Advances in Electrolyte Thermodynamics
Peiming Wang, Margaret Lencka, Ronald Springer, Jerzy Kosinski, Jiangping Liu, Ali Eslamimanesh, Gaurav Das, and Andre Anderko
OLI Simulation Conference 2016
Conference organization by Scope
• Structure of OLI’s thermodynamic models • Progress in thermodynamic modeling • Results for selected chemistries • How predictive can we be? • Dielectric constant • Status of databanks • Plans for the future Structure of Thermophysical Property Frameworks Aqueous (AQ) Framework Mixed-Solvent Electrolyte (MSE) Framework Other properties AQ thermodynamics MSE thermodynamics Other properties Standard state: HKF Electrical EOS (via fitting Standard state: HKF Electrical EOS (direct) conductivity equations as default) conductivity
GEX: Bromley-Zemaitis GEX: MSE Viscosity Viscosity I < 30 m; xorg < 0.3 No concentration limit
Self- Solids: Solids: Self- diffusivity Equilibrium constants Thermochemical diffusivity for SLE properties
Gas phase: SRK Gas phase: SRK Thermal equation of state equation of state conductivity
nd nd Surface 2 liquid phase: SRK 2 liquid phase: MSE tension EOS (same as for gas GEX model (same as for phase) aqueous phase) Interfacial Interfacial phenomena: Interfacial phenomena: tension Ion exchange, surface Ion exchange, surface complexation, complexation, Dielectric molecular adsorption molecular adsorption constant Progress in Thermodynamic Modeling: Inorganic systems • Actinide chemistry • U(IV, VI), Np(IV, V, VI), Pu(III, IV, V, VI), Am(III), Cm(III) • Oxides, hydroxides, carbonates, chlorides, nitrates • Redox
• Surface complexation on MnOx • Rare-earth element chemistry • REE chlorides, sulfates, carbonates, phosphates, hydroxides, acetates, citrates, gluconates • Transition metal chemistry • Ru, Rh, Tc fundamental chemistry • Ag nitrate, sulfate systems • Ni sulfate systems
Progress in Thermodynamic Modeling: Inorganic systems • Post-transition metal chemistry • Pb silicate, molybdate, tungstate, acetate, formate, nitrate • Al nitrate and sulfate with corresponding acids
• AlF3 - NaF • Tellurium chemistry • Oxides, hydroxides, nitrates, compounds with Na, Zr, Mo • Silicate chemistry • Na aluminosilicates, Ca, Mg, Zn, Al, Pb silicates • Sodium phosphate chemistry
• Chemistry of solutes in CO2 environments 0 • S , NOx, SOx in CO2 • High-pressure, high-temperature scaling
• BaSO4, CaCO3
Progress in Thermodynamic Modeling: Inorganic systems
• C – N – H chemistry • Melamine, melam, ammeline, ammelide, cyanuric acid • Cyanate chemistry • Chelant chemistry • EDTA and IDA • Potash chemistry • K2SO4 – KCl • Li2SO4 • Other salts • NaBr
• Revisions of Sr – SO4 – CO2 chemistry • Revisions of FeS and FeCO3 chemistry Progress in Thermodynamic Modeling: Organic systems • Hydrocarbon chemistry • PVT properties of hydrocarbons • Methanol-hydrocarbon systems
• CO2 – hydrocarbon – H2O systems • H2S – hydrocarbon – H2O systems • Methane – higher hydrocarbon systems
• Methane – H2O – salt mixtures • Organic acid chemistry • Maleic acid and anhydride • Acetic and formic acids with hydrocarbons • Monoethylene glycol chemistry refinements • PVT properties • Effect on SrSO4, FeSO4, FeCO3 Thermodynamics of Actinides
Solubility of Am(OH)3 as a function of pH and Cl- • Trivalent actinides show similar phase behavior • Weak complexation with Cl-
