Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (08): 1803-1808.doi: 10.3866/PKU.WHXB201205211


Gas-Liquid Phase Boundary Lines and Critical Curve for the Water+Methane System

TIAN Yu-Qin1,2, TIAN Yi-Ling, ZHAO Lin1, ZHU Rong-Jiao, MA Chao1   

  1. 1. College of Petroleum Engineering, Yangtze University, Jingzhou 434023, Hubei Province, P. R. China; 1§Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China;
    2. Institute of Production Technology, Shengli Oilfield Company, China Petroleum & Chemical Corporation, Dongying 257000, Shandong Province, P. R. China
  • Received:2012-03-07 Revised:2012-05-21 Published:2012-07-10
  • Contact: ZHU Rong-Jiao


The isothermal gas-liquid phase boundary lines and critical curve were determined for the water+methane system. Experiments were performed in a high-pressure volume-variable autoclave with a sapphire window and magnetic stirring. The temperature range was from 433.0 to 633.0 K and pressure from 30.00 to 300.00 MPa. Henry coefficients of dilute methane solutions were determined; the results show that these coefficients decrease with increasing temperature in the range from 433.0 to 603.0 K. The equilibrium gas-liquid ratios, partial molar solution enthalpy, and partial molar solution entropy were also calculated. The results show that the difference in the cohesive energy density between methane and water is very large.

Key words: Water+methane system, Phase boundary line, Critical curve, Henry’s coefficient, Partial molar solution enthalpy, Partial molar solution entropy