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Carl Auer von Welsbach

Carl Auer von Welsbach

Born 1 September 1858

Vienna, Austrian Empire

Died 4 August 1929 (aged 70)

Mölbling, Austria

Nationality Austrian

Fields chemistry

Doctoral advisor Robert Bunsen

Known for rare earth elements

Notable awards Elliott Cresson Medal (1900)

From Wikipedia, the free encyclopedia

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Carl Auer Freiherr von Welsbach (1

September 1858 – 4 August 1929) was an

Austrian scientist and inventor who had a

talent for not only discovering advances, but

turning them into commercially successful

products. He is particularly well known for his

work on rare earth elements, which led to the

development of the flint used in

modernlighters, the gas mantle which brought

light to the streets of Europe in the late 19th

century, and the development of the metal

filamentlight bulb.

Contents [hide]

1 Early life

2 Rare earths

3 Gas mantle

4 Lighting flint

5 Death

6 Commemoration

7 See also

8 References

9 Further reading

10 External links

Early life [edit]

Auer von Welsbach was born in Vienna on 1 September 1858 to Therese and Alois Auer.

Alois, ennobled in 1860, was director of the Imperial printing office (K.-k . Hof- und

Staatsdruckerei) in the days of the Austrian Empire. Carl went to secondary school

inMariahilf and Josefstadt before graduating in 1877, and joining the Austro-Hungarian

Armyas a Second Lieutenant.

In 1878 von Welsbach entered the University of Vienna, studying mathematics,

generalchemistry, engineering physics, and thermodynamics. He then moved to

the University of Heidelberg in 1880, where he continued his studies in chemistry under the

direction ofRobert Bunsen (inventor of the Bunsen burner). He received his Ph.D. in 1882,

and returned to Vienna to work as an unpaid assistant in Prof. Adolf Lieben's laboratory,

working with chemical separation methods for investigations on rare earth elements.

Rare earths [edit]

In 1885 von Welsbach used a method he developed himself to separate didymium for the

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first time. He saw several different colored versions which he named "praseodymium"

(green) and "neodidymium" (pink); the latter then became the more common name for the

element, neodymium.

Gas mantle [edit]

Later that year von Welsbach received a patent on his development of the gas mantle,

which he called Auerlicht, using a chemical mixture of 60% magnesium oxide,

20%lanthanum oxide and 20% yttrium oxide which he called Actinophor. To produce a

mantle,guncotton is impregnated with a mixture of Actinophor and then heated, the cotton

eventually burns away leaving a solid (albeit fragile) ash which glows brightly when heated.

These original mantles gave off a green-tinted light and were not very successful, and his

first company formed to sell them failed in 1889.

In 1890 he introduced a new form of the mantle based on a mixture of 99% thorium

dioxideand 1% cerium(IV) oxide which he developed in collaboration with his colleague Dr.

Haittinger. These proved both more robust as well as having a much "whiter" light. Another

company founded to produce the newer design was formed in 1891, working with fellow

student from the university Ignaz Kreidl, and the device quickly spread throughout Europe.

He then started work on development of metal-filament mantles, first with platinum wiring,

and then osmium. Osmium is very difficult to work with, but he developed a new method

which mixed osmium oxide powder with rubber or sugar into a paste, which is then

squeezed through a nozzle and fired. The paste burns away, leaving a fine wire of osmium.

Although originally intended to be a new mantle, it was during this period

that electricitywas being introduced into the market, and he started experimenting with

ways to use the filaments as a replacement for the electric arc light. He worked on this

until finally developing a workable technique in 1898, and started a new factory to produce

his Auer-Oslight, which he introduced commercially in 1902. The metal filament light

bulb was a huge improvement on the existing carbon filament designs, lasting much

longer, using about 1/2 the electricity for the same amount of light, and being much more

robust.

Lighting flint [edit]

In 1903 von Welsbach won another patent for a fire striker ("flint") composition

namedferrocerium. Welsbach's flints consisted of pyrophoric alloys, 70% cerium and

30% iron, which when scratched or struck would give off sparks. This system remains in

wide use incigarette lighters today. In 1907 he formed Treibacher Chemische Werke

GesmbH to build and market the devices. In 1920 he received the Siemens-Ring as his

name had become a synonym for the rise of artificial lightning.

Over the rest of his life he turned again to "pure" chemistry and published a number of

papers on chemical separation and spectroscopy. He presented a major paper on his work

on the separation of radioactive elements in 1922.

Death [edit]

Von Welsbach died on 4 August 1929.[1]

Commemoration [edit]

In 2008 (150 years of his birth) von Welsbach was selected as a main motif for a high value

collectors' coin: the Austrian €25 Fascination Light. The reverse has a partial portrait of

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Fascination Light commemorative coin

Welsbach on the left hand side. The sun shines

in the middle of the green niobium pill, while

several methods of illumination from the gas

light from incandescent light bulbs and neon

lamps to modern Light-emitting diodes spread

out around the silver ring.