Certificate of honorary membership in the Bavarian Association of Gas and Water Experts for Hans Bunte, October 23, 1910, maker: Franz Xaver Weinzierl, Munich, 38.8 × 30.0 × 2.0 cm, autograph document on parchment with an ink miniature, in an ornamental leather binding with brass appliqués. KIT Archives 27055/67.
This exquisitely crafted certificate is one of the numerous honors awarded to Hans Bunte (1848–1925), a distinguished chemist who served as professor of technical chemistry at Karlsruhe Polytechnic starting in 1887. Bunte made significant contributions to fuel chemistry and combustion technology, laying important foundations for the heating industry. His research focused primarily on the production of gas from coal. Known as illuminating gas or town gas, this energy source, which comprises approximately 50 % hydrogen and 20 % methane, was widely used for lighting and heating until it was gradually replaced by natural gas in the 1960s. Hans Bunte, who also served as secretary general of the German Association of Gas and Water Experts (DVGW) since 1884, played a pivotal role in organizing Germany’s gas and water supply infrastructure. His influence, together with the petroleum research of his colleague Carl Engler (1842–1925), established KIT’s longstanding focus on energy, which continues today. The former Gas Institute at the Polytechnic is now part of the Engler-Bunte Institute at KIT. The colored ink drawing above the text of the certificate depicts the Gas Institute, which was founded at Karlsruhe Polytechnic at Bunte’s initiative. In 1907 this institute served as the central teaching and research center for the DVGW, in association with the Polytechnic. The chemical processes involved in gas production were its primary research focus, and it also provided annual training courses for gas works management personnel throughout Germany. kn
In a history of the Gas Institute, written on the occasion of Hans Bunte’s fiftieth anniversary, Johannes Körting characterizes him as having “to seek his life’s work in a dichotomy: either research and teaching activities, or rather the constructive technical-design side.” Hans Bunte’s honorary membership in the Bavarian Association of Gas and Water Experts reflects one side of this dichotomy: the desire to promote the utilization of scientific knowledge in technical industrial practice and everyday life through his professional activities. The other side of his disposition was awakened by Hermann von Fehling, known for Fehling’s solutions for quantitative detection of aldehyde groups in sugars, whom Hans Bunte met during his studies at the Stuttgart Polytechnic between 1865 and 1867. After a brief period at Heidelberg University in 1868 with its great research personalities Bunsen, Kirchhoff, Helmholtz, and Erlenmeyer, Bunte completed his studies in Erlangen in 1869 with a doctoral thesis under the organic chemist von Gorup-Besánez on his self-chosen topic: “Investigations on Urea and Urea Derivatives.” One motivation for these investigations can be inferred from Bunte’s speech on the occasion of the handover of the rectorship at Karlsruhe Polytechnic on October 31, 1896. Bunte outlined numerous examples of how discoveries in chemistry could solve people’s everyday problems and increase their prosperity. For example, he categorized Wöhler’s synthesis of urea as the removal of the barrier “which seemed to have been erected between organic and inorganic nature; the belief that a special force, the live force, was active in the chemical processes in the animal and plant kingdoms to create new forms, had fallen and the door was opened for chemical research to enter the field of plant and animal physiology, agriculture, and medicine.” Bunte’s work on topics from organic chemistry, which he carried out at Munich Polytechnical College with his academic teacher from his time in Heidelberg, Emil Erlenmeyer, in a “meanly paid assistant position,” was presumably based on the same motivation. There he discovered the salts of the S-alkyl esters of thiosulphuric acid. This class of compounds, of which he described the sodium salt of the S-ethyl ester in his habilitation thesis in 1872, has entered the literature under the name “Bunte salts.” They are useful intermediates in chemical syntheses and exhibit bacteriostatic, insecticidal, and fungicidal effectiveness. As a private lecturer, Bunte gave lectures on tar dyes and, in particular on analytical chemistry, which undoubtedly also shaped his scientific approach and methodology. Despite his suc cesses with synthesis and versatility in teaching, the prospects boding at the beginning of his career did not materialize, and more tangible forms of recognition also failed to happen. This may be interpreted as impetus for Bunte to rediscover the technical side of his disposition. The setting for this was provided by his acquaintance with Nikolaus Heinrich Schilling, who was director of the Munich Gas Lighting Company and editor of the technical journal for the gas and lighting utilities and water supply, Journal für Gasbeleuchtung