Critical temperatures and pressures of some dicarboxylic acid diethyl esters

The critical temperatures and pressures of diethyl esters of dicarboxylic acids C2H5OOC(CH2)n-2COOC2H5 with straight alkyl chains and n = 3, 4, 6 have been measured. These data and the results of the previous measurements have been analyzed and the recommended critical properties of dicarboxylic acid diethyl esters from diethyl ethanoate to diethyl hexanoate have been determined. The experimental critical constants of dicarboxylic acid diethyl esters have also been compared with those calculated using the group-contribution methods of Wilson and Jasperson, Marrero and Gani, and Nannoolal, Rarey, and Ramjugernath. The acentric factors of dicarboxylic acid diethyl esters have been calculated.