Solvent Extraction
SOLVENT EXTRACTION
Solvent extraction, also known as liquid extraction and partitioning, is a method to separate compounds based on their relative solubility in two different immiscible liquid, usually water and organic solvent. It is an extraction from one liquid phase to another liquid phrase. Liquid extraction is a basic technique in chemical laboratories, where it is performed using a separator funnel. This type of process is commonly performed after a chemical reaction as part of the work-up. Liquid–liquid extraction is possible in non-aqueous systems: In a system consisting of a molten metal in contact with molten salts, metals can be extracted from one phase to the other. This is related to a mercury electrode where a metal can be reduced, the metal will often then dissolve in the mercury to form an amalgam that modifies its electrochemistry greatly. For example, it is possible for sodium cations to be reduced at a mercury cathode to form sodium amalgam, while at an inert electrode (such as platinum) the sodium cations are not reduced. Instead, water is reduced to hydrogen. A detergent or fine solid can be used to stabilize an emulsion, or third phase.
MEASURES OF EFFECTIVENESS
Distribution ratio
In solvent extraction, a distribution ratio is often quoted as a measure of how well-extracted a species is. The distribution ratio is equal to the concentration of a solute in the organic phase divided by its concentration in the aqueous phase. Depending on the system, the distribution ratio can be a function of temperature, the concentration of chemical species in the system, and a large number of other parameters.
Separation factor
The separation factor is one distribution ratio divided by another; it is a measure of the ability of the system to separate two solutes.
Decontamination factor
This is used to express the ability of a process to remove a contaminant from a product.
Slopes of graph
The easy way to work out the extraction mechanism is
Solvent extraction, also known as liquid extraction and partitioning, is a method to separate compounds based on their relative solubility in two different immiscible liquid, usually water and organic solvent. It is an extraction from one liquid phase to another liquid phrase. Liquid extraction is a basic technique in chemical laboratories, where it is performed using a separator funnel. This type of process is commonly performed after a chemical reaction as part of the work-up. Liquid–liquid extraction is possible in non-aqueous systems: In a system consisting of a molten metal in contact with molten salts, metals can be extracted from one phase to the other. This is related to a mercury electrode where a metal can be reduced, the metal will often then dissolve in the mercury to form an amalgam that modifies its electrochemistry greatly. For example, it is possible for sodium cations to be reduced at a mercury cathode to form sodium amalgam, while at an inert electrode (such as platinum) the sodium cations are not reduced. Instead, water is reduced to hydrogen. A detergent or fine solid can be used to stabilize an emulsion, or third phase.
MEASURES OF EFFECTIVENESS
Distribution ratio
In solvent extraction, a distribution ratio is often quoted as a measure of how well-extracted a species is. The distribution ratio is equal to the concentration of a solute in the organic phase divided by its concentration in the aqueous phase. Depending on the system, the distribution ratio can be a function of temperature, the concentration of chemical species in the system, and a large number of other parameters.
Separation factor
The separation factor is one distribution ratio divided by another; it is a measure of the ability of the system to separate two solutes.
Decontamination factor
This is used to express the ability of a process to remove a contaminant from a product.
Slopes of graph
The easy way to work out the extraction mechanism is