Fluid Properties for New Technologies: Electrolyte Systems

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Fluid Properties for New TechnologiesElectrolyte
Systems

• Andrzej Anderko
• OLI Systems, Inc.
• 108 American Road, Morris Plains, NJ 07950

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Technologies of interest

ESP Environmental Simulation
Flow Assurance SW Upstream Scale/ Corrosion/Produc
tion Chem
CSP Corrosion Simulation
CrySP Crystallization Simulation
Thermophysical properties and chemistry of
electrolytes
Process Simulator Interfaces
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Technology highlights

• From electrolyte thermodynamics to corrosion
  simulation Importance of the properties of
  electrolyte systems
• Fluid properties for supercritical water
  oxidation
• Electrolyte properties for designing syntheses of
  inorganic materials
• Soil/aqueous systems Combined effects of
  adsorption, solubility, phase splitting, etc.
• Database needs

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Prediction of corrosion Role of thermophysical
properties

• Thermodynamic equilibrium calculations
• What species exist in the system?
• What are the activities of corrosive species?
• Computation of transport properties
• Diffusivity and viscosity are necessary to model
  processes related to the mass transfer of species
  to and from a corroding interface
• Thermodynamic and transport properties are used
  as input to electrochemical kinetics models

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Prediction of corrosion Role of thermodynamic
properties

• Example 1 Corrosivity of acids depends on the
  activity of protons
• Example 2
• Anhydrous HF is not corrosive
• Aqueous HF is very corrosive
• Transition between the two regimes depends on
  thermodynamic speciation

HCl
H2SO4
H3PO4
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Properties for supercritical water oxidation

• Problem Precipitation of salts limits the
  operation envelope
• Other properties (VLE, densities, enthalpies) are
  also needed

NaCl H2O
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Properties for supercritical water oxidation

• Methodology
• Computation of vapor-liquid and solid-liquid
  equilibria
• Kinetic modeling of oxidation processes
• Current status
• An accurate equation of state is available, but
  it has been parameterized for a limited number of
  systems
• Limitations
• Lack of phase equilibrium data for many systems
• Behavior of multicomponent systems is poorly
  known
• Little is known about transport properties,
  especially in the presence of salts

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Properties for designing syntheses of advanced
inorganic materials

• Example Hydrothermal synthesis of ceramics
  precipitation of multicomponent oxides from
  complex aqueous systems
• Problem
• How to optimize the conditions of the
  synthesis?

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Properties for designing syntheses of advanced
inorganic materials

• Methodology
• Equilibrium computations for multicomponent
  electrolyte systems with multiple competing solid
  phases
• Current status
• Syntheses of several piezoelectric ceramics have
  been successfully optimized and implemented
• Limitations
• Lack of thermochemical data for many complex
  solids (e.g. multicomponent oxides) and
  secondarily, aqueous species
• Insufficiently advanced methods for estimating
  thermochemical properties

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Soil/Aqueous Systems

• Methodology
• Adsorption phenomena (ion exchange, molecular
  adsorption, surface complexation)
• Phase equilibria in the bulk (e.g., partitioning
  between aqueous and NAPL phases)
• Solubility and speciation effects in the aqueous
  phase
• Current status
• A comprehensive model has been developed and
  verified against experimental data
• Limitations
• Parameters cannot always be determined because of
  insufficient characterization of systems of
  interest
• Kinetic effects are not well characterized

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Database needs for mixtures

• Comprehensive, computerized collections exist for
  nonelectrolyte systems (Dechema, TRC)
• Several printed data sources exist for
  electrolyte systems at normal conditions.
  However,
• No computerized collection is available
• Many valuable sources have not been updated in
  decades
• No database exists for high-temperature and
  supercritical electrolyte systems