THERMODYNAMIC PROPERTIES OF NONELECTROLYTE SOLUTIONS
CONTENTS PART I: EXTENDED SUMMARY I 1 INTRODUCTION: SCOPE, OBJECTIVES AND THE AUDIENCE OF GUIDELINES MOTIVATION OBJECTIVES AUDIENCE SCOPE I 2 DEFINITIONS I 3 FROM AQUEOUS TO SOLID SOLUTIONS I 4 BASIC THERMODYNAMICS OF SOLID SOLUTIONS THE ENTHALPY OF MIXING THE ENTROPY OF MIXING REGULAR, SUBREGULAR AND GENERALISED MIXING MODELS DILUTE SOLID SOLUTIONS ON THE RELEVANCE OF NON-IDEALITY SOLID SOLUTION VERSUS OTHER UPTAKE MODES CONCEPTS AND APPROXIMATIONS IN GEOCHEMICAL MODELLING OF AQ-SS SYSTEMS I 4 7 1 LIPPMANN DIAGRAMS, A TOOL TO VISUALISE BINARY AQ-SS SYSTEMS KINETIC AND THERMODYNAMIC APPROXIMATIONS TO AQ-SS IN GEOCHEMICAL REACTIVE TRANSPORT MODELLING I 5 EXPERIMENTAL AND ANALYTICAL ASPECTS SYNTHESIS PROCEDURES CHARACTERIZATION OF THE SOLID SOLUTION SOLUBILITY MEASUREMENTS IN AQUEOUS SOLUTIONS PARTITION/DISTRIBUTION EXPERIMENTS DIRECT MEASUREMENTS OF THERMODYNAMIC AND MIXING PROPERTIES OF SOLIDS IN AQ-SS SYSTEMS I 5 5 1 RETRIEVAL OF EXCESS GIBBS ENERGY FROM ELECTROCHEMICAL MEASUREMENTS I 5 5 2 CALORIMETRY I 6 TESTING THE AQ-SS CONCEPTS AND METHODS IN NUCLEAR WASTE MANAGEMENT RELEVANT SYSTEMS RADIUM AND ITS INCORPORATION INTO THE BARITE SOLID SOLUTION FAMILY: ENVIRONMENTAL IMPLICATIONS I 6 1 1 THE RADIUM-BARITE RELATIONSHIP IN NATURAL AND ANTHROPOGENIC ENVIRONMENTS I 6 1 2 NUMERICAL MODELLING INVOLVING (BA,RA)SO4 SOLID SOLUTIONS I 6 1 3 CONCLUSIONS CEMENT PHASES – SOLUBILITY OF CALCIUM SILICATE HYDRATES (C-S-H) I 6 2 1 RELEVANCE OF CEMENT PHASES IN RADIOACTIVE WASTE MANAGEMENT I 6 2 2 THERMODYNAMIC MODELLING OF C-S-H AND ITS LIMITATIONS I 6 2 3 GEOCHEMICAL MODELLING OF C-S-H SYSTEMS OF INTEREST IN RADIOACTIVE WASTE MANAGEMENT I 6 2 4 CONCLUSIONS STRUCTURAL INCORPORATION OF TRIVALENT ACTINIDES/LANTHANIDES INTO CALCITE I 6 3 1 THE RELEVANCE OF CALCITE FOR RADIOACTIVE WASTE MANAGEMENT I 6 3 2 MACROSCOPIC INFORMATION RELATED TO THE SORPTION OF F-ELEMENTS INTO CALCITE I 6 3 3 SPECTROSCOPIC INFORMATION ON THE INCORPORATION OF F-ELEMENTS INTO THE CALCITE STRUCTURE I 6 3 4 THERMODYNAMIC MODELLING OF THE EU(III)/CALCITE SYSTEM I 6 3 5 CONCLUSIONS SOLID SOLUTIONS IN THE NUCLEAR FUEL CYCLE I 6 4 1 THE APPLICABILITY OF AQ-SS THERMODYNAMICS TO SPENT NUCLEAR FUEL I 6 4 2 MAIN RESULTS FROM THE CHARACTERISATION OF UO2 SPENT NUCLEAR FUEL I 6 4 3 APPLICATION OF AQ-SS THERMODYNAMICS TO SPENT FUEL DISSOLUTION DATA I 6 4 4 CONCLUSIONS I 7 REPORT CONCLUSIONS PART II: THEORY, EXPERIMENTAL ASPECTS AND CASES FOR STUDY II 1 THEORETICAL ASPECTS OF SOLID SOLUTIONS AND THEIR SOLUBILITY THEORY OF SOLID SOLUTIONS II 1 1 1 INTRODUCTION II 1 1 2 THERMODYNAMIC FORMALISM II 1 1 3 THE ENTROPY OF MIXING II 1 1 4 REGULAR, SUBREGULAR AND GENERALISED MIXING MODELS II 1 1 5 PHASES WITH DIFFERENT STRUCTURES II 1 1 6 ORDER-DISORDER PHENOMENA GENERAL COMMENTS AN EXAMPLE: CARBONATES WITH CALCITE AND DOLOMITE