Bitumen is a mixture of organic liquid that are highly viscous, black, sticky, entirely soluble in carbon disulfide, and composed primarily of highly condensed polycyclic aromatic hydrocarbons.
Bitumen can now be made from non-petroleum based renewable resources such as sugar, molasses and rice, corn and potato starches. Bitumen can also be made from waste material by factional distillation of used motor oils,
which is sometimes disposed by burning or dumping into land fills. Non-petroleum based bitumen binders can be made light-colored. Roads made with lighter-colored pitch absorb less heat from solar radiation, and become less hot than darker surfaces, reducing their contribution to the urban heat island effect
Extraction is the procedure used for separating the asphalt from the mineral aggregate in an asphaltic paving mixture. The purpose of extraction is to provide a basic for determining the asphalt content of a mixture and to provide asphalt free aggregates which may be used for gradation analysis and such other tests on the aggregates as may be desired. Where further tests on the extraction asphalt are required, a recovery procedure as describe in ASTM Designation: D 1461 is conducted. A number of different methods and types of apparatus may be used. The centrifuge method with trichloroethylene solvent will be described herein.
Equipment and Materials:
- oven, capable of maintaining a temperature of 110±5
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