In recent years, the most commonly used method is the way l W. Cole Bert will be a separation of asphalt into saturates, aromatics, colloid and asphaltene fractions. There is a certain regularity between the content of the components in the asphalt and the asphalt and technical properties, as shown in the figure.
According to explain the colloid structure, with the dispersion medium saturation and aromatics content reduced, protective substances and the dispersed phase of asphaltene content increased, asphalt by sol structure into sol gel structure even gel structure. The technical indexes of asphalt penetration decreases, the softening point increased. And when the proportion of the proportion of the asphalt in the coordination, can get the best delay. But the law is obtained from the same source of oil and the same process of asphalt as table in asphalt for Daqing crude oil, the acrylic removal process for asphalt for the same oil, using different process, or of different crude oil of the same process and different crude oil and process obtained asphalt, they even with similar groups of asphalt content but their technical properties can vary greatly. The cause of these phenomena is due to the different oil source and process of asphalt, their chemical group points, although can be very close, but chemical structure of each component is not the same, solubility parameters of each component of the different. That is, the phase solubility of each component is different, so the formation of different colloid structure, so their technical properties are not the same.
Asphalt belongs to the hydrophobic material, it impermeable, almost insoluble in water, acetone, diethyl ether and diluted ethanol, soluble in carbon disulfide, carbon tetrachloride, sodium hydroxide
Asphalt and its flue gas can stimulate the skin and mucous membranes, with the light toxic and carcinogenic effects. Three kinds of asphalt in China coal tar asphalt shale toxicity: > > petroleum asphalt, before the two carcinogenic. The main skin damage of asphalt: phototoxic dermatitis lesions limited to face, neck and other exposed parts; melanotic lesions often symmetrical distribution in the exposed parts, flaky, a brown - dark brown, brown black; occupational acne; verrucous vegetations and accident caused by thermal burns. In addition, there are still dizziness, headache, headache, chest tightness, fatigue, nausea, loss of appetite and so on systemic symptoms and eye, nose, and throat irritation.