Fritz Haber
Fritz Jakob Haber was a German chemist who received the Nobel Prize in Chemistry in 1918 for his invention of the Haber process, a method used in industry to synthesize ammonia from nitrogen gas and hydrogen gas. This invention is important for the large-scale synthesis of fertilizers and explosives. It is estimated that a third of annual global food production uses ammonia from the Haber–Bosch process, and that this food supports nearly half the world's population. For this work, Haber has been called one of the most important scientists and industrial chemists in human history. Haber also, along with Max Born, proposed the Born–Haber cycle as a method for evaluating the lattice energy of an ionic solid.
Haber, a known German nationalist, is also considered the "father of chemical warfare" for his years of pioneering work developing and weaponizing chlorine and other poisonous gases during World War I. He first proposed the use of the heavier-than-air chlorine gas as a weapon to break the trench deadlock during the Second Battle of Ypres. His work was later used, without his direct involvement, to develop the Zyklon B pesticide used for the killing of more than 1 million Jews in gas chambers in the greater context of the Holocaust.
Following the Nazis' rise to power in 1933, Haber resigned from his position. Already in poor health, he spent time in various countries before Chaim Weizmann invited him to become the director of the Sieff Research Institute in Rehovot, Mandatory Palestine. He accepted the offer but died of heart failure mid-journey in a Basel, Switzerland hotel on 29 January 1934, aged 65.
Early life and education
Haber was born in Breslau, Kingdom of Prussia, into a well-off Jewish family. Though Haber was a common family name in Breslau, the family has been traced back to a great-grandfather, Pinkus Selig Haber, who was a wool dealer from Kempen. An important Prussian edict of 13 March 1812 determined that Jews and their families, including Pinkus Haber, were "to be treated as local citizens and citizens of Prussia". Under such regulations, members of the Haber family were able to establish themselves in respected positions in business, politics, and law.Haber was the son of Siegfried and Paula Haber, who were first cousins who married in spite of considerable opposition from their families. Haber's father Siegfried was a well-known merchant in the town, who had founded his own business in dye pigments, paints and pharmaceuticals. Paula experienced a difficult pregnancy and died three weeks after Fritz's birth, leaving Siegfried devastated and Fritz in the care of various aunts. When Haber was about six years old, Siegfried remarried to Hedwig Hamburger. Siegfried and his second wife had three daughters: Else, Helene, and Frieda. Although his relationship with his father was distant and often difficult owing to Fritz being associated with the death of his first wife, Haber developed close relationships with his stepmother and his half-sisters. Siegfried displayed love and care for his three daughters but never fully accepted Fritz as his son.
By the time Fritz was born, the Habers had to some extent become assimilated into German society. He attended primary school at the Johanneum School, a "simultaneous school" open equally to Catholic, Protestant, and Jewish students. At age 11, he went to school at the classical school in Breslau, in a class evenly divided between Protestant and Jewish students. His family supported the Jewish community and continued to observe many Jewish traditions, but were not strongly associated with the synagogue. Haber identified strongly as German, less so as Jewish.
Haber successfully passed his examinations at the St Elizabeth gymnasium in September 1886. Although his father wished him to become an apprentice in the dye company, Haber obtained his father's permission to study chemistry at the Friedrich Wilhelm University in Berlin, with the director of the Institute for Chemistry A. W. Hofmann. Haber was disappointed by his initial winter semester in Berlin, and arranged to attend Heidelberg University for the summer semester of 1887, where he studied under Robert Bunsen. He then returned to Berlin, to the Technische Hochschule in Charlottenburg.
In the summer of 1889, Haber was conscripted and left university to perform his one-year volunteer service in the Sixth Field Artillery Regiment. Upon its completion, he returned to Charlottenburg where he became a student of Carl Liebermann. In addition to Liebermann's lectures on organic chemistry, Haber also attended lectures by Otto Witt on the chemical technology of dyes.
Liebermann assigned Haber to work on reactions with piperonal for his thesis topic, published as Ueber einige Derivate des Piperonals in 1891. Haber received his doctorate cum laude from Friedrich Wilhelm University in May 1891, after presenting his work to a board of examiners from the University of Berlin, since Charlottenburg was not yet accredited to grant doctorates.
