Advanced Gibbs Energy Methods for Functional Materials and Processes: ChemSheet 1999-2009

ChemSheet is a thermochemical simulation tool, which combines the flexibility and practicality of spreadsheet operations with rigorous, multi-phase thermodynamic calculations. Customised applications are defined as independent worksheets in Excelr and simulations are run directly from the spreadsheet, taking advantage of its functional aspects and graphical features. A user-friendly dialog is available for model build-up. ChemSheet was invented and published by VTT. It was commercialized in a joint venture with GTT Technologies GmbH of Herzogenrath, Germany. During the last decade, ChemSheet and its sister products have been adopted by both industrial users and active scientists worldwide. Due to the generic modelling principles based on Gibbs free energy minimization, the applications range from high temperature systems to biochemical analysis, including materials chemistry, corrosion, industrial reactor scale-up and process simulation. Practical models and expert systems have been developed e.g. in the chemical industry, pulp and paper, cement and lime manufacturing, metallurgy, steelmaking, power production and environmental technologies. Within ChemSheet, the new Constrained Free Energy method allows immaterial constraints in the conservation matrix of the minimization problem, thereby enabling the association of constraint matrix properties with structural, physical, chemical or energetic attributes. Thus, the scope of free energy calculations can be extended well beyond the conventional studies of global chemical equilibria and phase diagrams. The most notable applications include surface and interfacial energies, electrochemical Donnan equilibria, calculation of paraequilibria and the introduction of mechanistic reaction kinetics to Gibbs'ian multiphase analysis. In biochemistry, the new method can be applied for efficient generation of energy diagrams for industrial production pathways within micro-organisms.