Friedrich Oskar Giesel
Encyclopedia
Friedrich Oskar Giesel was a German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 organic chemist
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...

. During his work in a quinine
Quinine
Quinine is a natural white crystalline alkaloid having antipyretic , antimalarial, analgesic , anti-inflammatory properties and a bitter taste. It is a stereoisomer of quinidine which, unlike quinine, is an anti-arrhythmic...

 factory in the late 1890s he started to work on the at-that-time-new field of radiochemistry
Radiochemistry
Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes...

 and started the production of radium. In the period between 1902 and 1904 he was able to isolate a new element emanium. In a now controversially reviewed process it was stated that emanium is identical to actinium
Actinium
Actinium is a radioactive chemical element with the symbol Ac and atomic number 89, which was discovered in 1899. It was the first non-primordial radioactive element to be isolated. Polonium, radium and radon were observed before actinium, but they were not isolated until 1902...

, which was discovered by André-Louis Debierne
André-Louis Debierne
André-Louis Debierne was a French chemist and is considered the discoverer of the element actinium....

 in 1899.

Life and work

After studying in Berlin with Carl Liebermann he received his Ph.D at the University of Göttingen. Giesel worked at the Chininfabrik Braunschweig. Besides his work in the factory, Giesel's focus was on radiochemistry. Shortly after publication of the discovery of polonium
Polonium
Polonium is a chemical element with the symbol Po and atomic number 84, discovered in 1898 by Marie Skłodowska-Curie and Pierre Curie. A rare and highly radioactive element, polonium is chemically similar to bismuth and tellurium, and it occurs in uranium ores. Polonium has been studied for...

 in the summer of 1898, he started to isolate the new element from the waste of uranium production in the chemical plant E. de Haën
Eugen de Haën
Eugen de Haën was a German chemist and founder of the chemistry factory E. de Haën. After studying in Heidelberg under the supervision of Kirchhoff and Bunsen, de Haën worked in several chemical factories. In 1861 he founded the E. de Haën company in Linden and later in List, two small...

 in Hanover
Hanover
Hanover or Hannover, on the river Leine, is the capital of the federal state of Lower Saxony , Germany and was once by personal union the family seat of the Hanoverian Kings of Great Britain, under their title as the dukes of Brunswick-Lüneburg...

. By March 1899 he could present the first radium to the chemical society of Braunschweig and by mid-1899 he published his results on radium. Giesel improved the separation of radium from barium by using the bromide
Bromide
A bromide is a chemical compound containing bromide ion, that is bromine atom with effective charge of −1. The class name can include ionic compounds such as caesium bromide or covalent compounds such as sulfur dibromide.-Natural occurrence:...

s instead of the chloride
Chloride
The chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...

s for the fractional crystallization
Fractional crystallization (chemistry)
In chemistry, fractional crystallization is a method of refining substances based on differences in solubility. If a mixture of two or more substances in solution is allowed to crystallize, for example by allowing the temperature of the solution to decrease, the precipitate will contain more of...

. He produced large quantities of pure radium and polonium for commercial applications from uranium ore. Even William Ramsay
William Ramsay
Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...

 and Frederick Soddy
Frederick Soddy
Frederick Soddy was an English radiochemist who explained, with Ernest Rutherford, that radioactivity is due to the transmutation of elements, now known to involve nuclear reactions. He also proved the existence of isotopes of certain radioactive elements...

 were buying radium from the factory of Giesel.
The use of Sidot's blende (zinc sulfide) instead of barium platinocyanide as a luminescence material to make the radioactive rays visible was a commonly accepted improvement. He did several self-experiments with radioactive substances and was able to affirm the damaging effects of radioactive radiation on skin. Because of prolonged contact with radioactive material, fingers of his right hand had to be amputated and he suffered from lung cancer. He died of lung cancer in 1927.

The discovery of emanium

Giesel isolated from pitchblende
Uraninite
Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements...

 a lanthanum
Lanthanum
Lanthanum is a chemical element with the symbol La and atomic number 57.Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series. It is found in some rare-earth minerals, usually in combination with cerium and...

-containing fraction which showed unique properties. He produced several compounds of the new element, and after studying for two years he was confident enough to give the new element the name emanium. He was aware of the discovery of actinium by André-Louis Debierne
André-Louis Debierne
André-Louis Debierne was a French chemist and is considered the discoverer of the element actinium....

. In publications from 1899 and 1890 Debierne does not give the exact procedures to obtain actinium, but from the description of chemical properties which he described as similar to titanium (1899) or similar to thorium (1890) it was clear for Giesel that the two elements must be different. A later comparison of the two elements by Otto Hahn
Otto Hahn
Otto Hahn FRS was a German chemist and Nobel laureate, a pioneer in the fields of radioactivity and radiochemistry. He is regarded as "the father of nuclear chemistry". Hahn was a courageous opposer of Jewish persecution by the Nazis and after World War II he became a passionate campaigner...

, Otto Sackur
Otto Sackur
Otto Sackur was a German physical chemist.He is known for the development of the Sackur-Tetrode equation which he developed independently of Hugo Tetrode...

 and others showed that the two elements were identical. Debierne's name was retained because it had seniority.

Giesel stated in one of his publications that the sample Debierne provided for the comparison was a lanthanum fraction obtained by the same process he used and not the titanium or thorium fractions from earlier publications. This fact never led to an open controversy but the history of the discovery stayed questionable, and publications from 1971 and later in 2000 showed that the claims of André-Louis Debierne in 1904 conflict with the publications in 1899 and 1890, making Giesel the real discoverer of actinium.

See also

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