und verwandte Beleuchtungsarten, sowie für Wasserversorgung. He recruited Bunte for this periodical in 1874. The journal was also the organ of the German Association of Gas and Water Experts and its Branch Associations, which Bunte joined in 1875. In close cooperation with Schilling and later as head of the heating test station of the Munich Gas Lighting Company, Bunte carried out numerous experimental studies that formed the scientific basis for the production of gas from coal and its technical application. Hans Bunte introduced the new scientific principles of heating technology and findings by the gas industry into German university teaching for the first time with his lectures on fuels, gas analysis, and combustion at the Munich Polytechnic. Due to the lack of recognition for his work, Bunte left that polytechnic in 1884 without much regret to work full-time for the gas industry. To this end, he had already taken over the editorship of the Journal für Gasbeleuchtung (since 1876, together with Schilling, and from 1883 alone), was chairman of the Deutscher Verein der Gas- und Wasserfachmänner (German Association of Gas and Water Experts) in 1882–1883 and its secretary general from 1885. He held this post until 1909 and was thus a key driving force behind the intensive scientific and technical development of the German gas industry. Carl Engler, who had begun intensive research into the chemistry of crude oil in Karlsruhe, brought about Bunte’s appointment as his successor to the Chair of Chemical Technology at Karlsruhe Polytechnic. The professional connection to Engler had been established through work on the subject of lubricating oils. The rapidly growing opportunities in Karlsruhe nurtured Bunte’s development as an academic teacher and organizer. He introduced new aspects to teaching, emphasizing the economic side of chemical engineering. For the first time, chemistry students gained insight into the economic context and he pushed for training in mechanical engineering subjects to make their collaboration with specialists from outside the field more effective. Together with Engler, he fought for the right of Polytechnics to award doctorates. The expansion of the institute was also linked to Bunte’s cultivation of special fields of technical chemistry, by which the research and teaching there was diversified. At times, up to seven private lecturers worked for Bunte. The field of tar dyes, on which he himself had lectured in Munich, was transferred to these young coworkers and eventually evolved into textile chemistry. Areas of applied physical chemistry and especially electrochemistry were entrusted to Bunte’s young colleagues, in particular, Fritz Haber. But he was not an easy teacher for his young and aspiring colleagues. His former assistant Ernst Terres remembers: “a word of praise was rarely or never spoken after a completed piece of work. The wordless recognition of what had been achieved was already recognition and praise enough.” Despite everything, Fritz Haber characterized his time with Bunte positively: “The 13 years with Bunte were the hardest of my life, but this time of growth, hope, and advancement were the happiest years of my professional career.” The conditions at Karlsruhe meant that research work had to be transferred from industrial applications to the laboratory. As technology progressed, problems of gas purification and gas utilization came to the fore and required ever new scientific methods. As the research topics grew, so did the requirements. The institute responded to this with multiple extensions and expansions. The result was an institute many times the size of what Bunte had found when he was initially appointed. Despite the remarkable pace of development, Bunte felt that laboratory work alone was often insufficient for studying technical processes. From his time in Munich, he had also learned that conducting scientific investigations within a company focused on economic efficiency during normal operations was limited. His solution was, to establish a dedicated scientific testing facility. After years of preparation, during which he secured most of the necessary funding himself, Bunte founded the Teaching and Testing Station of the German Association of Gas and Water Experts in 1907. The institute, affiliated with Karlsruhe Polytechnic and later known simply as the “Gas Institute,” provided the illuminating gas industry with a unique research facility unmatched by any other sector. The many other facets of Hans Bunte’s personality — as Privy Councilor (Geheimer Hofrat), member of the First Chamber of the Baden Diet and of the German Academy of Sciences Leopoldina, and founder of the “gas courses” — can only be briefly noted here. Körting best captured his legacy: “That with this [dual] disposition, he ultimately became one of the pioneering figures who achieved a perhaps unprecedented synthesis of both areas to perfection, perhaps becoming the first chemical engineer in the modern sense, was fortunate for him and even more so for the entire gas industry.” Henning Bockhorn