文摘
The solubility of levulinic acid in supercritical carbon dioxide in the absence and presence of ethanol (mole fraction of ethanol x3 = 0.0, 0.027, and 0.051) as a cosolvent was measured with a synthetic method at temperatures from (313.0 to 342.4) K and pressures from (8.0 to 19.0) MPa. It is demonstrated that, at a fixed temperature, the solubility of levulinic acid increases with increasing pressure; at a fixed pressure, it decreases with increasing temperature. When ethanol is added into supercritical carbon dioxide as a cosolvent, the solubility of levulinic acid increases greatly, and it increases with the concentration of the added ethanol. The experimental solubility data can be correlated using the Chrastil model and a modified Chrastil model with four adjustable parameters.