Thorium carbide

Table 3. Physical Properties of Uranium and Thorium Carbides...

Fluidized-bed CVD was developed in the late 1950s for a specific application the coating of nuclear-fuel particles for high temperature gas-cooled reactors. PI The particles are uranium-thorium carbide coated with pyrolytic carbon and silicon carbide for the purpose of containing the products of nuclear fission. The carbon is obtained from the decomposition of propane (C3H8) or propylene... 

Thorium carbide, ThC2, deposited from the iodide. 

Metal acetylides incandesce on heating in selenium vapour barium acetylide at 150°C, calcium acetylide and strontium acetylide at 500°C and thorium carbide at an unstated temperature. 

Thorium carbides, 24 761, 4 689—690 Thorium carbonate, 24 765 Thorium carboxylates, 24 768-769 Thorium chlorides, 24 762-763 Thorium complexes allyl, 24 773... 

Thorium forms many compounds, including the following example compound Thorium carbide Th + 2C — ThCj. This compound is used as a nuclear fuel. 

The method described below for the preparation of thorium bromide combines the method of Troost and Ouvrard3 with that of Moissan and Martinsen.2 The former passed bromine over a heated mixture of thorium dioxide and carbon but did not purify the thorium bromide formed. The latter prepared the halide by the action of bromine on heated thorium carbide and purified the product by sublimation, first in a current of hydrogen and... 

In thorium carbide the Of ions are lying flat in parallel planes in such a way that two axes are equally lengthened with respect to the third. These structures are shown in Fig. 7-8. Lithium carbide, Li2Q, (Section 3-2) has a structure similar to that of CaQ. 

Thorium carbides (ThC, ThC2) and uranium carbides (UC, UC2) exhibit metallic properties, but in other properties differ significantly from the carbides of the subgroups of the IVth, Vth and Vlth groups of the periodic table. Their hardnesses are substantially lower (see Table 5.6-1), they are pyrophoric and are easily hydrolyzed in water or weak aeids. Their only economic importance is as carbidie fuels in nuelear technology, particularly for high temperature and breeder reactors which are currently in the evaluation phase. 

Uranium and thorium carbides are not typical hard materials... 

---