March 12, 2009, Updated September 13, 2012

The method developed at Ben-Gurion University denatures the plutonium created in large nuclear reactors by adding Americium. (Image: Plutonium pellet; Courtesy of the US Department of Energy via Wikimedia Commons)

“It is easier to denature plutonium than to denature the evil spirit of man,” Albert Einstein once said. Einstein’s rueful sentiment may, in fact, be proven true by engineers at Ben-Gurion University of the Negev who have developed a denaturing technique that could help combat the evils of nuclear proliferation.

The method denatures the plutonium created in large nuclear reactors by adding Americium (Am 241), a form of the basic synthetic element found in commercial smoke detectors and industrial gauges. Once denatured, the plutonium is unsuitable for use in armaments.

An article on the technique and findings will appear next month in the international journal Science and Global Security, for peer-reviewed scientific and technical studies relating to arms control, disarmament and nonproliferation policy.

Currently, five major countries produce large nuclear reactors: the US, Russia, Germany, France and Japan. The article suggests that if these countries all agreed to add the denaturing additive into all plutonium, it would prevent nuclear fuel being used for weapons.

Peaceful purposes, not warfare

“When you purchase a nuclear reactor from one of the five countries, it also provides the nuclear fuel for the reactor,” explains Prof. Yigal Ronen, of BGU?s Department of Nuclear Engineering, who headed the project. “Thus, if the five agree to insert the additive into fuel for countries now developing nuclear power — such as Bahrain, Egypt, Kuwait, Libya, Malaysia, Namibia, Qatar, Oman, United Arab Emirates, Saudi Arabia and Yemen — they will have to use it for peaceful purposes rather than warfare.”

Nuclear fuel used in nuclear reactors has two isotopes of uranium. One is fissionable, while the other is not. The unfissionable component undergoes a number of nuclear reactions, turning some of it into plutonium. The plutonium also includes fissionable and unfissionable components. The amount of fissionable components created in nuclear reactors is enough to be used as nuclear weapons.

“Countries that purchase nuclear reactors usually give the spent fuel back to the producer,” explains Ronen. “They wouldn’t be able to get new plutonium for weapons if it is denatured, but countries that make nuclear fuel could decide not to denature it for themselves.”

Ronen originally worked on Neptonium 237 for the purpose of denaturing plutonium, but switched to Americium, which is meant for pressurized water reactors (PWRs), such as the one being built in Iran.

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