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
Synthware™ Schlenk Flasks, Modified, with Glass Stopcock

Kjeldahl shape to facilitate heating and stirring

PYREX™ Distilling Flasks with Three Vertical, Level Necks, Standard Taper Joint
Side necks at same level as center neck
Heidolph™ Glassware - Evaporating Flasks

For use with Heidolph evaporators
PYREX™ Distilling Flasks
Round bottoms, vial mouths, with side arms at 75° angle
DWK Life Sciences Kimble™ KIMAX™ Brand 125mL Distilling Flask
Without stopper
Promotions are available
PYREX™ Distilling Flasks with Three Vertical Necks, Standard Taper Joint
With side and center neck standard taper joints
PYREX™ Distilling Flasks with Three Angle Necks, Standard Taper Joint
Provide maximum assembly and working space
DWK Life Sciences Kimble™ Kontes™ Distilling Three Neck Round Bottom Heavy Wall Flask
Side necks are angled
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Round Bottom Three Neck Heavy Wall Distilling Flasks
With outer joints
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Round Bottom Four Neck Heavy Wall Distilling Flasks
With vertical outer joints
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Distillation Flasks
Improved version of classic Schlenk tube
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Two Neck Round Bottom Heavy Wall Distilling Flasks
Outer joints. Side neck is angled.
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Three Neck Round Bottom Heavy Wall Distilling Flasks
With standard outer joints
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Round Bottom Five Neck Heavy Wall Distilling Flasks
With vertical outer joints
Promotions are available
PYREX™ Distilling Flasks with Four Necks, Standard Taper Joint
Four vertical necks with standard taper joints
PYREX™ Church Flask
For the distillation of bituminous materials suitable for road treatment
DWK Life Sciences Kimble™ KIMAX™ Chase KIMAX™ Pickel Extraction Flasks
Fit with metal condensers
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Distilling Two-Neck Round Bottom Heavy-Wall Flasks
Side neck is angled or vertical
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Mojonnier™ Fat Extraction Flask
For examination of dairy products
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Round Bottom Three Neck Indented Heavy Wall Distilling Flasks
Provides enhanced agitation when stirring
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Flasks with Three Angle Necks and standard taper Joints
Side necks are angled off center neck for greater accessibility
Promotions are available
DWK Life Sciences Kimble™ Kontes™ Round Bottom Three Neck Heavy Wall Jacketed Distilling Flasks
With all vertical outer joints
Promotions are available
BrandTech™ VITLAB™ PFA Round Bottom Flasks
Corrosion- and leach-resistant flasks excellent for rotary evaporation and distillation of high-purity chemicals
Synthware™ Schlenk Flasks, Modified, with High Vacuum Valve

Kjeldahl shape to facilitate heating and stirring
Synthware™ Schlenk Flasks, Modified, with PTFE Stopcock

Kjeldahl shape to facilitate heating and stirring
Synthware™ Reaction Tubes with Glass Stopcock

Cylindrical shaped tube with standard taper outer joint
United Scientific™ Borosilicate Glass Distilling Flask


Distilling Flasks ideal for distillation applications.
PYREX™ Distilling Flasks

Round bottoms, vial mouths, with side arms at 75° angle
Eisco™ Round Bottom 3 Parallel Necks Distilling Flask

High quality borosilicate 3.3 glass round bottom distilling flask with three parallel necks