Modelling of the Thermodynamic Equilibrium Conditions for the Formation of TBAB Semi-Clathrates Formed by gas mixtures of Carbon Dioxide, Nitrogen, Hydrogen, Methane and Carbon Monoxide

Abstract

Semi-clathrates are ice like crystalline substance which are like that of gas hydrates. Like clathrate hydrates, the semi-clathrates can entrap gas molecules in its molecular framework. Since semi-clathrate are formed at much milder conditions when compared with the clathrate hydrate. Thus, in the recent years, there has been much interest in using semi-clathrate in applications such as gas storage and separation. The aim of the present study is to measure the dissociation condition of semi-clathrate formed from Tetra-n-butyl ammonium bromide in the presence of the gas mixtures using a developed thermodynamic model. The developed thermodynamic model the PSRK equation of state is used to describe the vapour phase, the LIFAC activity coefficient model is used to compute the activity coefficient in the liquid phase. The van der Waals and Platteeuw theory is employed to describe the semi-clathrate phase. In this model, the Langmuir constants are calculated using the Kihara potential, whereas most of the previously developed model uses the empirical correlation. The thermodynamic model is used in the present work to predict the dissociation condition of the semi-clathrate formed from Tetra-n-butyl ammonium bromide in the presence of the gas mixtures like carbon dioxide (CO2), carbon monoxide (CO), nitrogen (N2) and hydrogen (H2). A good agreement between the experimental and predicted values were observed using this model. The % ARD (average relative deviation) of the calculated and experimental values were in the range of 3.2% to 7.2%.