Synthesis of ThN using a Carbothermic Reduction to Nitridation Process

Journal Article · Wed Jun 15 04:00:00 EDT 2016 · Transactions of the American Nuclear Society

OSTI ID:22992095

Parkison, A. J.; Nelson, A. T. ^[1]

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1. Los Alamos National Laboratory, P.O. Box 1667, Los Alamos, NM, 87545 (United States)

The thorium fuel cycle has several advantages when compared to the uranium fuel cycle. Not only is thorium more abundant than uranium, it also avoids many of the disadvantages which are inherent to the uranium fuel cycle. For example, the thorium fuel cycle does not result in significant formation of long lived, highly toxic transuranics that are inevitably formed in the uranium fuel cycle. The fissile U-233 that is created through neutron capture of Th-232 is also more proliferation resistant than the Pu-239 created from the uranium fuel cycle, because of the buildup of U-232, a source of extremely hazardous gamma emitters. Additionally, thermal reactors which utilize the thorium fuel cycle may be used to destroy transuranics through transmutation as opposed to the fast reactors that are typically required for the uranium fuel cycle. The result is that not only does the thorium fuel cycle avoid the production of transuranic actinides, it may also be used to destroy the inventory of these isotopes within existing reactors. The work presented here investigates the fabrication of ThN so that its properties may be studied to determine its feasibility as a nuclear fuel within a thorium fuel cycle. While both ThO{sub 2} and ThN have melt points higher than the metal, one of the potential advantages of using ThN instead of ThO{sub 2} is that it has a 28% higher fertile density. Additionally, previous investigations have suggested that ThN has substantially higher thermal conductivity when compared to ThO{sub 2} fuel. This suggests that if a (Th,U)N solid solution can be shown to behave similarly to (U,Pu)N, the nitride fuel form would possess a significant advantage over (Th,U)O{sub 2} which has poor thermal conductivity. A carbothermic reduction to nitridation (CTR-N) process has been utilized extensively at LANL for the production and study of UN, but this type of process has not been used for the fabrication of high purity ThN. The work presented here describes the development of a similar process which will be used to fabricate bulk ThN for subsequent experimental study. (authors)

• OSTI ID: 22992095
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Journal Issue: 1 Vol. 114; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
FABRICATION
FAST REACTORS
NEUTRON REACTIONS
NITRIDATION
NUCLEAR FUELS
PLUTONIUM 239
PROLIFERATION
REDUCTION
THERMAL CONDUCTIVITY
THERMAL REACTORS
THORIUM
THORIUM 232
THORIUM CYCLE
THORIUM NITRIDES
THORIUM OXIDES
TRANSMUTATION
URANIUM
URANIUM 232
URANIUM 233