Solubility of Helium, Nitrogen, Carbon Dioxide and Methane in Water Based on Scaled Particle Theory

Accurate knowledge on the phase equilibrium of gases in liquid is needed to design and operate gas, petroleum and petrochemical plants.In this work, solubility of He, N2, CO2 and CH4 in water based on modified Scaled Particle Theory (SPT) has been studied. SPT is an equilibrium theory of rigid sphere fluids which can be used to model and predict the Henry’s law constant. According to this theory dissolution of gas in liquid takes place through two steps. First, a cavity is created in among solvent molecules and then relocated gas molecule interacts with solvent molecules.The aim of this research is to modify the SPT. Calculations of Henry’s law constant via SPT are related to inherent physical properties and parameters of solvent and solute, that all these parameter are temperature dependent. With considering the temperature dependence of these parameters, more accurate results can be obtained. In this work, temperature dependence of hard sphere diameter of solvent and polarizability of solute have been considered. These parameters have been studied separately by researchers. The basic goal of our work is to study the temperature dependence of these parameters simultaneously and see how it affects the results of SPT. By considering aforementioned modification for different systems, Average Relative Deviation (ARD) is less than 3%.

کلیدواژه ها:

Solubility ، Scaled Particle Theory ، Henry’s law constant ، Water