A systematic experimental study on the phase behavior of complex fluid mixtures up to near-critical region

The near-critical phase behavior of five synthetic reservoir fluid mixtures has been systematically studied using a ROP (France) high-pressure PVT sys tem. The C-7(+)-content in the prepared samples ranges from 6.67 to 11.15 m ol%. Through a series of constant composition expansion experiments perform ed in the temperature range of 303-433 K, the compressibility factor of com pressed fluid (in the single-phase region), partial pressure-temperature (P -T) phase envelope, total molar volume and liquid volume fraction in the tw o-phase region have been measured for each sample. In addition, the critica l point data of three samples were determined. (C) 2001 Elsevier Science B. V. All rights reserved.