Asphaltenes Help Make Asphalt

Asphalt Chemistry:

Asphalt is a complex mixture of hydrocarbons which can be separated into two major fractions - asphaltenes and maltenes (petrolenes)

Separating of asphaltenes and maltenes fractions is done by diluting asphalt with straight chain, saturated hydrocarbons (n-alkanes) such as: Pentane (C₅H₁₂)

and Heptane (C₇H₁₆) (below)

Asphaltenes are the portion of asphalt which precipitates out when treated as above. It is then a dark brown to black solid with a molecular weight of 1800 - 3000.  One attempt to derive its chemical formula (based on Athabasca bitumen) was C₂₀₀H₂₄₆N₂S₇O₄.   The maltenes remain in solution in the n-alkane solvent.

Asphalt Products from the Lloydminster Refinery

•     Paving Asphalts
•     Road Oils
•     Polymer Modified Asphalts (PMA)
•     Roofing Asphalts

Asphalt Specifications

Two principal specifications are available to the paving industry:

1.     Canadian General Standards Board (CGSB) "Asphalt Cements for Paving   Purposes", CAN/SGSB - 16.3 - M.90
           - Penetration - Viscosity Graded Asphalts
           - Temperature Susceptibility
2.     Strategic Highway Research Program (SHRP)
           - Performance Graded Asphalt
           - Six newly developed tests to grade asphalt by performance rather than by physical tests.