New Group Contribution Method for Predicting the Critical Pressures of Fatty Acids and Triglycerides

Abstract

A new and useful method for evaluating and predicting the critical pressures ( c P ) of n-fatty acids and triglycerides was developed in this study. Logarithmic equations which required critical temperature (Tc) and normal boiling temperature (Tb) were proposed for the fatty acids and their corresponding triglycerides. The method predicted with good accuracy the critical pressures ( c P ) of the n-fatty acids, even without the input of the compressibility factor (∆Zb). The deviations of predicted critical pressures from experimental values were between (0-7)%, except for Caproic and Caprylic acids; where the method under predicted the critical pressures with deviations of -6.64% and -11.31% respectively. Experimental Pc values for the triglycerides were not available in the open literature for comparison.