Study of the solubility of antracene in pure and modified supercritical carbon dioxide

Abstract In the framework of the supercritical fluid extraction regeneration of catalysts, an original experimental device was created for measuring the solubility of substances in pure and modified supercritical carbon dioxide, protected by a RF patent for a useful model. To prevent entrainment during the implementation of the process of extraction of substances in the solid state, a special vessel with a microporous membrane was used in the extraction cell. The solubility of anthracene in pure supercritical carbon dioxide was studied with 423, 435, 448 K isotherms in the pressure range from 9.6 to 22 MPa. It is established that an increase in temperature and pressure contribute to an increase in the solubility of anthracene. In order to increase the dissolving ability of SC-CO2, a search for modifiers of various nature (acetone, hexane, ethanol) was conducted. It is revealed that hexane and ethanol are more effective modifiers. In this regard, the effect of the concentration of these modifiers on the dissolving ability was investigated. The content in the solvent 2% of the mass. hexane and ethanol have a maximum effect than their other concentration. The solubility of anthracene in SC-CO2 modified with hexane and ethanol was studied at a 435 K isotherm in the pressure range 10-20 MPa. The use of modifiers made it possible to increase the solubility of anthracene using ethanol and hexanan by 56% and 76%, respectively. The solubility of anthracene in pure supercritical carbon dioxide is described using the Peng-Robinson equation of state and three adjustable parameters. To describe the solubility of anthracene in a modified SC-CO2, only one adjustable parameter was used. In addition, the descriptions of the solubility of anthracene in pure SC-CO2 obtained experimentally in this work and in the works of other authors are presented. The obtained dependences of the parameters of the binary interaction on temperature make it possible to interpolate the values of solubility on the basis of existing experimental data.