STRUCTURE METHODS AND TOOLS FOR THERMODYNAMIC DESCRIPTION OF AQUEOUS-SOLID SOLUTION (AQ-SS) EQUILIBRIA II 1 2 1 DEFINITIONS AND BASIC THERMODYNAMICS RELATIONS MOLE FRACTION SCALE MOLALITY SCALE AQUEOUS ACTIVITY COEFFICIENTS SIT MODEL PITZER MODEL EXTENDED UNIQUAC MODEL GAS MIXTURES AND GAS SOLUBILITY SOLID SOLUBILITY UNIFIED THEORY OF IONIC SOLID SOLUTION SOLUBILITIES MULTICOMPONENT IONIC AQ-SS SYSTEM II 1 2 2 LIPPMANN DIAGRAMS, A TOOL TO VISUALISE BINARY AQ-SS SYSTEMS EXAMPLE OF THE USE OF LIPPMANN DIAGRAMS II 1 2 3 LAW OF MASS ACTION (LMA) METHOD FOR COMPUTING EQUILIBRIUM SPECIATION II 1 2 4 GIBBS ENERGY MINIMISATION (GEM) METHOD GEM IPM ALGORITHM GEM DUAL-THERMODYNAMIC CALCULATIONS IN FORWARD MODELLING MULTIPLE SOLID SOLUTIONS AND MISCIBILITY GAPS METHODS OF RETRIEVAL OF STOICHIOMETRY, STABILITY OF SOLID SOLUTION END-MEMBERS, AND PARAMETERS OF NON-IDEAL MIXING (INVERSE MODELLING) II 1 3 1 THE “ACTIVITY RATIOS” TECHNIQUE II 1 3 2 DUAL THERMODYNAMIC RETRIEVAL CALCULATIONS ALGORITHM OF THE SINGLE DUAL-TH CALCULATION AT EQUILIBRIUM RETRIEVAL OF ACTIVITY COEFFICIENTS AND MIXING PARAMETERS RETRIEVAL OF END-MEMBER STANDARD GIBBS ENERGY AND SOLUBILITY PRODUCT AT EQUILIBRIUM RETRIEVAL OF APPARENT MOLAR GIBBS ENERGY FOR A TRACE END-MEMBER DUAL-TH RETRIEVAL CALCULATIONS AT MINIMUM STOICHIOMETRIC SATURATION STATISTICAL DUAL-TH CALCULATIONS EXAMPLE: EUIII IN CALCITE II 1 3 3 GRAPHICAL FITTING AND REGRESSION METHODS WEIGHTED LEAST-SQUARES AND BAYESIAN ESTIMATION TECHNIQUES II 1 3 4 RETRIEVAL OF EXCESS GIBBS ENERGY FROM ELECTROCHEMICAL MEASUREMENTS II 1 3 5 ESTIMATION OF INTERACTION PARAMETERS FROM THE POSITION OF MISCIBILITY GAPS MISCIBILITY GAP DATA CRITICAL MIXING-POINT DATA II 1 3 6 ESTIMATION OF INTERACTION PARAMETERS FROM DISTRIBUTION COEFFICIENTS II 2 EXPERIMENTAL AND ANALYTICAL ASPECTS CO-PRECIPITATION EXPERIMENTS IN AQUEOUS SOLUTION II 2 1 1 LIMITATIONS AND POINTS TO NOTICE II 2 2 1 THERMODYNAMIC EQUILIBRIUM SOLUBILITY II 2 2 2 STOICHIOMETRIC SATURATION SOLID PHASE CHARACTERISATION II 3 CASES OF SPECIFIC INTEREST IN RELEVANT SYSTEMS SULPHATES: THE BARITE ISOSTRUCTURAL FAMILY AND THE INCORPORATION OF RADIOACTIVE ISOTOPES OF RA II 3 1 1 INTRODUCTION TO THE BARITE ISOSTRUCTURAL FAMILY II 3 1 2 THE RADIUM AND ITS INCORPORATION INTO THE BARITE SOLID SOLUTION FAMILY: ENVIRONMENTAL IMPLICATIONS THE RADIUM-BARIUM RELATIONSHIP IN NATURAL AND ANTHROPO- GENIC ENVIRONMENTS NUMERICAL MODELLING INVOLVING (BA,RA)SO4 SOLID SOLUTIONS II 3 1 3 CONCLUSIONS CASES STUDY/CEMENT PHASES – SOLUBILITY OF CALCIUM SILICATE HYDRATES (C-S-H) II 3 4 1 INTRODUCTION II 3 4 2 SOLID SOLUTION IN NUCLEAR MATERIALS URANINITE AND NON IRRADIATED FUEL IRRADIATED UO2 MIXED OXIDE (MOX) AND ROCK-LIKE OXIDE (ROX) II 3 4 3 APPLICATION OF AQ-SS THERMODYNAMICS TO SPENT FUEL DISSOLUTION EXPERIMENTAL DATA STRONTIUM BARIUM NEPTUNIUM PLUTONIUM LANTHANIDES II 3 4 4 FINAL REMARKS