Mixer Settler
Feed (aqueous)
F = 5.0 m³/h
z = 0.50 mol/L
Solvent (organic)
E = 5.0 m³/h
0 mol/L
Extract (organic)
E = 5.0 m³/h
y = 0.50 mol/L
Residue (aqueous)
F = 5.0 m³/h
x = 0.25 mol/L
mixed phases
fraction of uranyl nitrate extracted
50.0%
0.50
5.0
5.0
5.0

Directions

This simulation models a single equilibrium stage for the solvent extraction of uranyl nitrate from an aqueous feed, using tributyl phosphate (TBP) dissolved in kerosene as the organic extractant. The aqueous feed and the organic extractant are combined in a mixer, and the resulting two-phase mixture is separated in a settler: the organic (extract) phase leaves from the top, and the aqueous (residue, or raffinate) phase leaves from the bottom.

Use the sliders to change:

  • z – the molar concentration of uranyl nitrate in the aqueous feed (0.1–1 mol/L)
  • F – the volumetric flow rate of the aqueous feed (1–10 m³/h)
  • E – the volumetric flow rate of the organic extractant (1–10 m³/h)
  • D – the equilibrium distribution coefficient relating the extract and residue concentrations, y = Dx, where D ranges from 1 to 10

The diagram updates immediately to show the resulting extract concentration (y) and residue concentration (x), along with the fraction of uranyl nitrate recovered into the extract. See the Details panel for the mass-balance derivation.

Details

The aqueous feed (flow rate F, uranyl nitrate concentration z) and the organic extractant (flow rate E, uranyl nitrate concentration 0) are contacted in the mixer. The two immiscible liquid phases are then disengaged in the settler. Because the two phases are immiscible and the solute is present at low concentration, the aqueous and organic volumetric flow rates are each essentially unchanged across the stage.

An overall mass balance on uranyl nitrate over the mixer–settler unit gives:

The extract and residue leaving the settler are in equilibrium, with the distribution of uranyl nitrate between the organic and aqueous phases described by:

Substituting the equilibrium relation into the mass balance and solving for the residue concentration:

The extract concentration then follows from the equilibrium relation:

The fraction of the uranyl nitrate in the feed that is recovered in the extract is:

Increasing the extractant flow rate E or the distribution coefficient D drives more uranyl nitrate into the extract phase and lowers the residue concentration x.

About

This simulation was created in the Department of Chemical and Biological Engineering at University of Colorado Boulder for LearnChemE.com by John L. Falconer using Claude AI. It was prepared with financial support from the National Science Foundation (DUE 2336987 and 2336988). Address any questions or comments to LearnChemE@gmail.com.