1. Thermodynamics Research Unit, School of Chemical Engineering, University of KwaZulu-Natal, Howard College Campus, Durban, South Africa, and MINES ParisTech, CEP/TEP - Centre énergétique et procédés, CNRS FRE 2861, CNRS FRE 2861, 35 Rue Saint Honoré, 77305 Fontainebleau, France