Hukkerikar, Amol1; Meier, Robert J.3; Sin, Gürkan4; Gani, Rafiqul1
1 Department of Chemical and Biochemical Engineering, Technical University of Denmark2 Computer Aided Process Engineering Center, Department of Chemical and Biochemical Engineering, Technical University of Denmark3 DSM Chemtech Center4 Centre for oil and gas – DTU, Center, Technical University of Denmark
A model that yields chemical accuracy for a broad range of organic molecules is presented. The range of applicability of such an accurate model is very broad: it can be used by chemists to predict equilibria while fostering new chemistries and allow process engineers to make more reliable designs. The model which is group-contribution (GC) based, estimates gas phase standard enthalpy of formations (ΔfH°gas) of organic compounds. To achieve the chemical accuracy, a systematic property-data-model analysis, which allows efficient use of knowledge of the experimental data of ΔfH°gas and the molecular structural information is employed. Based on the findings of property-data-model analysis, new structural parameters are defined and included in the GC-model to provide additional structural information for compounds having large correlation errors and to thereby improve accuracy of ΔfH°gas predictions through better correlation of data. For parameter estimation, a data-set containing 861 experimentally measured values of a wide variety of organic compounds (hydrocarbons, oxygenated compounds, nitrogenated compounds, multi-functional compounds, etc.) is used. The developed property model for ΔfH°gas is fully predictive and is based exclusively on the molecular structure of the organic compound. Compared to other currently used property prediction methods, the developed GC-model for ΔfH°gas provides significant improvement in accuracy with an average absolute error of 1.75kJ/mol and standard deviation of 2.61kJ/mol.
Fluid Phase Equilibria, 2013, Vol 348, p. 23-32
Enthalpy of formation; Group-contribution method; Quantum mechanical method; Chemical accuracy; Benson method