Johann Wolfgang Döbereiner

Johann Wolfgang Dobereiner ( born December 13, 1780 in Hof, † March 24, 1849 in Jena ) was a German chemist who is considered as a pioneer in the development of the periodic table and with the investigation of platinum paved the way for catalysis.

Life

The son of a coachman Johann Wolfgang Dobereiner grew up in poverty on a manor in the bow with white village and received only moderate education. He began 1794 in Munchberg an apprenticeship as a pharmacist followed the five years of wandering. He worked in pharmacies in Dillenburg, Karlsruhe and Strasbourg, and was suitable way autodidactic knowledge of chemistry, botany and mineralogy at.

In 1802 he returned, did not make it, however, to become self-employed as pharmacist.

Called attention to himself by Dobereiner studies of practical chemical problems. So he finally received in 1810 by Duke Carl August of Saxe- Weimar as an associate professor of Chemistry, Pharmacy and Technology at the University of Jena.

Since he could boast no academic degree, given the title of Dr. phil was. granted, as his previous publications " were already wearing the unmistakable stamp of genius and perfection in itself. "

For the faculty, the selection of Dobereiner was a stroke of luck, because in his person combined genius as a researcher, a very strong interest in technical processes and an excellent teaching certificate.

His lectures were very practical characterized by many experiments on inorganic and organic chemistry. In addition, there were numerous trips to chemical plants in the area of Jena to show his students Chemical Technology and pneumatic chemistry in practice. One of his later also highly successful students was Rudolf Christian Böttger, inventor of safety matches and developers of the electroforming.

As a chemistry advisor of Duke Carl August, he dealt with the improvement of manufacturing processes and the structure of various companies which could be used profitably. He was asked for an expertise of Bad Berka mineral sources contributed to the construction of a sulfuric acid plant, and developed methods for the recovery and recycling of indigo instead of Färberwaids.

Furthermore, a factory was the time of the Continental System under Döbereiner participation in Tiefurt built for sugar production from starch and also the production of acetic acid by the quick vinegar process by oxidation of alcohol is mentioned. In addition there are distilleries and breweries.

Around 1818, he undertook, at the suggestion of Goethe and the Grand Duke attempts for generating gas for lighting purposes, but he found that " coal and water result from their interaction in high temperature, the wohlfeilste and purest fire gas. " In the same year 1818, he was elected a member of the Leopoldina.

In 1828 he led melting experiments for the production of Celestine - Barytglas and also studied fermentation processes.

He made his most important and famous discoveries in the field of catalytic action of platinum metals and in the detection of similarities in the properties of the known elements.

Less well known is Dobereiner as a pioneer of chemical internships in teaching at German universities. Even before Justus von Liebig in Giessen Dobereiner 1820 held in Jena from a chemically - practical conference, to be enjoyed by the students great popularity. Goethe supported this by purchasing a house in Jena, and the procurement of laboratory equipment. Dobereiner is out of gratitude, despite financial problems remained loyal to the University of Jena, although he had received honorable callings to other universities.

He died on 24 March 1849 in Jena and was buried at St. John's Cemetery at Philosopher's Walk. The inscription on his grave stone reads: Goethe's consultant, creator of the Triad teaching, discoverer of platinum catalysis.

Discoveries

Triad rule

Dobereiner is considered as a thought leader for the development of the periodic table of the elements. In 1816 he discovered a connection between the elements calcium, strontium and barium. They had very similar properties and the atomic mass of the middle element was just the average of the atomic masses of other two elements.

This finding was published in 1829 in his work to attempt a grouping of elementary substances according to their analogy. Dobereiner arranged while 30 of the past 53 known elements in groups of three, the " triad " of.

By Triad rule predictions about as yet unknown elements could be made ​​. So Dobereiner said the atomic weight of bromine before.

The Döbereiner'sche triad usually formed an important basis for the developed around 1870 periodic table of elements (also see development of the periodic table of elements).

