Solubilities of lactic acid and 2-hydroxyhexanoic acid in supercritical CO2

Solubilities of lactic acid and 2-hydroxyhexanoic acid in supercritical CO2 have been measured at T = (311 or 313, 318, 328 K) in the pressure range f rom 50 to 200 bar. The measurements have been performed using a flow-type a pparatus. The solute solubility in compressed carbon dioxide increased with pressure at all investigated temperatures. At pressures below 130 bar, a s olubility decrease on temperature increase was observed. An accurate correl ation method for the solubility of low volatile substances in supercritical CO2 has been applied for the interpolation of the experimental results. (C ) 1999 Elsevier Science B.V. All rights reserved.