• Moderate increase in Speciation of Cm(III) solubility due to Cl as a function of Cl- complexation • Model is consistent with both solubility and TRLFS speciation data
Speciation of Cm(III) Thermodynamics as a function of CO3/HCO3 of Actinides
• Dual effect of CO3/HCO3 • Strong complexation • Formation of carbonate solids
Solubility of Am as a function of pH and CO2 How does redox affect solubility? Behavior of Np(VI) . Np(VI) is unstable in acidic and neutral environments . May be easily reduced to Np(V) and Np(IV)
Solubility and speciation calculated by including redox equilibria At near-neutral conditions, Np(V) predominates (red lines) solubility of Np(VI) is governed by reductive dissolution At alkaline conditions, Np(VI) predominates (blue lines) Surface Complexation Np(V) on hausmanite (Mn3O4) in the presence of CO2
• Double-layer surface complexation model • Originally parameterized for hydrous ferric oxide using AQ bulk thermodynamics NpO + 2 NpO (CO ) -Mn O ·H O3- 2 3 2 3 4 2 • Applied to actinide 4- NpO2(CO3)2-Mn3O4·OH sorption on MnO2 (synthetic, biogenic), NpO -Mn O ·OH0 2 3 4 MnOOH, Mn3O4 using 2- NpO2CO3-Mn3O4·OH MSE bulk
- thermodynamics NpO2CO3 • Explains relationship
NpO (CO ) 3- between bulk phase and NpO OH 2 3 2 2 5- NpO2(CO3)3 surface speciation Thermodynamics of Rare Earth Elements • DOE’s Critical Fundamentals: Phase behavior of LaCl3 – H2O Material Institute Sokolova (1988) 20 Sokolova (1988) Sokolova (1988) LaCl .H O Sokolova (1988) • Diversifying supply: 3 2 . 18 LaCl3 3H2O Friend (1940) Herkot (1989) Powell (1960) Improving methods 16 Nikolaev (1971/67/77/78/69) Zhuravlev (1972/74a) Tang (1982) to extract REEs from 14 Storozhenko (1988/86) Khutorskoi (1968/68a,b) Sheveleva (1973a,b/58/61/68) Chen, Y. G. (2003) ores and waste 12 Chen, J. X. (1990) Berecz (1990) Zelikman (1971) 10 Volkov (1970) • Recycling and
LaCl3 Zholalieva (1976/78) Alieva (1970) m 8 Brunisholz (1969) increasing efficiency LaCl .7H O Petelina (1969) 3 2 Sergeeva (1976) 6 Voigt (1993) of materials use . Cui (1997) LaCl3 9H2O . Fischer (1968) LaCl3 10H2O Kost (1980) 4 Li (1995) Liu (1999) • OLI’s role Shi (1988) 2 Shirai (1981) Sorokina (1977) Ice Spedding (1977) • Provide tools for 0 Wang (2007) Zwietasch (1984) -70 -40 -10 20 50 80 110 140 170 200 Voigt (1993) predicting phase and o Voigt (1993) t / C chemical equilibria to optimize new or improved processes
Thermodynamics of Rare Earth Elements: Application to Bioseparations • Engineered cell surfaces used to separate REEs from aqueous solutions • Lanthanide binding tags bind REEs • Complexing agents are necessary to recover absorbed REEs
* Park et al. Environ. Sci. Technol. 2016, 50 (5), 2735-2742. • What eluents will work? 1 System: pH = 5 TbCl3 10 µm CaCl2 0 or 150 mm pH = 6.1 0.8 Na acetate 0-50 mm NaCl 10E-3 m pH = 5 + CaCl2 Complexation pH = 6.1 + CaCl2 0.6 of Tb 0.4 Ca competes with Tb for complexation with
0.2 acetate. • Complexation is Fraction of Tb Tb uncomplexed Fraction of 0 necessary to desorb 0 10 20 30 40 50 Eluent (Na acetate) / mM REEs Acetate is inefficient for desorption and