Catalysis and Dobereiner Lighter

A large part of his research made ​​from the study of the catalytic effect of the platinum metals. Already in 1816 he succeeded with the help of platinum black, the oxidation of ethanol to acetic acid. A few years later he succeeded to the ignition of a hydrogen-oxygen mixture under the influence of platinum sponge one of the most important discoveries of the early catalysis chemistry. It led to the invention of the Döbereinerschen platinum lighter, which has become a coveted object of trade.

With the observation that oxyhydrogen could be detonated by means of an iridium - osmium mixture, Dobereiner discovered in 1824 the principle of mixed catalysts used later in the large scale chemical industry.

Function of Dobereiner Lighter

In a glass vessel contains diluted sulfuric acid and in fact plunging bell jar, a piece of zinc. At the upper end of the bell jar is closed by a valve; Upon opening of this by operating a lever, the gas flows into the bell jar through a nozzle to the outside, the acid rising to and reacts with the zinc, the hydrogen gas H2 is formed. This flows through the nozzle to a " platinum sponge " ( finely divided platinum ). This catalyzes the reaction of hydrogen with oxygen 2H2 O2 → 2H2O ( oxyhydrogen reaction ); by the simultaneously released heat (exothermic reaction), the gas mixture is ignited.

If the lever is released, the valve is closed again, the hydrogen gas can not escape upwards, pushing the acid from the glass dome back into the reservoir.

Honors

In the courtyard Döbereinerstraße is named after him. In his honor, wearing a lecture hall of Chemistry and Geoscience Faculty of the University of Jena the name Dobereiner Auditorium, which is located a few hundred meters from its grave -. From 20 to 22 May 1980 in the Friedrich -Schiller- University Jena an "International Dobereiner Colloquium " held on the occasion of his 200th birthday.

The asteroid ( 32853 ) Dobereiner was named after the 27 April 2002.

Literature

• Schwedt, Georg: Goethe as a chemist, Berlin and Heidelberg, 1998, p.141 -62 and 350-51.
• Dobereiner International Colloquium on the occasion of the 200th birthday of Johann Wolfgang Dobereiner from 20 to 22 May 1980, Jena / Friedrich -Schiller- University of Jena; [Ed: Franz Bolck. Responsible Edit: Günther Heublein, Eberhard Müller ... ]. Otherwise. People: Bolck, Franz * 1918 - *; Heublein, Günther [Edit ]; Müller, Eberhard [Edit ] body: International Colloquium Dobereiner < 1980 Jena >. University . Released: Jena: .. Friedrich -Schiller- University, 1981 174 pp. with portrait.
• Grand Ducal School of Chemistry. From JWDöbereiner, in: Historical and topographical POCKET OF JENA and its environment, Edited. by Jonathan Carl Zenker, composed of Messrs. Brehm, Dobereiner et al. Jena: Frommann, 1836 Section III.4, pp. 63-64. .. online
• The chemist Dobereiner and his minister Goethe - A desk study. By Heinrich Arnold, in: Vital principle Academy, Festschrift for 450th anniversary of the University of Jena, [Ed Werner Köhler et al ] Erfurt. Akad Wiss -profit, special fonts 38/2008, pp. 211-232. . - ISBN 978-3-932295-72-0. URL
• Correspondence between Goethe and Johann Wolfgang Dobereiner: (1810 - 1830) / ed. and explained. Julius ship. Weimar: Böhlau, 1914.
• " Johann Wolfgang Dobereiner ". Publisher: [ sl ]: [ sn], 1880 From: . Weimarische newspaper. Sunday supplement -. Dated 14 November 1880.
• Letters of Grand Duke Carl August and Goethe's to Dobereiner / ed. Oskar Schade. Weimar: Böhlau, 1856.
• In memory of Johann Wolfgang Dobereiner: For his friends and students in near and far / [Ed: Carl F.; MJ Schleiden; O. L. B. Wolff; Fri bat ]. Jena: Schreiber, 1849.
• Member of several parts of the " German pharmacist book / by JW Dobereiner and Franz Dobereiner ", Stuttgart, mugs Publisher 1842 ff ( Digitized edition of the University and State Library Dusseldorf ) 1 Pharmaceutische technology and Waarenkunde. 1842
• 2, plan view of the entire ChemieAbth. 1, Outline of chemistry. 1848
• 3 Pharmaceutische chemistry. 1847