Supercritical Fluid Supercritical Fluid ExtractionExtraction

Intermolecular ForcesIntermolecular Forces

Dipole-Dipole InteractionsDipole-Dipole Interactions London Dispersion ForcesLondon Dispersion Forces Hydrogen BondingHydrogen Bonding

Dipole-Dipole InteractionsDipole-Dipole Interactions

Some molecules have an uneven Some molecules have an uneven distribution of charge; these are called distribution of charge; these are called polar molecules.polar molecules.

Polar molecules attract one another when Polar molecules attract one another when the partial positive charge on one molecule the partial positive charge on one molecule is near the partial negative charge on is near the partial negative charge on another moleculeanother molecule

London Dispersion Forces London Dispersion Forces

Instantaneous uneven electron distributions Instantaneous uneven electron distributions in a molecule can cause induced dipole-in a molecule can cause induced dipole-dipole effects called London Dispersion dipole effects called London Dispersion Forces. Forces.

Hydrogen BondingHydrogen Bonding

By far the strongest intermolecular forceBy far the strongest intermolecular force A hydrogen atom in a polar bond can A hydrogen atom in a polar bond can

experience in attractive force with a experience in attractive force with a neighboring Electronegative atom. neighboring Electronegative atom.

This is especially applicable when a This is especially applicable when a Hydrogen atom and highly electronegative Hydrogen atom and highly electronegative atom are bonded in a molecule; one of the atom are bonded in a molecule; one of the most polar bonds known. most polar bonds known.

Energy of SolvationEnergy of Solvation

The energy of forces The energy of forces between the molecules of between the molecules of the solute are in contest the solute are in contest with the energy of forces with the energy of forces between molecules of between molecules of solute and solvent.solute and solvent.

Also added to the Energy Also added to the Energy of solvation is the energy of solvation is the energy needed to make a cavity needed to make a cavity in the solvent for each in the solvent for each solute molecule to be solute molecule to be surrounded.surrounded.

Carbon DioxideCarbon Dioxide

Carbon Dioxide is used in Carbon Dioxide is used in Supercritical fluid studies because Supercritical fluid studies because it’s critical point is in an easily it’s critical point is in an easily reached range.reached range.

At its normal Gaseous state Carbon At its normal Gaseous state Carbon Dioxide is an extremely bad solvent, Dioxide is an extremely bad solvent, but as a liquid it has much better but as a liquid it has much better solvent capabilities. solvent capabilities.

Phase DiagramPhase Diagram

Supercritical FluidSupercritical Fluid

Both Gas and liquid phases have the same densities in this range. Both Gas and liquid phases have the same densities in this range. Carbon Dioxide is normally used since it’s critical point is at 73.8 bar and Carbon Dioxide is normally used since it’s critical point is at 73.8 bar and

31.1 degree Celsius, a very easily reached condition31.1 degree Celsius, a very easily reached condition

Two Separate phases of Carbon Dioxide

One Supercritical Phase Of Carbon Dioxide

UsesUses

Decaffeinating coffee as well as Decaffeinating coffee as well as Sewage Treatment.Sewage Treatment.

Control over Density, and Solvation.Control over Density, and Solvation. Differentiates between enantiomers, Differentiates between enantiomers,

paramount in producing medicines.paramount in producing medicines.

Experiment PurposeExperiment Purpose

Show proof that a tailor made Show proof that a tailor made molecule could be made to enhance molecule could be made to enhance extraction. extraction.

Solves the problem of low extraction Solves the problem of low extraction results that plagues CO2 extraction. results that plagues CO2 extraction.

Experiment SetupExperiment Setup

Uses a CO2 extraction device made in the Uses a CO2 extraction device made in the lab to run super critical CO2 through a lab to run super critical CO2 through a powder.powder.

After the CO2 is bubbled through Methanol After the CO2 is bubbled through Methanol and this solution is run in a HPLC to and this solution is run in a HPLC to discover the contents.discover the contents.

Different mixtures of chemicals are Different mixtures of chemicals are extracted to see how the chemicals affect extracted to see how the chemicals affect each other’s solvation.each other’s solvation.

ResultsResults

Certain interactions cause a decent Certain interactions cause a decent increase in product:increase in product:

Pi-Pi benzene ring interactionPi-Pi benzene ring interaction Hydrogen bonding between the Hydrogen bonding between the

moleculesmolecules Why?Why?

THE ENDTHE END

Any Questions?Any Questions?