Georg Kassner

Georg Max Julius Kaßner (born February 4, 1858 in Lubin , † March 30, 1929 in Munster ) was a Prussian chemist , pharmacist and secret councilor .

Life

Kaßner was born as the son of the district court counselor J. Kaßner († 1906).

As was customary at the time, before he could become a university professor and researcher in chemistry and pharmacy , he had to be trained as a pharmacist . Then he was able to pursue his long-cherished wish and began to study in Basel , Zurich and Wroclaw . During his studies in 1880 he became a member of the Teutonia Zurich fraternity . After graduating, he was obliged to do military service in Poznan and then returned to Wroclaw in 1884. In 1886 he married Maria Heintze.

First, secret government councilor Thomas August Theodor Poleck (1821–1906) employed Kaßner as an assistant, and it was here in particular that he experienced impressions that strongly influenced his later life's work. He devoted his whole life to the scientific research of lead oxide compounds . He began to research plumbates intensively under Poleck and for the first time produced calcium plumbate (Ca ₂ PbO ₄ ). In 1889 he invented a process for extracting oxygen from the air with the help of this compound , because calcium plumbate splits with pure carbonic acid at 700 ° C into calcium carbonate , lead oxide and oxygen. The by-products calcium carbonate and lead oxide form calcium plumbate again when heated in air. Both processes are symbolized in the following formulas:

${\displaystyle \mathrm {Ca_{2}PbO_{4}+2\ CO_{2}\longrightarrow (2\ CaCO_{3}+PbO)+O} }$

${\displaystyle \mathrm {2\ CaCO_{3}+PbO+4\ N+O\longrightarrow 2\ CO_{2}+4\ N+Ca_{2}PbO_{4}} }$

This process became the subject of his habilitation thesis A new process for utilizing the oxygen in the air and the compounds on which it is based , Breslau in 1889, and patented in 1896.

As the successor to Paul Arthur Meyer (1850–1922), Kaßner accepted the call to the Royal Theological and Philosophical Academy in Münster in 1891 as an associate professor for pharmaceutical chemistry and chemical technology. This academy and later Westfälische Wilhelms-Universität was at the time the central office for pharmacy in the province of Westphalia , so this step represented a decisive leap in his career. In addition to pharmaceutical chemistry, he also had a teaching position here for technological and forensic chemistry. In addition, he set up private training courses. He attached particular importance to training in measurement analysis because, according to his findings, measurement analysis is of particular importance for pharmacists and chemists. In German Pharmacopoeia of that time newest 6th edition this view was fully confirmed.

In 1895 he wrote a treatise that was important at the time: The description of a process for the extraction and separation of cane sugar and other types of sugar from impure sugar solutions containing foreign substances, such as B. from molasses, vegetable juices and the like. A few years after the development of the process for oxygen production, Linde invented the Lindesche process , in which pure, liquid oxygen is also produced at significantly lower costs. From an economic point of view, the Kassner process could no longer assert itself, but it could not be influenced by it. In the years 1899 to 1903 further specialist articles and treatises followed, such as:

• A new case of crystal chloroform , leprous chloroform , 1900
• About the animal experiments with poisonous gases, especially with carbon oxide , 1901 - in it he described the Gréhant experiments ( Louis François Nestor Gréhant (1838–1910)) and in particular the finding that hemoglobin poisoned by carbon monoxide is treated more effectively by oxygen than by air
• On the formation of red lead through light and air , 1903

After the law on phosphorus fuses of May 10, 1903 (repealed on September 7, 2005) came into force, he gave valuable suggestions on the use of plumbates in the manufacture of safe, fire-hazardous matches that contained the calcium plumbate he had invented.

After many attempts, Kaßner succeeded in 1911 in developing an even more economical process for obtaining oxygen from the air, using the double compound of sodium plumbite and sodium manganate , which he called plumboxan . Here, air is split into two phases into pure oxygen and almost pure nitrogen . Further advantages of this process are the significantly lower reaction temperature of 400 ° C and a carbonic acid source is no longer necessary. This type of oxygen production is represented by the following formula:

${\displaystyle \mathrm {(Na_{2}PbO_{3}=Na_{2}MnO_{4})+4\ H_{2}O\longrightarrow O+(Na_{4}PbO_{4}=MnO_{2})+H_{2}O} }$

${\displaystyle \mathrm {(Na_{4}PbO_{4}=MnO_{2})+4\ H+O\longrightarrow Na_{2}PbO_{3}+Na_{2}MnO_{4}+4\ N} }$

In 1912 an important contribution to the knowledge of the aether followed . During the First World War , more and more nitric acid compounds were required for the armaments industry . In order to gain independence from sodium nitrate , Kaßner expanded his research area accordingly and in 1922 developed a catalyst for the oxidation of ammonia by means of the double compound of barium metaplumbate and barium manganate - at 500 ° C, the transfer of oxygen from the air to the ammonia molecule with the formation of nitric acid and nitrous gases.

Kaßner enjoyed great trust from his fellow citizens in Münster and took an active part in public life. Among other things, this was also a prerequisite for a very long tenure as a city ​​councilor at 15 years . Upon reaching the appropriate age limit, Kaßner retired in 1926 . A cold in autumn 1928 was followed by pneumonia , which he succumbed to on March 30, 1929 in Münster. He left his wife, four sons and three daughters. He could look back on 35 years of teaching and research.

Works

• Georg Kaſsner: A new process for utilizing the oxygen in the air and the compounds on which it is based. In: Polytechnisches Journal . 274, 1889, pp. 136-142. ( Pp. 183–190 , pp. 226–231 , pp. 270–276 )
• Process for the production of alkaline earth salts of poly lead acids . In: The chemical industry . Volume 19, No. 2 , 1896, p. 35-36 (report on patent specification DP 82583).
• Process for the production of lead oxide . In: The chemical industry . Volume 19, No. 5 , 1896, pp. 101 (report on patent specification DP 82985).
• K. et al .: Process for the production of oxygen, respectively. of oxygen and carbonic acid from calcium plumbate . In: The chemical industry . Volume 19, No. 9 , 1896, pp. 187 (report on patent specification DP 85020).
• A new case of crystal chloroform, leprous chloroform . In: Archives of Pharmacy . tape 239 , no. 1 , 1901, ISSN  0365-6233 , p. 44-48 .
• About the formation of red lead through light and air . Contribution to the chemical effect of light . In: Archives of Pharmacy . tape 241 , no. 9 , 1903, ISSN  0365-6233 , p. 696-708 .
• Contribution to the knowledge of the aether . In: Archives of Pharmacy . tape 250 , 1912, pp. 436-447 .

literature

• Friedrich W. Sierp: Georg Kaßner † . In: Chemiker-Zeitung . Vol. 35, no. 42 , 1929, ISSN  0009-2894 , pp. 409 f .

Individual evidence

1. ^ Ernst Elsheimer (ed.): Directory of the old fraternity members according to the status of the winter semester 1927/28. Frankfurt am Main 1928, p. 242.
2. ↑ German Pharmacopoeia . 6. revised Edition. von Decker, Berlin 1926, p. XXXV − XXXVIII .