CO2 has recently received a lot of attention as the main contributor to the warming of the Earth’s atmosphere. Thus, sickness the question of acid gas removal has become increasingly significant in the treatment of natural gas, physician synthetic gas, ammonia production, Claus feed gases and landfill gases. Both aqueous solutions of physical organic solvents and chemical solvents have been used in acid gas removal. Solubility measurements are essential to the design of the absorption process but also to the measurement of the kinetic rates. The main objective of the present study is to screen a large number of physical solvents from a specific chemical family for their capacity in carbon dioxide removal. The best solvent should have a the highest capacity for acid gases, lowest capacity for hydrocarbons, low volatility, moderate viscosity, high boiling point, excellent thermal and chemical stability. Corrosion rates and foaming should be low.
A glass reactor manufactured by Autoclave (Pennsylvania, USA) is used for these solubility studies. The apparatus can be operated up to a pressure of 150 psi and a temperature of 350 °F. Gases of interest are carbon dioxide, methane, ethane, nitrous oxide, hydrogen sulfide and sulfur dioxide. The solvents screened in this study are mainly polyethylene glycol ethers and mixtures of these solvents. The results will be compared to mixtures of other physical solvents recently made available to the industry. The data obtained for pure and aqueous mixtures will be used to test new semi-empirical models for solubility prediction.