Ca interferes with desorption 1 • Predicted fraction of System: pH = 5 - No CaCl2 Tb uncomplexed in TbCl 10 µm 0.8 3 pH = 6.1 - No CaCl2 CaCl2 0 or 150 mm solution parallels the Na citrate 0-50 mm pH = 5 + CaCl2 0.6 NaCl 10E-3 m pH = 6.1 + CaCl2 observed fraction of 0.4 Tb that remains bound Ca does not effectively 0.2 compete with Tb for to the surface
complexation with citrate. Fraction of Tb uncomplexed Tb of Fraction 0 0 5 10 15 20 Eluent (Na citrate) / µM Small concentration of citrate is sufficient
for desorption Modeling systems containing elemental sulfur
• What are the chemical transformations of SOx, NOx H2S, and O2 in CO2 transportation pipelines? • Hence, what are the limits of safe operation? 0 • Part 1: Model the solubility of S in CO2-rich phases in order to predict whether solid S0 can drop out 0 0 0 • Systems analyzed: Pure S , S – H2O, S – CO2 0 • Speciation of sulfur S 8 0 • Species up to S 20 have been detected 0 0 • S 1 through S 8 have been assumed 0 • S 8 is dominant at moderate conditions in gas phase • Lower multimers become prevalent at higher temperatures 0 • In liquid phase, S 8 predominates 0 • In CO2 phase, solvated S – CO2 species appears 0 Solubility of S in CO2 1E-03
1E-04
1E-05 Kennedy and Wieland (1960)
, mole fraction mole , Gu etal (1993)
8 Serin etal (2010) S Dugstad et al (2015) Svenningsen et al (2016) 1E-06 25C 45C 60C 90C 110C 120C 1E-07 50 100 150 200 250 300 350 400 450 Pressure, atm • Two segments of solubility curves at each T corresponding to gas (or gas-like) and liquid (or liquid-like) CO2
• Transition is sharp for subcritical CO2 and gradual for supercritical CO2
Pushing the Limits of Complexity: NaOH + H3PO4 + H2O . Temperature range: to 350C . Chemical equilibria -3 -2 • PO4 , HPO4 , -1 H2PO4 , etc. • Association of + -1 Na /H2PO4 . Phase equilibria • Vapor-liquid • Solid-liquid, sodium pyrophosphate (T > 250C) • Liquid-liquid (T > 270C) Liquid-Liquid Equilibria at High Temperatures • Increased ion pairing at high T drives liquid phase demixing • Lower critical temperature
• LLE depends on the Na/P ratio • If the solubility drops with T, LLE will not appear How to Deal with Near- Critical Behavior?
• Classical models do not represent near critical behavior • Crossover models would not be practical for highly speciated reactive systems • A local model gives a fully quantitative representation of LLE in the high-T region Modeling Silicates: Importance of Metastable Phases PbO – SiO2 – H2O
1.E-01 SiO2 (am) 1.E-02 SiO2 (quartz) PbSiO3 1.E-03 Pb SiO SiO2 amorphous 2 4 1.E-04 SiO2 quartz PbSiO3 alamosite
1.E-052 Pb2SiO4 Pb11Si3O17 Pb11Si3O17 PbO yellow
m m SiO 1.E-06 PbO red
1.E-07 PbO red 1.E-08 PbO yellow 25 C 300 C 1.E-09 m PbO 1.E-05 1.E-04 1.E-03 1.E-02
• Multiple competing silicate phases • Both stable and metastable phases
Mixtures of Hydrocarbons with Acetic Acid
• Reproducing vapor-liquid and liquid-liquid equilibria • Generalization of parameters for normal alkanes to handle pseudocomponents
1 70 acetic acid + hexane + water C7 P=1atm. 0.9 C9 fuse&Iguchi (1970), 25°C 60 C10 Rao&Rao (1957), 31°C 0.8 50 C11 C12 0.7 40
0.6 30
0.5
C
° 20
0.4
t / / t x acetic acid acetic x 10 0.3
0.2 0
0.1 -10
0 -20 0 0.2 0.4 0.6 0.8 1 0.2 0.4 0.6 0.8 1 x hexane x acetic acid LLE for HAc – hexane – H O ternary LLE for HAc – hydrocarbon binaries: 2 Miscibility gap increases with carbon number How Predictive Is the Model?
