Separating nozzle stage in the pilot plant of the Institute of Nuclear Process Engineering (IKVT) at Karlsruhe Nuclear Research Center, photographer unknown, November 18, 1969, black-and-white negative. KIT Archives 28028/01306.
In 1955, physical chemist Erwin Willy Becker (1920–2011) developed a new method for separating the uranium isotope 235U, which contains 235 neutrons, from the much more common isotope 238U with 238 neutrons. Due to its fissile properties, 235U is valuable for the generation of energy and has applications in nuclear weapons as well. Becker’s innovative idea suggesting the prospect of a new enrichment technology brought him to Karlsruhe Nuclear Research Center, where he directed the Institute of Nuclear Process Engineering until 1988. The process Becker developed involves passing uranium, which is gaseous when combined with fluorine, through a millimeter-sized nozzle that curves tightly. In this process, the heavier 238U atoms accumulate on the outer wall of the curve, while the lighter 235U atoms concentrate on the inner wall. A peeler installed in the gas flow separates out the 235U-enriched portions of the gas stream. This apparatus is known as a separating nozzle. The separating nozzle technology was developed to industrial maturity at Karlsruhe Nuclear Research Center. Decades of collaborative development together with industrial partners aimed to make this technology viable for commercial use. A separating nozzle system made at the Nuclear Research Center was acquired by Brazil, but after it was installed, it never went into production. One lasting benefit of the work at the Institute of Nuclear Process Engineering was the development of a method for producing very small and precisely crafted structures, which had been necessary for the nozzles. The institute’s focus shifted entirely toward microstructure technology, after which it has been named since 1989. kn
To me, the separating nozzle represents the transition from the Nuclear Research Center to KIT. The investigation on isotope separation, which, just like nuclear energy technology as a whole, ultimately led to a dead end, laid the foundation for microstructure engineering, which currently forms the basis of numerous forward-looking developments in the areas of information technology, health care, and alternative sources of energy. It furthermore prepared the way for the very much smaller structures of nanotechnology. Mathias Heckele, Karlsruhe Institute of Technology, Institute of Microstructure Technology