keywords: Critical properties, dicarboxylic acids, dimethyl esters, group contribution
Critical temperature (Tc), critical pressure (Pc) and critical volume (Vc) of the linear aliphatic dimethyl esters of dicarboxylic acids CH3-CO2-(CH2)n-CO2-CH3 (with n = 0 to 8) were estimated using Group Contribution Methods. Experimental data on the critical properties were compared with the estimations by group contributory methods of Lydersen, Constantinou and Gani, and Marrero and Gani. In the case of Tc, predictions by the three methods showed average relative deviations (ARD) of 12.16, 19.85 and 13.35%, respectively. Pc estimations by the methods recorded deviations (ARD) of 2.72, 13.37 and 2.14%, respectively. Experimental data for Vc were not available for comparison. The need to expand the databank of critical properties of organic compounds that are vital in the design of process plants, underscores the essence of this study.
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