A separating funnel, also known as separation funnel, separatory funnel, or colloquially sep funnel, is a laboratory glassware used in liquid-liquid extractions to separate (partition) the components of a mixture between two immiscible solvent phases of different densities. Liquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two Miscibility is a term commonly used in Chemistry that refers to the property of Liquids to mix in all proportions forming a Homogeneous Solution A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different
Typically, one of the phases will be aqueous, and the other a non-polar lipophilic organic solvent such as ether, MTBE, dichloromethane, chloroform, or ethyl acetate. Lipophilicity, fat-liking, refers to the ability of a Chemical compound to dissolve in fats oils lipids and non-polar solvents such as Hexane or A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Ether is a class of Organic compounds which contain an ether group — an Oxygen Atom connected to two (substituted Alkyl Methyl tert -butyl ether, also known as methyl tertiary butyl ether and MTBE, is a Chemical compound with molecular formula C5H12O Dichloromethane ( DCM) or methylene chloride is the Chemical compound with the formula CH2Cl2 Chloroform, also known as trichloromethane and methyl trichloride, is a Chemical compound with formula C[[Hydrogen H]] Cl Ethyl acetate ( systematically, ethyl ethanoate commonly abbreviated EtOAc or EA is the Organic compound with the formula CH3COOCH2CH3 Most organic solvents stay on top of an aqueous phase, important exceptions are most halogenated solvents. Abundance Owing to their high Reactivity, the halogens are found in the environment only in compounds or as Ions Halide ions and oxoanions
A separating funnel has the shape of a cone surmounted by a hemisphere. It has a stopper at the top and stopcock (tap), at the bottom. A stopcock is a Valve used to restrict or isolate the flow of a liquid or gas through a pipe. Separating funnels used in the lab are typically made from borosilicate glass and the stopcocks are made from glass or Teflon. Borosilicate glass is a type of Glass with the main glass-forming constituents Silica and Boron oxide. Teflon is a Registered trademark and Brand name of the DuPont company for products made from three types of fluorine-containing polymers ( Fluoropolymers Typical sizes are between 50 mL and 3 L. In industrial chemistry they can be much bigger and for much larger volumes centrifuges are used. A centrifuge is a piece of equipment generally driven by a motor that puts an object in Rotation around a fixed axis, applying a force perpendicular to the axis
To use the 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 pressure. Vapor pressure (also known as equilibrium vapor pressure or saturation vapor pressure) is the Pressure of a Vapor in equilibrium 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 for systems of more than three liquid phases
- Acid-base extraction
External links
- MIT OpenCourseWare Digital Lab Techniques Manual Separatory funnel demonstration video, see "Reaction Work-Up I"