Lecture bottle

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Lecture bottles are small compressed gas cylinders, used in laboratories as storage for small quantities of gasses or liquids with boiling point near or slightly below room temperature (standard conditions).

General

Lecture bottles are small metal cylinders, typically 300–450 mm long and 25–75 mm in diameter, made of steel, brass or nickel. A valve is connected at one end, from where the gas can be released.

Lecture bottles sometimes come together with a portable station, which is fitted with various pipes, tubes, valves and other controllers, which allow for better handling of the said mini-tanks.[1]

Most lecture bottles are not refillable.

Availability

Lecture bottles are sold by various chemical suppliers and industrial entities, though good quality ones are expensive and not easy to find, and most do not sell them to individuals.

Consumable small oxygen, propane/butane, helium cylinders can be found in many hardware and home-improvement stores. They are not refillable.

DIY lecture bottle

Small refillable metal cylinders can be reused to store non-corrosive gasses or liquids with low boiling point. However, if you intend to introduce a different gas than the original one, you will have to remove all traces of gas from the tank using vacuum. Non-refillable gas tanks are useless for storing gasses, though a skilled person can remove the valve from the tank and replace it with one that allows refilling.

NEVER REUSE OXYGEN CYLINDERS TO STORE FLAMMABLE GASSES! ALSO NEVER TRY TO CUT AN EMPTY OXYGEN TANK WITH A HOT TOOL OR FLAME!

Storing corrosive gasses inside OTC gas cylinders is frowned upon, as commercial tanks are not passivated and the corrosive reagent will slowly destroy the tank.

Uses

Lecture bottles are excellent for storing chemicals that boil close to room temperature, as metal cylinders are much stronger than glass bottles and are not brittle.

Safety

Lecture bottles used for storing corrosive reagents, such as hydrogen fluoride, hydrogen bromide, will slowly get corroded by the reagent they store. The reaction with the bottle wall produces hydrogen which causes the pressure inside the container to raise, which, coupled with the hydrogen embrittlement that may appear, may lead to an explosion.[2]

Lecture bottles used for storing corrosive reagents should be used in maximum one year of purchase.

See also

References

  1. https://www.sigmaaldrich.com/content/dam/sigma-aldrich/docs/Aldrich/Technical_Ads/al_gases_lecture_bottles.pdf
  2. http://www2.lbl.gov/ehs/Lessons/pdf/AHFcylinderLL.pdf

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