• Desirable scenario: • Develop model parameters based on binary data • Predict the behavior of multicomponent systems • If the model is physically correct, this works • Caveat: As long as there is no chemistry change in a multicomponent system • Two cases to illustrate predictions Case 1: Mixed NaCl – H O 2 Chloride - Sulfate NaCl Systems NaCl ·2H2O • Binary systems • Regressed parameters Ice • Cation-anion interaction parameters • Thermochemical properties of solids
Na2SO4 – H2O • Based on experimental Na2SO4 (rhombic) data • Solubilities
Na2SO4 ·10H2O • VLE/osmotic coefficients Na2SO4 (monoclinic) • Activity coefficients • Enthalpies of dilution • Heat capacity Ice • Density
Case 1: Mixed Chloride - Sulfate Systems
• Ternary system NaCl - Na2SO4 – H2O • Regressed parameters - 2- • Cl - SO4 interactions • Second-order correction • Binary in nature but obtained from ternary data • Full complexity of ternary behavior is reproduced Case 1: Mixed Chloride - Sulfate Systems: Pure Prediction • Behavior of ternary KCl – K2SO4 – H2O system is accurately predicted without any further parameter adjustment • Parameters are fully transferable • No new ternary chemical effects
Case 2: Mixed Al NaF – H2O and Na Salts • Binary and ternary systems • Interactions regressed • Cation-anion parameters • Al3+ - Na+ cation-cation parameters
AlF3 – H2O
AlF3 Case 2: Mixed Al and Na Salts
AlF3.3H2O AlF3 – NaF – Na Al F 5 3 14 H2O
NaF
Na3AlF6
• Although NaF and AlF3 are fairly soluble, solubility in the ternary system AlF3 – NaF – H2O is dramatically lower • Specific ternary chemistry effect: Formation of sparingly soluble double salts
• Cryolite, Na3AlF6, and chiolite, Na5Al3F14 • Ternary chemical effects need to be incorporated but cannot be simply predicted from the properties of binary or other ternary systems
Predicting Dielectric Constant of Mixtures
• Calculating polarization • Kirkwood theory
2 1 2 1 4 N g A p 9 3v 3kT • Mixing rule for polarization n n xi x j vp ij p i j m n xi v i i 1 1 vp v p v p 1 k ij 2 i i j j ij Monoethylene glycol – water • Good approximation without binary parameters
Predicting NaCl at 25 C Dielectric Constant
• Effect of ionic components
s0 s 1 Ai xi ln(1 Bi I X ) ions
NaCl at various T • Predicts universal decrease with ionic composition • Effect of ion pairs is more complex AQ and MSE Databanks: A Comparison
Databank Aqueous model: Mixed-solvent Number of species electrolyte model: Number of species General-purpose (process chemistry) PUBLIC MSEPUB 5407 2590 (5407 in 10/2014) (2150 in 10/2014) Geochemical (solids formed on a 138 135 geological timescale) Corrosion (corrosion-related solids) 367 321 Urea (enabling urea-related reactions) Not available 8 Surface complexation, double layer 120 57 Ion exchange 13 0 Ceramics (ceramic solids) 36 Not applicable – included in MSEPUB Low temperature (extension to 227 Not relevant (MSEPUB calculate properties below 0 C) works below 0 C) Plans for the Future • Thermodynamics of rare-earth elements • Applications to diversifying the supply, separation and recycling • High-pressure, high-temperature scaling
• Solubility of ZnS, PbS and CaSO4 in produced water environments
• Chemistry of CO2 transmission • Predicting formation of corrosive phases in dense-phase CO2 • Chemistry of silicates • Application to silica removal processes including surface complexation and kinetics
Plans for the Future • Potash chemistry
• K – Na – Li – Ca – SO4 – Cl systems • Amines and amine hydrochlorides • Towards further improvement of predictions • Finalizing improvements of hydrocarbon chemistry • Mutual diffusivity • Applications to mass-transfer separations • Future client-driven projects