Georgios M. Kontogeorgis

Bio: Georgios M. Kontogeorgis is an academic researcher from Technical University of Denmark. The author has contributed to research in topics: Equation of state & UNIFAC. The author has an hindex of 54, co-authored 367 publications receiving 11069 citations. Previous affiliations of Georgios M. Kontogeorgis include HTW Berlin - University of Applied Sciences & National Technical University of Athens.

An Equation of State for Associating Fluids

Abstract: An equation of state (EoS) suitable for describing associating fluids is presented. The equation combines the simplicity of a cubic equation of state (the Soave−Redlich−Kwong), which is used for the physical part and the theoretical background of the perturbation theory employed for the chemical (or association) part. The resulting EoS (Cubic Plus Association) is not cubic with respect to volume and contains five pure compound parameters which are determined using vapor pressures and saturated liquid densities. Excellent correlations of both vapor pressures and saturated liquid volumes are obtained for primary-alcohols (from methanol up to 1-tridecanol), phenol, tert-butyl alcohol, triethylene glycol, and water. Moreover, excellent prediction of saturated liquid volumes may be obtained from parameters which have been estimated by regressing only vapor pressures. Finally, we suggest a method for reducing the number of adjustable parameters for alcohols to three while maintaining the good correlation of vap...

Thermodynamic Models for Industrial Applications: From Classical and Advanced Mixing Rules to Association Theories

