Journal of Petroleum Geology, Vol.4, No.2, pp. 195-223, 1981

©Copyright 2000 Scientific Press, Ltd.

AQUEOUS SOLUBILITY OF CRUDE OIL TO 400°C AND 2,000 BARS PRESSURE IN THE PRESENCE OF GAS*

Leigh C. Price**

*This article and the work therein is dedicated to Ron Pingenot. He too could have done the work, but took a different path.

**US Geological Survey, Denver Federal Center, Denver, CO 80225, USA. Editorial Note:
The author’s consideration of a primary petroleum migration mechanism, based on the data presented in this paper. appeared in the JOURNAL OF PETROLEUM GEOLOGY. 4, 1, July 1981, pp. 89-101.

Abstract

This study reports aqueous solubilities of crude oil distillation fractions over the carbon number range C1-C34 as a function of: temperature (100° to 400°C), pressure (100 to 2,000 bars), NaCl concentration, and gas in solution (N2, C02, CH4). Experimental parameters were designed so that conditions within a petroleum basin would be duplicated. Increases in temperature increased crude oil solubility, and the higher molecular weight species were affected more positively than lower molecular weight species. Increases in pressure or salinity decreased solubility. The presence of gas in solution increased the solubility of high molecular weight hydrocarbons (>C24) over all temperatures, and increased the solubility of lower molecular weight hydrocarbons at high temperatures (>180-260°C). Gas decreased the solubility of low molecular weight hydrocarbons at low temperatures.