Identification of the phase of a substance from the derivatives of pressure, volume and temperature, without prior knowledge of saturation properties: Extension to solid phase

Una extensión teórica aplicada a los ácidos puros de cadena larga en la fase líquida para analizar su comportamiento en la fase sólida

“…Calculated results were evaluated regarding the conformation of molecule studied but not compared with the experimental values due to they do not exist. It is observed that, Murnaghan formulation [8][9][10], gives almost the same results as reported by input parameters, the values of bulk modulus and its first-order pressure derivative for the acids stearic, palmitic and lauric, which were taken from extending results from P-R equation [7], at low and constant temperature. The values of bulk modulus and its first-order pressure derivative for acids with long carbon chain was taken to be in the range of 2.2 <K T <3.3 GPa and 18< K T '<61.…”

“…Equation ( 4), has been applied to the solid systems such as NaCl and MgO at relatively low pressure, the calculated values of the isothermal bulk modulus was found agree with available experimental data in the pressure range. Jayanti and Venkatarathnam 2016 [8], have shown the variation of isothermal compressibility (k T ) of solid carbon dioxide with the temperature at specified pressures, along with that of the vapour and liquid phases. The calculations with the vapour phase are limited to the sublimation region, and those with the liquid phase to the solid melting region.…”

“…Poling et al [7], used the following criteria based on the isothermal compressibility (k) to identify the phase of a fluid. The method works only at low pressures and away from the critical point where the isothermal compressibility of the vapour and liquid phases in equilibrium are very different [8].…”

“…In the present work, we have studied the mechanical propierties, especially volume compression (V/ V 0 ) of three acids with a long carbon chain by extending the bulk modulus property in liquid phase to the solid phase. Then, it was feasible to widely used Tait, Vinet, Murnaghan and Kholyia Equation of State (EOS) [8][9][10][11][12][13]. Calculated results were evaluated regarding the conformation of molecule studied but not compared with the experimental values due to they do not exist.…”

Comparison of Phase Identification Methods Used in Oil Industry Flow Simulations

“…Venkatarathnam and Oellrich therefore recommend checking whether the point (∂ k ∂ T ) P = 0 occurs at a temperature below the actual temperature. The temperature derivative of the isothermal compressibility has been recently used to identify solid phases …”