Determination of chemical exergy for compounds of biotechnological interest using different estimation methodologies

Abstract

Different methods of chemical exergy estimation for several organic compounds have been proposed in literature, mainly for those related to the petrochemical and energy industry. However, there is a lack of specific models for the estimation of different biomolecules chemical exergy. The present work aimed to evaluate the performance of two specific chemical exergy estimation methodologies for 42 compounds of biotechnological interest. The methodologies employed were the group contribution method (GC) and semi-empirical correlation. In addition, a methodology for the specific chemical exergy calculation of protein based on empirical information on the amino acid content was proposed. According to the results obtained by the methodologies studied, it was observed that the predicted chemical exergy values of the biomolecules considered were similar to the literature data, presenting an adjustment of R 2 > 0.98. The property estimation GC-based method provided better statistical performance, with average absolute error and average relative error of 0.56 MJ kg −1 and 4.21%, respectively.