a high flash petroleum fraction, should be scrubbed into the concrete surface with a broom or stiff brush (roller or spray application is not recommended) and allowed to dry to permit the solvent to evaporate. This usually takes about 3 to 4 hours, at which time the odor of the solvent will have become faint. This leaves a black deposit of the asphalt in the pores and on the surface of the concrete. If the black color fades away, or becomes gray, the concrete is porous, and another coat of primer is necessary. Repeat until the surface remains black. 

The flash points for both emulsified and oxidized asphalt are shown in Figure 8 as a function of percent sludge. Values shown are averages of two or three tests, usually reproducible to 40°C. The slight variation in flash point suggests that the composition had little effect and that asphalt burned independently. This was further demonstrated by additional tests with 5, 10, 20, 30, 40, 50, and 60% sodium nitrate filler and... 

In contrast to classical GC, IGC probes the stationary phase, in this case a coal, by determining the retention volume of known compounds. The term inverse chromatography was first applied by Davis and Peterson (2), who utilized IGC to determine of the degree of oxidation of asphalt. In later work, the experiments were extended to include measurements of thermodynamic properties (8). Because of their results with oxidized asphalt, IGC may be a good candidate for investigating coals. 

Oxidized Asphalt Vacuum-Reduced Asphalt Cutback Asphalt... 

The test is used for oxidized asphalt. The test method (ASTM D-1328) is used to measure the amount of stain on paper or other cellulosic materials by asphalt. Variations of the cigarette paper stain procedure include the Barber stain talc stain tests are also used. 

CAS 64742-93-4 EINECS/ELINCS 265-196-4 Synonyms Asphalt, blown Asphalt oxide Blown asphalt Hard hydrocarbon Oxidized asphalt... 

Oxide of chromium. See Chromium oxide (ic) Oxidized asphalt. See Asphalt, oxidized Oxidized beeswax CAS 138724-55-7... 

Comparing the asphaltene structure and the data from Table III, the phenomena of association can be seen. The stack height of the cluster will increase according to concentration increase, and the stack height of oxidized asphalt will be larger than that of the original asphalt. 

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