1/26/2009 Colloquium - Jeff W. Eerkens

Jeff W. Eerkens University of Missouri - Columbia

Event Info

Title:  Laser Enrichment of Uranium

Date: Jan 26, 2009
Location: 3105 Etcheverry Hall
Time: 4-5pm

Abstract

Present nuclear plants are fueled by uranium enriched to 3.5 % U-235, obtained from natural uranium with 0.7% U-235. Future fast breeder reactors will burn (re)processed mixtures of Th-232, U-233 through -238, Pu-239, and other transuranics obtained from once-through fuels. Clearly, selective isotope enrichment is an important component of the nuclear fuel cycle. To date enrichment has been carried out by gaseous diffusion, centrifuge, and electromagnetic "calutron" technologies developed during and shortly after WW-II (1940s and 1950s). Since the birth of the laser in 1960 new schemes for uranium isotope separation with lasers have been explored, using U vapor isotope-selectively ionized by UV or VIS lasers (AVLIS), or by isotope-selective vibrational excitation of UF6 gas with an IR laser (MLIS). The AVLIS process was successfully demonstrated at Livermore at a cost of about $2 Billion but was found barely competitive with well-developed centrifuge technology. Less expensive MLIS processes that explored dissociation/reaction of laser-excited 235UF6 with a scavenger gas to yield solid 235UF5[X] separable from gaseous 238UF6, were also found lacking because of the need for chemical processing. However a condensation-repressing MLIS technique which requires only inert carrier gas and no reactant appears commercially viable and competitive with centrifuges. This technique resembles Becker's jet diffusion separation scheme which was briefly investigated in the late (pre-laser) 1950s as a possible replacement for Gaseous Diffusion. While the supersonic free jet in the Becker process separates 235UF6 from 238UF6 due to mass difference ΔM = 3, in the new laserized scheme a mass difference of ΔM = 355 amu between laser-excited 235UF6 monomers and super-cooled non-excited 238UF6:238UF6 dimers drives molecular migration and separation. Two condensation-repression schemes labeled CRISLA and SILEX which use different lasers will be reviewed and compared with centrifuge enrichment.

Speaker Biography

Dr. Jeff W. Eerkens received an MS degree in Nuclear Engineering in 1957, and a PhD in Engineering Science in 1960 from the University of California at Berkeley. During completion of his PhD thesis, he worked full-time as a nuclear engineer at Aerojet-General-Nucleonics in nearby San Ramon. He was physicist-in-charge for the "critical" assembly of two AGN-211 reactor installations at Rice Institute and the University of Oklahoma. After graduating in 1960, Dr. Eerkens worked as an engineer-scientist for several high-tech companies in the Los Angeles area (Aerospace, Northrop, Garrett AiResearch) to develop space satellite power and laser systems. In 1977, he founded the LISCHEM corporation to manufacture high-power infrared lasers and laso-chemical reactors. Three years later he formed a partnership with industrialist Dick Griot (founder of Melles-Griot) to finance the R&D of his patented CRISLA process for laser enrichment of Uranium. In 1985, the CRISLA R&D effort resulted in the formation of Isotope Technologies Inc (ITI). The CRISLA process and patents were subsequently transferred in 1990 to a joint venture between ITI and CAMECO (Canadian Mining and Energy Company, the largest Uranium mining company in the world). However after Russia entered the world market in 1993 with ten-year stockpiles of reactor-grade Uranium offered at below-cost prices, CAMECO halted all further CRISLA development. Dick Griot then donated ownership in CRISLA to his alma mater, the University of Missouri at Columbia (MU), to use surplus CRISLA equipment for research on laser separation of medical isotopes for MURR (Missouri University Research Reactor). Dr. Eerkens moved from California to Columbia, Missouri in 1994, joining MU as a research professor to re-assemble the CRISLA laboratory and formulate an R&D program for separation of medical isotopes. In 2006 he returned to California to be near his grandchildren and son in UC-Davis. Dr Eerkens recently published a book "The Nuclear Imperative" issued by Springer, ISBN 1-4020-4930-7, and is promoting combustion engines that burn ammonia to replace petro-fuels.