I did some research. The most primitive means of making enriched uranium uses a device called a "calutron". It was abandoned by the U.S. and other nations because it is the costliest (requires huge amounts of power). As far as I can tell it does not use UF6. Here's a quote:
"In this process, uranium atoms are ionized (given an electrical charge) then sent in a stream past powerful magnets. The heavier U-238 atoms are deflected less in their trajectory than the lighter U-235 atoms by the magnetic field, so the isotopes separate and can be captured by collectors. The process is repeated until a high concentration of U-235 is achieved. An American version of the EMIS process, featuring "calutrons", was used in the Manhattan Project. EMIS was also the principal process pursued by the Iraqi uranium enrichment effort."
The UN had many calutrons destroyed post Desert Storm.
However:
" Tracking Number: 209554
(920114)
"Title: Iraq has admitted receiving components from German companies that would have enabled it to produce enough uranium for three or four nuclear bombs a year. UN Report. (920114)
"Date: 19920114
"Text:
*POL208
"01/14/92 UNITED NATIONS REPORT, TUESDAY, JANUARY 14
"U.N. TEAM FINDS NEW IRAQI NUCLEAR EVIDENCE
"Iraq has admitted receiving components from German companies that would have expanded its ability to produce enough uranium for three or four nuclear bombs a year, the United Nations said January 14.
"The significance of the admission, the U.N. said, is that Iraq, which had previously admitted research and development activities in the field of gas centrifuge enrichment, has now acknowledged that it was pursuing a production-scale program of uranium enrichment by this method.
"This acknowledgement will help the United Nations form a clearer picture of some of the sensitive aspects of the Iraqi nuclear program. The information provided as the basis for the present inspection related to some of the components essential for the construction of 10,000 centrifuges, according to a U.N. spokesman who asked not be identified.
"A nuclear inspection team headed by Dr. Maurizio Ziffero of the International Atomic energy Agency (IAEA) and the deputy executive director of the U.N. Special Commission overseeing the destruction of Iraqi Weapons, Dr. Robert Gallucci, went to Iraq after receiving detailed information from the German government on exports by German companies to Iraq in the years before the gulf war.
"According to the German government, the exports were "significant items and materials" related to Iraq's gas centrifuge uranium enrichment program, which was designed to produce weapons grade material. The quantities exported were "appropriate to the production scale program," the spokesman said.
"The U.N. team conducted a "short notice inspection" on January 12. Afterwards, the U.N. team leaders met with the Iraqi foreign minister and top officials of the Iraqi Atomic Energy Commission to present the evidence of the transfers of items and materials from German companies and to ask for explanations as to why these items and materials had not been declared and made available during several previous inspections, the spokesman said.
"On January 13, part of the team led by Ziffero pursued the issue of the centrifuge program, according to the U.N. Following a series of short notice inspections, the nuclear inspection team again met with Iraqi officials who for the first time admitted that Iraq had received items and materials described to them the previous evening.
"Iraqi officials told the team that the items and materials had been destroyed by Iraq on its own initiative immediately after the adoption of Security Council Resolution 687 (which was passed on April 3 and spelled out the conditions for a permanent end to hostilities), the United Nations said. They offered to let the U.N. team see the destroyed materials on January 14.
"The spokesman said that it is still unclear how far the Iraqi program had developed because the Iraqis had destroyed the evidence. U.N. inspectors will now have to determine whether all the equipment has been destroyed or find where Iraq may have hidden the parts or assembled centrifuges.
"Experts have said that if all the centrifuges had been assembled, they could have produced about 75 to 100 kilograms of enriched uranium, which would be enough for three or four bombs a year."
--Boris