Titanium derived nuclear cleanup agents

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Nuclear proliferation is one of the most dangerous and troubling issues facing humanity. The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) was established to monitor worldwide nuclear activities. In addition to seismic stations, CTBTO maintains nearly 100 sites for the detection of radioactive isotopes of xenon which only occur during nuclear explosions or if nefarious isotopes (such as plutonium) are being produced. The background level of xenon isotopes coming from legitimate power and medical isotope reactors is generating so much background that the confidence level in spotting rogue nuclear activities is no longer at an acceptable level. Ag-ETS-10 is an extraordinary xenon adsorbent capable of removing xenon byproducts generated in legitimate nuclear activities. ETS-10 is in fact a series of polymorphs which do not all behave the same when interacting with silver (and thus, xenon). Identifying and synthesizing individual polymorphs of ETS-10 for silver exchange and xenon removal could well identify the most active forms and magnify the already extraordinary xenon concentrating power of ETS-10. This work will prepare and characterize polymorphs of ETS-10 as well as generate a framework substitution of ETS-10 to establish a maximum xenon binding power. Promising materials will be sent to CTBTO in an interactive program to mitigate xenon background issues and allow surer detection of rogue nuclear operations. ******ETS-2 is an exchangeable high surface area nanotitanante. Unlike molecular sieves ETS-2 has all of his active sites (~ 7 eq/kg) on its surface and has no porosity. Much like ETS-10, ETS-2 will template the formation of silver nanoparticles (generally about 5 nm) on its surface. Silver particles readily interact with gaseous iodine because all silver particles on ETS-2 are on the crystallite exterior and not on the interior which in humid streams can be `flooded' with water. The silver on ETS-2 is essentially all reactive towards gaseous iodine even at relatively high humidity. Gaseous iodine is one of the major pollutants generated by nuclear reactors. It currently is captured by massive beds of carbon adsorbents which pose large-scale disposal problems. A material like Ag-ETS-2 has ~ 3 orders of magnitude greater iodine capture capacity than carbon. Developing this to a finished product would allow miniaturization of iodine capture from nuclear reactors with proportionally lower disposal issues. In this effort, the silver capacity of ETS-2 will be maximized and binding and forming techniques established to make the materials into a robust, usable product. Promising materials will be forwarded in a collaborative effort with the Atomic Energy Canada Ltd at their Chalk River facility. **