The Teclu burner is an ambient air
laboratory
A laboratory (; ; colloquially lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. Laboratory services are provided in a variety of settings: physici ...
gas burner
A gas burner is a device that produces a controlled flame by mixing a fuel gas such as acetylene, natural gas, or propane with an oxidizer such as the ambient air or supplied oxygen, and allowing for ignition and combustion.
The flame is ge ...
, that was created by Romanian chemist
Nicolae Teclu
Nicolae Teclu (); (11 October 1839, Kronstadt, Austrian Empire (today Brașov, Romania) – 13 July 1916, Vienna, Austria-Hungary) was a Romanian chemist, who gave his name to the worldwide-used " Teclu burner". He studied engineering and ar ...
in 1882. The burner is most commonly used to heat substances in a laboratory, can be used for sterilisation and sometimes it is used for soldering or glasswork.
It is commonly made from brass or iron.
The burner physically consists of a round base, a tube connected to it providing the gas to the flame and a vertical metal tube that directs the flame upwards. The tube has a conical shape closer to the base.
The burner was created on the basis of Nicolae Teclu's previous studies on flame
spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter ...
and specifically, his experiments including flames positioned at different levels in a tube. Teclu was able to conclude that changing the position of the flame in a vertical tube can effect the splitting of the flame and optimize the heat produced by the flame. As a result of this alteration, this burner compared with the
Bunsen burner
A Bunsen burner, named after Robert Bunsen, is a kind of ambient air gas burner used as laboratory equipment; it produces a single open gas flame, and is used for heating, sterilization, and combustion.
The gas can be natural gas (which is ma ...
is able to produce higher flame temperatures: around .
The research behind the creation of this burner was first published in 1892. There are some early Teclu burners on display in the Virtual Gas Museum in Poland
and also in the Science Museum, London.
Physical components and uses
The Teclu burner is a gas burner that is used most often as piece of laboratory equipment for experimental and educational purposes. The Teclu Burner is most commonly used for rapidly heating substances using an open flame. While the Teclu burner's primary function is to serve as a piece of equipment that is used in a laboratory, the Teclu burner can also be used for glasswork and even used for
soldering
Soldering (; ) is a process in which two or more items are joined by melting and putting a filler metal ( solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Unlike welding, soldering does not in ...
.
The Teclu Burner can produce a very hot flame of around . It is commonly made out of brass or iron.
The burner consists on a round base, a tube connected to it providing the flame with gas and a vertical metal tube that directs the flame upwards. The tube has a conical shape closer to the base. The tube dimensions range between in height and in diameter.
It is designed with a screwed air valve which can be tightened or loosened for gas regulation.
The structure of this device is more simple than other burners,
because in the Teclu burner the inner flame is able to be lifted and placed on top of the tube, with its tip pointing upward. This allows for a single flame to be produced out of the tube.
History and creation

The inventor of the Teclu burner is the Romanian chemist Nicolae Teclu. Teclu is most commonly known for his studies of flames. Teclu was born in
Braşov, Romania on 7 October 1839 and graduated from high school in Vienna. After graduation with a Bachelor of Science in
Munich
Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the third-largest city in Germany, after Berlin and Ha ...
, he returned to Vienna and attended chemistry classes at the Acedemy of Fine Arts in
Vienna
en, Viennese
, iso_code = AT-9
, registration_plate = W
, postal_code_type = Postal code
, postal_code =
, timezone = CET
, utc_offset = +1
, timezone_DST ...
. He began his career as a young scientist and assisted Professor
Ernest Ludwig
Ernest is a given name derived from Germanic word ''ernst'', meaning "serious". Notable people and fictional characters with the name include:
People
*Archduke Ernest of Austria (1553–1595), son of Maximilian II, Holy Roman Emperor
*Ernest, ...
. Soon after, he became Professor of Chemistry at the Technical Chemistry Department of the
Vienna Trade Academy
en, Viennese
, iso_code = AT-9
, registration_plate = W
, postal_code_type = Postal code
, postal_code =
, timezone = CET
, utc_offset = +1
, timezone_DST ...
. He also presented academic lectures on the chemistry of colours at the Academy of Fine Arts. Other notable investigations Teclu was involved in were the burning process of combustible gases, the analysis of natural products and also studies on the composition of paper.
Teclu was also constantly occupied with creating and investigating new and more advanced laboratory equipment.
The Teclu Burner was created on the basis Teclu's studies and tests investigating the combustion rate of a gaseous mixture in regards to its oxygen content. Teclu conducted an experiment where he compared the flames that were produced when moving the position of a flame in a vertical tube.
From this experiment he came to the conclusion that a flame is split into different parts while it is burning- one flame burning on the inside of the tube and one flame burning on the outside of the tube. He described the flame on the inside as very hot, with a green hue that points in a downward direction and is being supplied oxygen that is contained in the gaseous mixture. He noted that the flame on the outside has a blue hue, points in an upward direction and is supplied with oxygen from its surroundings. Using this conclusion and his prior knowledge and research on flames, Teclu successfully created a burner in 1882 where the flame in the tube was able to be lowered or lifted to create a very hot flame.