Abstract: Preface. About the Authors. Acknowledgments. List of Abbreviations. List of Symbols. PART A INTRODUCTION. 1 Thermodynamics for Process and Product Design. Appendix. References. 2 Intermolecular Forces and Thermodynamic Models. 2.1 General. 2.2 Coulombic and van der Waals forces. 2.3 Quasi-chemical forces with emphasis on hydrogen bonding. 2.4 Some applications of intermolecular forces in model development. 2.5 Concluding remarks. References. PART B THE CLASSICAL MODELS. 3 Cubic equations of state: the classical mixing rules. 3.1 General. 3.2 On the parameter estimation. 3.3 Analysis of the advantages and shortcomings of cubic EoS. 3.4 Some recent developments with cubic EoS. 3.5 Concluding remarks. Appendix. References. 4 Activity coefficient models Part 1: random-mixing based models 4.1 Introduction to the random-mixing models. 4.2 Experimental activity coefficients. 4.3 The Margules equation. 4.4 From the van der Waals and van Laar equation to the regular solution theory. 4.5 Applications of the Regular Solution Theory. 4.6 SLE with emphasis on wax formation. 4.7 Asphaltene precipitation. 4.8 Concluding remarks about the random-mixing-based models. Appendix. References. 5 Activity coefficient models Part 2: local composition models, from Wilson and NRTL to UNIQUAC and UNIFAC. 5.1 General. 5.2 Overview of the local composition models. 5.3 The theoretical limitations. 5.4 Range of applicability of the LC models. 5.5 On the theoretical significance of the interaction parameters. 5.6 LC models: some unifying concepts. 5.7 The group contribution principle and UNIFAC. 5.8 Local-composition-free volume models for polymers. 5.9 Conclusions: is UNIQUAC the best local composition model available today? Appendix. References. 6 The EoS/ GE mixing rules for cubic equations of state. 6.1 General. 6.2 The infinite pressure limit (the Huron-Vidal mixing rule). 6.3 The zero-reference pressure limit (The Michelsen approach). 6.4 Successes and limitations of zero reference pressure models. 6.5 The Wong Sandler (WS) mixing rule. 6.6 EoS/ GE approaches suitable for asymmetric mixtures. 6.7 Applications of the LCVM, MHV2, PSRK and WS mixing rules. 6.8 Cubic EoS for polymers. 6.9 Conclusions: achievements and limitations of the EoS/ GE models. 6.10 Recommended models so far. Appendix. References. PART C ADVANCED MODELS AND THEIR APPLICATIONS. 7 Association theories and models: the role of spectroscopy. 7.1 Introduction. 7.2 Three different association theories. 7.3 The chemical and perturbation theories. 7.4 Spectroscopy and association theories. 7.5 Concluding remarks. Appendix. References. 8 The Statistical Associating Fluid Theory (SAFT). 8.1 The SAFT EoS: a brief look at the history and major developments. 8.2 The SAFT equations. 8.3 Parameterization of SAFT. 8.4 Applications of SAFT to non-polar molecules. 8.5 GC SAFT approaches. 8.6 Concluding remarks. Appendix. References. 9 The Cubic-Plus-Association equation of state. 9.1 Introduction. 9.2 The CPA EoS. 9.3 Parameter estimation: pure compounds. 9.4 The First applications. 9.5 Conclusions. Appendix. References. 10 Applications of CPA to the oil and gas industry. 10.1 General. 10.2 Glycol water hydrocarbon phase equilibria. 10.3 Gas hydrates. 10.4 Gas phase water content calculations. 10.5 Mixtures with acid gases (CO2 and H2S). 10.6 Reservoir fluids. 10.7 Conclusions. References. 11 Applications of CPA to chemical industries. 11.1 Introduction. 11.2 Aqueous mixtures with heavy alcohols. 11.3 Amines and ketones. 11.4 Mixtures with organic acids. 11.5 Mixtures with ethers and esters. 11.6 Multifunctional chemicals: glycolethers and alkanolamines. 11.7 Complex aqueous mixtures. 11.8 Concluding remarks. Appendix. References. 12 Extension of CPA and SAFT to new systems: worked examples and guidelines. 12.1 Introduction. 12.2 The case of sulfolane: CPA application. 12.3 Application of sPC SAFT to sulfolane-related systems. 12.4 Applicability of association theories and cubic EoS with advanced mixing rules (EoS/GEmodels) to polar chemicals. 12.5 Phenols. 12.6 Conclusions. References. 13 Applications of SAFT to polar and associating mixtures. 13.1 Introduction. 13.2 Water-hydrocarbons. 13.3 Alcohols, amines and alkanolamines. 13.4 Glycols. 13.5 Organic Acids. 13.6 Polar non-associating compounds. 13.7 Flow assurance (asphaltenes and gas hydrate inhibitors). 13.8 Concluding Remarks. References. 14 Applications of SAFT to polymers. 14.1 Overview. 14.2 Estimation of parameters for polymers for SAFT-type EoS. 14.3 Low-pressure phase equilibria (VLE and LLE) using simplified PC SAFT. 14.4 High-pressure phase equilibria. 14.5 Co-polymers. 14.6 Concluding remarks. Appendix. References. PART D THERMODYNAMICS AND OTHER DISCIPLINES. 15 Models for electrolyte systems. 15.1 Introduction: importance of electrolyte systems and modeling challenges. 15.2 Theories of ionic (long-range) interactions. 15.3 Electrolyte models: activity coefficients. 15.4 Electrolyte models: Equation of State. 15.5 Comparison of electrolyte EoS: capabilities and limitations. 15.6 Thermodynamic models for CO2 water alkanolamines. 15.7 Concluding remarks. References. 16 Quantum chemistry in engineering thermodynamics. 16.1 Introduction. 16.2 The COSMO RS method. 16.3 Estimation of association model parameters using QC. 16.4 Estimation of size parameters of SFT-type models from QC. 16.5 Conclusions. References. 17 Environmental thermodynamics. 17.1 Introduction. 17.2 Distribution of chemicals in environmental ecosystems. 17.3 Environmentally friendly solvents: supercritical fluids. 17.4 Conclusions. References. 18 Thermodynamics and colloid and surface chemistry. 18.1 General. 18.2 Intermolecular vs. interparticle forces. 18.3 Interparticle forces in colloids and interfaces. 18.4 Acid base concepts in adhesion studies. 18.5 Surface and interfacial tensions from thermodynamic models. 18.6 Hydrophilicity. 18.7 Micellization and surfactant solutions. 18.8 Adsorption. 18.9 Conclusions. References. 19 Thermodynamics for biotechnology. 19.1 Introduction. 19.2 Models for Pharmaceuticals. 19.3 Models for amino acids and polypeptides. 19.4 Adsorption of proteins and chromatography. 19.5 Semi-productive models for protein systems. 19.6 Concluding Remarks. Appendix. References. 20 Epilogue: thermodynamic challenges in the twenty-first century. 20.1 In brief. 20.2 Petroleum and chemical industries. 20.3 Chemicals including polymers and complex product design. 20.4 Biotechnology including pharmaceuticals. 20.5 How future needs will be addressed. References. Index.

Ten Years with the CPA (Cubic-Plus-Association) Equation of State. Part 1. Pure Compounds and Self-Associating Systems

Abstract: CPA (Cubic-Plus-Association) is an equation of state that is based on a combination of the Soave−Redlich−Kwong (SRK) equation with the association term of the Wertheim theory. The development of CPA started in 1995 as a research project funded by Shell (Amsterdam), and the model was first published in 1996. Since then, it has been successfully applied to a variety of complex phase equilibria, including mixtures containing alcohols, glycols, organic acids, water, and hydrocarbons. Focus has been placed on cases of industrial importance, e.g., systems with gas-hydrate inhibitors (methanol, glycols), glycol regeneration and gas dehydration units, oxygenate additives in gasoline, alcohol separation, etc. This manuscript, which is the first of a series of two papers, offers a review of previous applications and illustrates current focus areas related to the estimation of pure compound parameters, alcohol−hydrocarbon vapor−liquid equilibria (VLE) and solid−liquid equilibria (SLE), as well as aqueous systems. Th...

