Structural difference between petroleum and coal-derived asphaltenes

Conference · Sat Sep 01 04:00:00 EDT 1979 · Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States)

OSTI ID:5723357

Yen, T F

A very distinctive feature of coal-derived asphaltenes is that they appear to be associated both in concentrated and diluted solutions, and, particularly, in nonpolar solvents. This fact is supported by the viscosity measurement. The hydrogen-bonding nature of the interaction within the coal-derived asphaltenes is important. The weak linkage in coal and coal-derived products may be due to the excessive inter- and intra-molecular bonding. The fact that the solubilization and swelling curves are similar is important. This type of bonding may increase its extent of crosslink so much that carboid (or preasphaltene) is no longer benzene-soluble. There has been limited work on the long-range order of coal-derived asphaltene. The aromaticity of petroleum-derived asphaltene (f/sub a/ = 0.2 to 0.5) is lower than that of coal-derived asphaltene (f/sub a/ = 0.6 to 0.7). The aromatic ring systems within petroleum-derived asphaltene are much more condensed than that of coal-derived asphaltene. The substituents of the petroleum-derived asphaltenes are longer (n = 4 - 6) than those of coal-derived asphaltenes (n = 1). The aromatic system of petroleum-derived asphaltene is extensively substituted (70 to 80%), whereas the coal-derived asphaltene is sparingly substituted (35 to 45%). The molecular weight of petroleum-derived asphaltene is ca. 10 times higher than that of the coal-derived asphaltene. Petroleum-derived asphaltene is less reactive to physical or chemical agents than that of coal-derived asphaltene. Petroleum-derived asphaltene is more highly associated (Me = 5 - 7) than that of coal-derived asphaltene (Me = 2 - 4). This will be reflected in the ease of processing. Petroleum-derived asphaltene is less polar than the coal-derived asphaltene.

• Research Organization: Univ. of Southern California, Los Angeles
• OSTI ID: 5723357
• Report Number(s): CONF-790917-(Vol.24)(No.4)
• Conference Information: Journal Name: Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States) Journal Volume: 24:4
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010405* -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
010600 -- Coal
Lignite
& Peat-- Properties & Composition
02 PETROLEUM
023000 -- Petroleum-- Properties & Composition
ASPHALTENES
ASPHALTS
BITUMENS
CHEMICAL BONDS
COAL LIQUIDS
COMPARATIVE EVALUATIONS
ENERGY SOURCES
FOSSIL FUELS
FUELS
MOLECULAR WEIGHT
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PETROLEUM
TAR
VISCOSITY