The first publication of his research behind the creation of the Teclu burner was 10 years later, in 1892 and the publication was titled “Ein neuer Laboratoriums Brenner". This article was issued in the
Für Praktische Chemie Journal. The original burner was patented by a company owned by W. J. Rohrbeck Nachfolger which was based in Vienna and a company owned by Franz Hugershoff which was based in
Leipzig
Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as ...
.
A Teclu Burner that was manufactured in the 1960’s is currently on display in the Gasworks Museum in Paczkow, Poland. It is made from cast iron and brass and it was admitted to the museum in 1998.
Other early makes of the Teclu burner are displayed in the Science Museum in London. Here there are two models of the Teclu burner displayed, one whole and one that has been cross sectioned to examine the inside parts of the burner.
Examples of the Teclu Burner in past experiments
The Teclu Burner can be helpful in experiments where moisture sensitive compounds are being used. An example where the Teclu burner was used in an experiment was during the preparation of glassware for the handling of
beryllium
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form m ...
compounds. Beryillum is moisture sensitive and so it is necessary to exclude the presence of water that might be still left on the surface of the glassware after cleaning them. The experiment conductors stored the glassware for at least four hours in a heated cabinet, which was kept at . Then the glassware removed and connected to a
Schlenk line
The Schlenk line (also vacuum gas manifold) is a commonly used chemistry apparatus developed by Wilhelm Schlenk. It consists of a dual manifold with several ports. One manifold is connected to a source of purified inert gas, while the other is c ...
. The glassware was heated with a Teclu burner under vacuum up until the flame of the burner turned to a yellow/orange colour. At this point the glassware was hot enough and was then cooled to room temperature while still being under vacuum. This procedure was be repeated several times, to ensure no moisture was left on the glassware. Using a Teclu burner instead of a heat gun will ensure that you have obtained the lowest possible moisture levels in glass laboratory equipment and this should be sufficient enough for the moisture sensitive substances to not react when added into the glassware.
The Teclu burner was used in an experiment investigating the effect of the process on the
crucible swelling number of coal (CSN). The number is a measure of the degree of swelling of the sample. A sample of 1g of freshly ground minus 72 "B.S. mesh coal" was heated using a Teclu burner to approximately for 1.5 minutes and to in the next minute. The final result was recorded and coal with a profile of 8 to 9 would be considered high coal quality.
The Teclu burner was also used in an experiment which aimed to investigate the spark formation from rare earth elements. The powders containing the rare earth elements were passed into the centre of the gas flame produced by the Teclu burner and the sparks were then examined. The Teclu burner was operated with methane through an aluminium tube from a distance of . These sparks were then examined using time-resolved emission spectroscopy, long-time exposures, and NIR (
Near-infrared spectroscopy
Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 nm to 2500 nm). Typical applications include medical and physiological diagnostics and research inc ...
)/ MIR (mid-
Infrared spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or function ...
) imaging.
Similarities and differences to other notable burners
The Teclu burner vs. the
Bunsen burner
A Bunsen burner, named after Robert Bunsen, is a kind of ambient air gas burner used as laboratory equipment; it produces a single open gas flame, and is used for heating, sterilization, and combustion.
The gas can be natural gas (which is ma ...
:
The Teclu Burner was invented in 1882 as opposed to the Bunsen Burner invented in 1855. The respective developers Nicolae Teclu, a Romanian
chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe ...
, and Robert Bunsen, a German chemist, also differed in their educational backgrounds as Teclu specialised in engineering, architecture, and chemistry while Bunsen primarily studied chemistry, mineralogy, and mathematics. The devices themselves differ in their abilities to accurately control the amounts of methane gas and air inputted into the tube therefore contributing to a hotter flame able to be achieved by the Teclu Burner.
While the Bunsen burner has open slots on the side of the tube, the Teclu Burner regulates the air and gas input through the distance between the screw below the base of the tube and the end of the tube itself. This change in design also allows for greater mixing of methane gas and air which in turn produces higher temperatures as seen in the Teclu Burner. More specifically, the Teclu Burner can reach approximately while the Bunsen Burner achieves only . Both the Bunsen and Teclu burner burn with noise.

The Teclu burner vs. the
Meker burner:
The Meker Burner differs in that it is designed with more openings in the lower part of the tube than the Teclu Burner and has a wire grid covering the top of the tube allowing the flame to be divided into smaller flames.
This allows for temperatures to reach and this allows the device to burn without noise unlike the Teclu and Bunsen burners. The Meker Burner has a wider tube than the Teclu Burner.
The Teclu burner vs. the Tirril Burner:
The Tirril burner has a
needle valve
A needle valve is a type of valve with a small port and a threaded, needle-shaped plunger. It allows precise regulation of flow, although it is generally only capable of relatively low flow rates.
Construction and operation
An instrument n ...
to regulate the gas intake directly unlike the Teclu burner which regulates gas directly from the gas source. Additionally, the Tirrill Burner differs in that it reaches around and the Teclu burner reaches .
The Teclu burner vs. the Amal burner:
The Amal burner is a burner created by the modification of the Bunsen and Teclu burner. The Amal burner was marketed by Messrs. Amal Ltd., of Birmingham. In this burner, there is a needle valve which can sensitively control of gas the flow into the burner. It is inserted in the orifice of the jet and can be adjusted by an external screw. The flame produced can be reduced near to invisibility, by using this needle-valve. This burner's combustion-head is perforated with many small holes, so that the flame the burner produces consists of many aerated small cones whereas in the Teclu burner, only one single flame is produced. There is an insulated hooked strip of metal attached to the base that functions as a holder for when the burner itself becomes too hot to handle. The Amal burner is usually 5 inches high and its tube has approximately a 1 inch diameter.
References
External links
*
Teclu burner dating from 1900 in the Science Museum, LondonTeclu burner dating from 1913 in the Science Museum, LondonTeclu burner dating from 1914 in the Science Museum, London- this exhibit has been sectioned to show the internal structure.
{{Laboratory equipment
Burners
Laboratory equipment
Romanian inventions