A
separatory funnel, also known as
separation funnel,
separating funnel, or colloquially
sep funnel, is a piece of laboratory glassware used in
liquid-liquid extractionLiquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid...
s to separate (
partition) the components of a mixture between two immiscible
solventA solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution.The most common solvent in everyday life is water. Most other commonly-used solvents are organic chemicals. These are called organic solvents...
phases of different
densitiesThe density of a material is defined as its mass per unit volume. The symbol of density is ρ .- Formula :Mathematically:where: is the density, is the mass, is the volume....
. Typically, one of the phases will be aqueous, and the other a non-polar
lipophilicLipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...
organic solvent such as
etherEther is a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...
, MTBE,
dichloromethaneDichloromethane is the organic compound with the formula CH
2Cl
2. This colorless, volatile liquid with a moderately sweet aroma is widely used as a solvent. More than 500,000 tons were produced in 1991. Although it is not miscible with water, it is miscible with many organic...
,
chloroformChloroform is the organic compound with formula CHCl
3. This colourless, sweet-smelling, dense liquid is a trihalomethane. It is also considered somewhat hazardous...
, or
ethyl acetateEthyl acetate is the organic compound with the formula CH3COOCH2CH3. This colorless liquid has a characteristic sweet smell like certain glues or nail polish removers, in which it is used...
.
A
separatory funnel, also known as
separation funnel,
separating funnel, or colloquially
sep funnel, is a piece of laboratory glassware used in
liquid-liquid extractionLiquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid...
s to separate (
partition) the components of a mixture between two immiscible
solventA solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution.The most common solvent in everyday life is water. Most other commonly-used solvents are organic chemicals. These are called organic solvents...
phases of different
densitiesThe density of a material is defined as its mass per unit volume. The symbol of density is ρ .- Formula :Mathematically:where: is the density, is the mass, is the volume....
. Typically, one of the phases will be aqueous, and the other a non-polar
lipophilicLipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...
organic solvent such as
etherEther is a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...
, MTBE,
dichloromethaneDichloromethane is the organic compound with the formula CH
2Cl
2. This colorless, volatile liquid with a moderately sweet aroma is widely used as a solvent. More than 500,000 tons were produced in 1991. Although it is not miscible with water, it is miscible with many organic...
,
chloroformChloroform is the organic compound with formula CHCl
3. This colourless, sweet-smelling, dense liquid is a trihalomethane. It is also considered somewhat hazardous...
, or
ethyl acetateEthyl acetate is the organic compound with the formula CH3COOCH2CH3. This colorless liquid has a characteristic sweet smell like certain glues or nail polish removers, in which it is used...
. Most organic solvents float on top of an aqueous phase, though important exceptions are most
halogenThe halogens or halogen elements are a series of nonmetal elements from Group 17 IUPAC Style of the periodic table, comprising fluorine, ; chlorine, ; bromine, ; iodine, ; and astatine,...
ated
solventA solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution.The most common solvent in everyday life is water. Most other commonly-used solvents are organic chemicals. These are called organic solvents...
s.
A separating funnel has the shape of a cone surmounted by a hemisphere. It has a stopper at the top and
stopcockA stopcock is a valve used to restrict or isolate the flow of a liquid or gas through a pipe.In Great Britain a stopcock, not to be confused with a gate valve or a DiCiaccio branch, is used to prevent flow of water into a domestic water system. There are usually two stopcocks for a home...
(tap), at the bottom. Separating funnels used in laboratories are typically made from
borosilicate glassBorosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are most well known for having very low coefficient of thermal expansion , making them resistant to thermal shock, more so than any other common glass.-History:Borosilicate...
and their stopcocks are made from glass or
PTFEIn chemistry, polytetrafluoroethylene is a synthetic fluoropolymer of tetrafluoroethylene which finds numerous applications. PTFE is most well known by the DuPont brand name Teflon....
. Typical sizes are between 50 mL and 3 L. In industrial chemistry they can be much bigger and for much larger volumes
centrifugeA centrifuge is a piece of equipment, generally driven by an electric motor , that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis...
s are used.
To use a separatory funnel, the two phases and the mixture to be separated in solution are added through the top with the stopcock at the bottom closed. The funnel is then closed and shaken very strongly to bring the phases into close contact. The funnel is then inverted and the tap carefully opened to release excess
vapor pressureVapor pressure or equilibrium vapor pressure is the pressure of a vapor in thermodynamic equilibrium with its condensed phases in a closed container. All liquids and solids have a tendency to evaporate into a gaseous form, and all gases have a tendency to condense back to their liquid or solid...
. The separating funnel is set aside to allow for the complete separation of the phases. The top and the bottom tap are then opened and the two phases are released by gravitation.
See also
- Laboratory funnel
- Multiphasic liquid
A multiphasic liquid, also known as a multiphasic liquid-liquid-liquid system, is a mixture consisting of more than two immiscible liquid phases. Biphasic mixtures consisting of two immiscible phases are very common and usually consist of an organic solvent and an aqueous phase...
for systems of more than three liquid phases
- Acid-base extraction
Acid-base extraction is a procedure using sequential liquid-liquid extractions to purify acids and bases from mixtures based on their chemical properties....
External links