With his degree, Haber returned to Breslau to work at his father's chemical business, where their relationship continued to have difficulties. Through Siegfried's connections, Haber was assigned a series of practical apprenticeships in different chemical companies to gain experience. These included Grünwald and Company, an Austrian ammonia-sodium factory, and the Feldmühle paper and cellulose works. These experiences drove Haber to learn more about technical processes, and persuaded his father to let him spend a semester at the Polytechnic College in Zürich, studying with Georg Lunge. In the Fall of 1892, Haber returned again to Breslau to work in his father's company, but the two men continued to clash and Siegfried finally accepted that they could not work well together.
Haber had received a PhD in chemistry by this time, but his father required him to take handwriting courses and become a salesman to learn more about the company. Haber urged his father to transfer from natural to synthetic dyes, but his father refused. Eventually, his father followed global business trends and switched to synthetic dyes. Haber's next suggestion, during a cholera epidemic, was for his father to purchase calcium hypochlorite, which at the time was the only known method for the prevention of cholera. That epidemic ended up being isolated and resulted in their possession of a sizeable amount of unused calcium hypochlorite, which is unstable. This caused a rift between Siegfried and Haber, with his father telling him to go back to his university studies as he did not belong in the business world.
Early career
Haber then sought an academic appointment, first working as an independent assistant to Ludwig Knorr at the University of Jena between 1892 and 1894. During his time in Jena, Haber converted from Judaism to Lutheranism, possibly in an attempt to improve his chances of getting a better academic or military position. Knorr recommended Haber to Carl Engler, a chemistry professor at the University of Karlsruhe who was intensely interested in the chemical technology of dyes and the dye industry, and the study of synthetic materials for textiles. Engler referred Haber to a colleague in Karlsruhe, Hans Bunte, who made Haber an Assistent in 1894.Bunte suggested that Haber examine the thermal decomposition of hydrocarbons. By making careful quantitative analyses, Haber was able to establish that "the thermal stability of the carbon-carbon bond is greater than that of the carbon-hydrogen bond in aromatic compounds and smaller in aliphatic compounds", a classic result in the study of pyrolysis of hydrocarbons. This work became Haber's habilitation thesis.
Haber was appointed a Privatdozent in Bunte's institute, taking on teaching duties related to the area of dye technology, and continuing to work on the combustion of gases. In 1896, the university supported him in travelling to Silesia, Saxony, and Austria to learn about advances in dye technology.
In 1897 Haber made a similar trip to learn about developments in electrochemistry. He had been interested in the area for some time, and had worked with another privatdozent, Hans Luggin, who gave theoretical lectures in electrochemistry and physical chemistry. Haber's 1898 book Grundriss der technischen Elektrochemie auf theoretischer Grundlage attracted considerable attention, particularly his work on the reduction of nitrobenzene. In the book's foreword, Haber expresses his gratitude to Luggin, who died on 5 December 1899. Haber collaborated with others in the area as well, including Georg Bredig, a student and later an assistant of Wilhelm Ostwald in Leipzig.
Bunte and Engler supported an application for further authorization of Haber's teaching activities, and on 6 December 1898, Haber was invested with the title of Extraordinarius and an associate professorship, by order of the Grand Duke Friedrich von Baden.
Haber worked in a variety of areas while at Karlsruhe, making significant contributions in several areas. In the area of dye and textiles, he and Friedrich Bran were able to explain theoretically steps in textile printing processes developed by Adolf Holz. Discussions with Carl Engler prompted Haber to explain autoxidation in electrochemical terms, differentiating between dry and wet autoxidation. Haber's examinations of the thermodynamics of the reaction of solids confirmed that Faraday's laws hold for the electrolysis of crystalline salts. This work led to a theoretical basis for the glass electrode and the measurement of electrolytic potentials. Haber's work on irreversible and reversible forms of electrochemical reduction are considered classics in the field of electrochemistry. He also studied the passivity of non-rare metals and the effects of electric current on corrosion of metals. In addition, Haber published his second book, Thermodynamik technischer Gasreaktionen: sieben Vorlesungen trans. Thermodynamics of technical gas-reactions: seven lectures, later regarded as "a model of accuracy and critical insight" in the field of chemical thermodynamics.
In 1906, Max Le Blanc, chair of the physical chemistry department at Karlsruhe, accepted a position at the University of Leipzig. After receiving recommendations from a search committee, the Ministry of Education in Baden offered the full professorship for physical chemistry at Karlsruhe to Haber, who accepted the offer.