Editing Neptunium (section)

==Role in nuclear waste==
Neptunium accumulates in commercial household ionization-chamber [[smoke detector]]s from decay of the (typically) 0.2 [[microgram]] of americium-241 initially present as a source of [[ionizing radiation]]. With a half-life of 432 years, the americium-241 in an [[smoke detector#Design|ionization smoke detector]] includes about 3% neptunium after 20 years, and about 15% after 100 years.

Under [[Redox|oxidizing]] conditions, neptunium-237 is the most mobile [[actinide]] in the [[deep geological repository]] environment of the [[Yucca Mountain]] project in [[Nevada]].<ref>{{cite web| url = https://fas.org/sgp/othergov/doe/lanl/pubs/00818052.pdf| title= Yucca Mountain| access-date = 2009-06-06}}</ref> This makes it and its predecessors such as [[americium-241]] candidates of interest for destruction by [[nuclear transmutation]].<ref>{{cite journal| doi =10.1016/S0029-5493(03)00034-7| title =Deep-Burn: making nuclear waste transmutation practical| date =2003| author =Rodriguez, C| journal =Nuclear Engineering and Design| volume =222| pages =299–317| issue =2–3| display-authors =4| last2 =Baxter| first2 =A.| last3 =McEachern| first3 =D.| last4 =Fikani| first4 =M.| last5 =Venneri| first5 =F.| bibcode =2003NuEnD.222..299R}}</ref> Due to its long half-life, neptunium will become the major contributor of the total [[radiotoxicity]] at Yucca Mountain in 10,000 years. As it is unclear what happens to the non-reprocessed [[spent fuel]] containment in that long time span, an extraction and transmutation of neptunium after spent fuel reprocessing could help to minimize the contamination of the environment if the nuclear waste could be mobilized after several thousand years.<ref name="Nevada">{{cite web|url = http://newscenter.lbl.gov/feature-stories/2005/11/29/getting-the-neptunium-out-of-nuclear-waste/|date =2005-11-29| title = Getting the Neptunium out of Nuclear Waste|first = Lynn|last = Yarris|publisher = Berkeley laboratory, U.S. Department of Energy|access-date = 2014-07-26}}</ref><ref>{{cite web|url = http://www.pnl.gov/main/publications/external/technical_reports/PNNL-14307.pdf|title = Existing Evidence for the Fate of Neptunium in the Yucca Mountain Repository|author = J. I. Friese|display-authors = 4|author2 = E. C. Buck|author3 = B. K. McNamara|author4 = B. D. Hanson|author5 = S. C. Marschman|date = 2003-01-06|publisher = Pacific northwest national laboratory, U.S. Department of Energy|access-date = 2014-07-26}}</ref><!--{{cite journal | doi = 10.1002/anie.200501281 | volume=44 | title=Optical Absorption and Structure of a Highly Symmetrical Neptunium(V) Diamide Complex | year=2005 | journal=Angewandte Chemie International Edition | pages=6200–6203 | last1 = Tian | first1 = Guoxin}}-->
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