Monday, October 06, 2008

How a single patent changed the world

Nature Geoscience recently noted we are at the 100th anniversary of Haber's patenting the ammonia synthesis work.

In an article titled 100 Years Of Ammonia Synthesis: How A Single Patent Changed The World , ScienceDaily wrote: The [Nature] feature appears 100 years after Fritz Haber filed his patent on the ‘synthesis of ammonia from its elements’ for which he was later awarded the 1918 Nobel Prize in Chemistry.

A patent in question, German 235421 was filed Oct. 13, 1908 and issued June 8, 1911.

A relevant US patent on the use of osmium is 971,501, issued Sept. 27, 1910 on a filing of Aug. 13, 1909, which states

Several attempts have hitherto been made to produce ammonia on a large scale from its elements by passing them over a catalyst, but up to the present not much success has been met with.

In order that the process should be successful, it is advisable that the combination take place at as low a temperature and as quickly as possible, Since when the temperature increases the concentration of the ammonia formed decreases.
We have now discovered that on passing gases containing nitrogen and hydrogen over osmium large quantities of ammonia can be obtained. This result is surprising, since it differs in this respect from the allied metal platinum (see Zeitschrift fur Elektrochemie, vol. 14, p. 191).

In carrying out this invention, osmium can be used either in the form of the metal (preferably in a very finely divided condition) or in the form of a compound of the metal which upon being used becomes converted into metallic osmium, and the metal or its compound can be used either alone or in admixture with other substances or compounds. The osmium can be employed, for instance, in the form of metallic osmium, or it may be precipitated on a suitable carrier, such for instance, as quartz, asbestos, clay, and the like. Asbestos containing ten per cent. of osmium is suitable for use. Further instead of metallic osmium, other suitable osmium compounds can be employed, such for instance as osmium oxid hydrate (prepared by the action of formaldehyde on an alcoholic solution of osmic acid, cf. Berichte 40, 1387), which under the action of the hydrogen used is converted into metallic osmium; or Fremy's salt can be used as the starting material, and either alone or mixed with an indifferent substance, or precipitated on a suitable carrier. Under the action of hydrogen it becomes converted into metallic osmium. The reaction can be carried out at ordinary pressure, but we prefer to carry it out under increased pressure, for instance at from 100 to 200 atmospheres.

Contemplate also United States Patent 1068967.

It is worthwhile to note that patent incentives drove the research. From chemistryexplained -->

Although most researchers soon dropped the topic because of little success, from 1904 on Haber continued investigating both approaches under contract with the chemical company BASF (Badische Anilin- und Sodafabrik), who offered him money, equipment, and patent shares. The path to ammonia turned out to be more promising if the reaction rates were increased by catalysts at high temperature. Thermodynamics required low temperature, however, to move the equilibrium toward higher yields of ammonia. Because thermodynamics predicted the same effect at high pressure, Haber and his coworkers at BASF searched for temperature and pressure conditions that a reaction vessel could withstand and that resulted in acceptable yields. Success came only when they found more effective catalysts, at first with osmium and uranium. In addition, they pushed the equilibrium to the product side by continuously drawing off ammonia from the reaction mixture and continuously providing new reactants, resulting in 1909 in a steady flow reactor at about 100 atm and 500°C (932°F) with ammonia yields of some 10 percent.

Haber demonstrated that the production of ammonia from the elements was feasible in the laboratory, but it was up to Carl Bosch, a chemist and engineer at BASF, to transform the process into large-scale production. The industrial converter that Bosch and his coworkers created was completely revised, including a cheaper and more effective catalyst based on extensive studies in high-pressure catalytic reactions. This approach led to Bosch receiving the Nobel Prize in chemistry in 1931, and the production of multimillion tons of fertilizer per year worldwide.

The ScienceDaily piece did not mention Haber's work in chemical warfare, and the Haber relation. See the IPBiz post

Patents and Fritz Haber in Law & Order on 9 Jan 08


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