solubility¶
All data and methods for estimating a chemical’s solubility.
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thermosteam.properties.solubility.
solubility_parameter
(T=298.15, Hvapm=None, Vml=None, CASRN='', AvailableMethods=False, Method=None)[source]¶ This function handles the calculation of a chemical’s solubility parameter. Calculation is a function of temperature, but is not always presented as such. No lookup values are available; either Hvapm, Vml, and T are provided or the calculation cannot be performed.
\[\delta = \sqrt{\frac{\Delta H_{vap} - RT}{V_m}}\]- Parameters
T (float) – Temperature of the fluid [k]
Hvapm (float) – Heat of vaporization [J/mol/K]
Vml (float) – Specific volume of the liquid [m^3/mol]
CASRN (str, optional) – CASRN of the fluid, not currently used [-]
- Returns
delta (float) – Solubility parameter, [Pa^0.5]
methods (list, only returned if AvailableMethods == True) – List of methods which can be used to obtain the solubility parameter with the given inputs
- Other Parameters
Method (string, optional) – A string for the method name to use, as defined by constants in solubility_parameter_methods
AvailableMethods (bool, optional) – If True, function will determine which methods can be used to obtain the solubility parameter for the desired chemical, and will return methods instead of the solubility parameter
Notes
Undefined past the critical point. For convenience, if Hvap is not defined, an error is not raised; None is returned instead. Also for convenience, if Hvapm is less than RT, None is returned to avoid taking the root of a negative number.
This parameter is often given in units of cal/ml, which is 2045.48 times smaller than the value returned here.
Examples
Pentane at STP
>>> solubility_parameter(T=298.2, Hvapm=26403.3, Vml=0.000116055) 14357.681538173534
References
- 1
Barton, Allan F. M. CRC Handbook of Solubility Parameters and Other Cohesion Parameters, Second Edition. CRC Press, 1991.
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thermosteam.properties.solubility.
solubility_eutectic
(T, Tm, Hm, Cpl=0, Cps=0, gamma=1)[source]¶ Returns the maximum solubility of a solute in a solvent.
\[ \begin{align}\begin{aligned}\ln x_i^L \gamma_i^L = \frac{\Delta H_{m,i}}{RT}\left( 1 - \frac{T}{T_{m,i}}\right) - \frac{\Delta C_{p,i}(T_{m,i}-T)}{RT} + \frac{\Delta C_{p,i}}{R}\ln\frac{T_m}{T}\\\Delta C_{p,i} = C_{p,i}^L - C_{p,i}^S\end{aligned}\end{align} \]- Parameters
T (float) – Temperature of the system [K]
Tm (float) – Melting temperature of the solute [K]
Hm (float) – Heat of melting at the melting temperature of the solute [J/mol]
Cpl (float, optional) – Molar heat capacity of the solute as a liquid [J/mol/K]
Cpls (float, optional) – Molar heat capacity of the solute as a solid [J/mol/K]
gamma (float, optional) – Activity coefficient of the solute as a liquid [-]
- Returns
x – Mole fraction of solute at maximum solubility [-]
- Return type
float
Notes
gamma is of the solute in liquid phase
Examples
From [1]_, matching example
>>> solubility_eutectic(T=260., Tm=278.68, Hm=9952., Cpl=0, Cps=0, gamma=3.0176) 0.24340068761677464
References
- 1
Gmehling, Jurgen. Chemical Thermodynamics: For Process Simulation. Weinheim, Germany: Wiley-VCH, 2012.
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thermosteam.properties.solubility.
Tm_depression_eutectic
(Tm, Hm, x=None, M=None, MW=None)[source]¶ Returns the freezing point depression caused by a solute in a solvent. Can use either the mole fraction of the solute or its molality and the molecular weight of the solvent. Assumes ideal system behavior.
\[ \begin{align}\begin{aligned}\Delta T_m = \frac{R T_m^2 x}{\Delta H_m}\\\Delta T_m = \frac{R T_m^2 (MW) M}{1000 \Delta H_m}\end{aligned}\end{align} \]- Parameters
Tm (float) – Melting temperature of the solute [K]
Hm (float) – Heat of melting at the melting temperature of the solute [J/mol]
x (float, optional) – Mole fraction of the solute [-]
M (float, optional) – Molality [mol/kg]
MW (float, optional) – Molecular weight of the solvent [g/mol]
- Returns
dTm – Freezing point depression [K]
- Return type
float
Notes
MW is the molecular weight of the solvent. M is the molality of the solute.
Examples
From [1]_, matching example.
>>> Tm_depression_eutectic(353.35, 19110, .02) 1.0864594900639515
References
- 1
Gmehling, Jurgen. Chemical Thermodynamics: For Process Simulation. Weinheim, Germany: Wiley-VCH, 2012.