Distilling Flasks
Distilling Flasks
Distilling flasks are used to separate mixtures of two liquids with different boiling points. A variety of designs and capacities are available to accommodate distillation processes of varying complexities. Flask design typically features a distillation column in the form of a long neck, a side arm that facilitates condensation, and a round bottom for uniform heat distribution. For complex distillations, flasks with two or more necks that allow for connection to multiple components are available. Neck joints come in a variety of sizes, orientations, and joint types. Distilling flasks are manufactured from heat and chemical resistant materials, such as borosilicate glass or PFA.
Distilling flasks, also known as distillation flasks, are types of laboratory flasks forming part of larger distillation assemblies used for the separation and/or purification of liquids or liquid mixtures where the components have different boiling points. Distillation flasks are used to contain and heat the liquid(s) that require purification. They are round-bottomed for uniform heat distribution, with a stoppered or jointed neck of variable length, to which is attached a downward-sloping, inclined side-arm for connection to a condensing unit or similar component to cool the heated vapors back down to their liquid state. For complex distillations, flasks with two or more necks that allow for connection to multiple components are available.
Distilling flasks are usually made of a high-quality glass, such as borosilicate, for heat and chemical resistance and for reusability. Heating mantles are the preferred heat source for improved temperature control and for safety reasons, but direct flame heat sources are also used. Immersion thermometers can also be introduced into the neck of the flasks to monitor the temperature of the distillation process.
Distilling flasks are available in a range of capacities, and the neck joints come in a variety of sizes, orientations, and joint types.
What are distillation flasks used for?
- Separation and purification of miscible liquid mixtures in organic chemistry
- Drying off solid residues and/or solvent removal
- Distilling off liquids from polymers and petroleum products
- Removal of particulates or other solid contaminants
- As part of a water purification system for production of distilled water for laboratory use
GPE Scientific™ J Young Sample Flask, Cylindrical with Fine Thread Tap
GPE Scientific™ J Young Sample Flask, Cylindrical with Fine Thread Tap is specially designed for use with vacuum manifolds and Schlenk lines.

Pyrex™ Borosilicate Glass Distillation Flasks
Complies with many ASTM test method requirements. Pyrex™ Borosilicate Glass Distillation Flasks require use of a calibrated thermomenter for 76mm immersion.
Pyrex™ Borosilicate Glass Distillation Flasks
Complies with many ASTM test method requirements. Pyrex™ Borosilicate Glass Distillation Flasks require use of a calibrated thermomenter for 76mm immersion.
Lenz Laborglasintrumente Three-Neck Round-Bottom Flasks, Side Necks Angled
Made of high quality materials. Each manufacturing step is tested through an extensive quality management system, based on DIN ISO 9001/EN 29001.
Lenz Laborglasintrumente Two-Neck Round-Bottom Flasks, Side Neck Parallel
Made of high quality materials. Each manufacturing step is tested through an extensive quality management system, based on DIN ISO 9001/EN 29001.
DWK Life Sciences DURAN™ Engler Flask, with beaded rim, side outlet
Engler Distilling Flasks is used for the atmospheric distillation of petroleum products.
Lenz Laborglasintrumente Three-Neck Round-Bottom Flasks
Made of high quality materials. Each manufacturing step is tested through an extensive quality management system, based on DIN ISO 9001/EN 29001.
Lenz Laborglasinstrumente™ Two-Neck Round-Bottom Flasks, Side Neck Angled
Made of high quality materials. Each manufacturing step is tested through an extensive quality management system, based on DIN ISO 9001/EN 29001.
GPE Scientific™ J Young Schlenk Flask, Cylindrical with Fine Thread Tap and Cone
GPE Scientific™ J Young Schlenk Flask, Cylindrical with Fine Thread Tap and Cone is specially designed for use with vacuum manifolds and Schlenk lines.
BrandTech™ VITLAB™ PFA Round Bottom Flasks
Take advantage of PFA, which is especially suitable for use in trace analysis, with Vitlab™ PFA Round Bottom Flasks. They have high thermal stability, from -200 °C to +260 °C, and are autoclavable.
GPE Scientific™ J Young Schlenk Flask, Round Bottom with Glass Key and Socket
GPE Scientific™ J Young Schlenk Flask, Round Bottom with Glass Key and Socket is specially designed for use with Schlenk lines and vacuum manifolds, and is available in different capacities.
GPE Scientific™ J Young Sample Flask with O-Ring Tap and Cold Finger Plain Arm
GPE Scientific™ J Young Sample Flask with O-Ring Tap and Cold Finger Plain Arm is designed for use with Schlenk lines and a vacuum manifold and available in various capacities.
GPE Scientific™ J Young Vacuum/Schlenk Flask with O-Ring Tap and Plain Arm
GPE Scientific™ J Young Vacuum/Schlenk Flask with O-Ring Tap and Plain Arm is designed for use with Schlenk lines and a vacuum manifold and available in various capacities.
GPE Scientific™ J Young Vac Line Bubbler
GPE Scientific™ J Young Vac Line Bubbler is specially designed for use with Schlenk lines and vacuum manifolds.
GPE Scientific™ Schlenk Flask, Cylindrical with Glass Tap and Cone
GPE Scientific™ Schlenk Flask, Cylindrical with Glass Tap and Cone are specially designed for use with Schlenk lines and vacuum manifolds and are available in different capacities.
DWK Life Sciences Kimble™ Kontes™ Mojonnier™ Fat Extraction Flask
For examination of dairy products
GPE Scientific™ J Young Vacuum/Schlenk Flask with O-Ring Tap and O-Ring Ball Joint Cup
GPE Scientific™ J Young Vacuum/Schlenk Flask with O-Ring Tap and O-Ring Ball Joint Cup is designed for use with Schlenk lines and a vacuum manifold and available in various capacities.
GPE Scientific™ J Young Sample Flask, Cylindrical with Fine Thread Tap and B14 Socket
GPE Scientific™ J Young Sample Flask, Cylindrical with Fine Thread Tap and B14 Socket is specially designed for use with vacuum manifolds and Schlenk lines.
GPE Scientific™ J Young Schlenk Flask, Round Bottom with Fine Thread Tap and Socket
GPE Scientific™ J Young Schlenk Flask, Round Bottom with Fine Thread Tap and Socket is specially designed for use with Schlenk lines and vacuum manifolds.
DWK Life Sciences Kimble™ Kontes™ Flasks with Three Angle Necks and standard taper Joints
Side necks are angled off center neck for greater accessibility
DWK Life Sciences DURAN™ Blank for Engler Distilling Flask, with beaded rim
For further processing.
Pyrex™ Quickfit™ Pear Shaped Distillation Flask
Designed for micro and semi-micro distillations