Multicomponent phase equilibrium calculations for water–methanol–alkane mixtures

Abstract: Prediction of phase equilibrium for multicomponent systems containing associating compounds (e.g., water and alcohols) is essential in a number of engineering applications (e.g., environmental technology, gas hydrate inhibition) and at the same time represents one of the most stringent tests for a thermodynamic model. Conventional models (e.g., cubic equations of state and excess Gibbs free energy models) provide rapid and often reliable estimates of phase equilibrium in many cases but extension to multicomponent systems, especially those containing water is often troublesome. On the other hand, novel association equations of state perform considerably better but are slower compared to conventional models. Furthermore, the extension of several of them to cross-associating systems (e.g., water–alcohols) exhibits problems. In this work, the performance of two well-known conventional models (SRK and NRTL) is compared for multicomponent systems to a recently proposed association equation of state both in terms of accuracy of predictions and timing. The proposed model incorporates the Wertheim chemical association theory (employed previously in models such as SAFT) and the SRK equation. The model is applied in this work to multicomponent systems in such a way that the inclusion of the Wertheim theory does not give execution times much higher than conventional models. The model yields very satisfactory predictions of multicomponent equilibria for aqueous (both vapor–liquid and liquid–liquid equilibria) systems containing methanol, gases and hydrocarbons, which are moreover, as will be demonstrated in this work, considerably better compared to SRK and NRTL.

Carbon capture and storage (CCS): the way forward

Abstract: Carbon capture and storage (CCS) is broadly recognised as having the potential to play a key role in meeting climate change targets, delivering low carbon heat and power, decarbonising industry and, more recently, its ability to facilitate the net removal of CO2 from the atmosphere. However, despite this broad consensus and its technical maturity, CCS has not yet been deployed on a scale commensurate with the ambitions articulated a decade ago. Thus, in this paper we review the current state-of-the-art of CO2 capture, transport, utilisation and storage from a multi-scale perspective, moving from the global to molecular scales. In light of the COP21 commitments to limit warming to less than 2 °C, we extend the remit of this study to include the key negative emissions technologies (NETs) of bioenergy with CCS (BECCS), and direct air capture (DAC). Cognisant of the non-technical barriers to deploying CCS, we reflect on recent experience from the UK's CCS commercialisation programme and consider the commercial and political barriers to the large-scale deployment of CCS. In all areas, we focus on identifying and clearly articulating the key research challenges that could usefully be addressed in the coming decade.

Carbon capture and storage update

Abstract: In recent years, Carbon Capture and Storage (Sequestration) (CCS) has been proposed as a potential method to allow the continued use of fossil-fuelled power stations whilst preventing emissions of CO2 from reaching the atmosphere. Gas, coal (and biomass)-fired power stations can respond to changes in demand more readily than many other sources of electricity production, hence the importance of retaining them as an option in the energy mix. Here, we review the leading CO2 capture technologies, available in the short and long term, and their technological maturity, before discussing CO2 transport and storage. Current pilot plants and demonstrations are highlighted, as is the importance of optimising the CCS system as a whole. Other topics briefly discussed include the viability of both the capture of CO2 from the air and CO2 reutilisation as climate change mitigation strategies. Finally, we discuss the economic and legal aspects of CCS.

Post-Combustion CO2 Capture Using Solid Sorbents: A Review

Abstract: Post-combustion CO2 capture from the flue gas is one of the key technology options to reduce greenhouse gases, because this can be potentially retrofitted to the existing fleet of coal-fired power stations. Adsorption processes using solid sorbents capable of capturing CO2 from flue gas streams have shown many potential advantages, compared to other conventional CO2 capture using aqueous amine solvents. In view of this, in the past few years, several research groups have been involved in the development of new solid sorbents for CO2 capture from flue gas with superior performance and desired economics. A variety of promising sorbents such as activated carbonaceous materials, microporous/mesoporous silica or zeolites, carbonates, and polymeric resins loaded with or without nitrogen functionality for the removal of CO2 from the flue gas streams have been reviewed. Different methods of impregnating functional groups, including grafting techniques and modifying the support materials, have been discussed to en...