Asphaltene reaction via supercritical fluid extraction

Conference · Fri Jan 01 04:00:00 EST 1993

OSTI ID:6680035

Deo, M D; Hanson, F V

Supercritical fluid extraction (SFE) of bitumen was carried out in a continuous extractor using propane as the solvent at several temperatures and pressures. The asphaltene contents of the residual fractions in the extractor were compared to the asphaltene content of the original bitumen. Asphaltenes were defined as pentane insolubles in this study. It was found that the absolute asphaltene content of the residual fractions exceeded the asphaltene content of the original bitumen. Even when the asphaltene content was prorated by the weight percent of the residual material, it was found to be higher than the original asphaltene content. The data established that the types of compounds separating as asphaltenes changed as the nature of the mixture was altered by SFE. The data also indicated that it may be inappropriate to perform asphaltene material balances to assess the amount of precipitate. The original asphaltene content of a bitumen that is undergoing compositional changes in a sequence of operations may not be an accurate measure of the precipitating tendency of the bitumen in production and processing operations. The asphaltene content of the residual material varied depending on the extraction conditions and was as much as 3--5 times the original asphaltene content. The asphaltene content of the residual material was a maximum at the most efficient extraction condition which was in the vicinity of the critical temperature of propane. The H/C atomic ratio of the residual fractions was lower compared to the original bitumen, indicating that the ratio of polar to nonpolar compounds may also be important from precipitation considerations. Saturate and aromatic compounds were preferentially extracted and the ratio of asphaltenes to resins increased in the residual fractions relative to the original bitumen.

• Research Organization: Utah Univ., Salt Lake City, UT (United States). Dept. of Chemical and Fuels Engineering
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FC21-89MC26268
• OSTI ID: 6680035
• Report Number(s): DOE/MC/26268-93/C0176; CONF-921142--2; ON: DE93008867
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400 -- Petroleum-- Processing
04 OIL SHALES AND TAR SANDS
040403* -- Oil Shales & Tar Sands-- Refining
ALKANES
ASPHALTENES
ASPHALTS
BITUMENS
DATA
EXPERIMENTAL DATA
EXTRACTION
HYDROCARBONS
INFORMATION
MEDIUM PRESSURE
NUMERICAL DATA
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PRESSURE DEPENDENCE
PROPANE
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENT PROPERTIES
SUPERCRITICAL GAS EXTRACTION
TAR
TEMPERATURE RANGE
TEMPERATURE RANGE 0273-0400 K