Neptunium trifluoride

Neptunium is fairly reactive and forms some interesting compounds. Examples include neptunium dialuminide (NpAl2) and neptunium beryllide (NpBc3). These compounds are unusual because they consist of two metals joined to each other. Normally, two metals do not react with each other very easily. Neptunium also forms a number of more traditional compounds, such as neptunium dioxide (Np02), neptunium trifluoride (Npp3), and neptunium nitrite (NPNO2). 

Pure neptunium metal can be made by heating neptunium trifluoride (Npp3) with hot barium or lithium metal ... 

NpF3 NEPTUNIUM TRIFLUORIDE 1235 PbC03 LEAD CARBONATE 1279... 

Its importance depends on the nuclear property of being readily fissionable with neutrons and its availability in quantity. The world s nuclear-power reactors are now producing about 20,000 kg of plutonium/yr. By 1982 it was estimated that about 300,000 kg had accumulated. The various nuclear applications of plutonium are well known. 238Pu has been used in the Apollo lunar missions to power seismic and other equipment on the lunar surface. As with neptunium and uranium, plutonium metal can be prepared by reduction of the trifluoride with alkaline-earth metals. 

Manganese trichloride oxide, 4141 Manganese trifluoride, 4335 Mercury(II) bromide, 0269 Mercury(I) fluoride, 4312 Mercury(II) iodide, 4602 Molybdenum hexafluoride, 4365 Molybdenum pentachloride, 4180 Neptunium hexafluoride, 4366 Osmium hexafluoride, 4370 Palladium tetrafluoride, 4347 Palladium trifluoride, 4341... 

Fluorine is used in the separation of uranium, neptunium and plutonium isotopes by converting them into hexafluorides followed by gaseous diffusion then recovering these elements from nuclear reactors. It is used also as an oxidizer in rocket-fuel mixtures. Other applications are production of many fluo-ro compounds of commercial importance, such as sulfur hexafluoride, chlorine trifluoride and various fluorocarbons. 

Neptunium may be prepared in the metallic state by the reduction of its trifluoride with barium vapor at 1,200°C followed by rapid cooling. Its tetraflu-oride may be reduced with excess calcium metal at about 750°C under argon atmosphere. 

The actinides are base metals which require the reduction of a chloride or fluoride with sodium or barium for their isolation. Neptunium, for example, has been made by reducing its trifluoride with barium vapour at 1200°. The need for such drastic methods is understandable because the heats of formation of the ions are as much as three times greater than that of the Pt ion. The metals are silvery white and, except thorium and americium, have high densities. 

With the exception of thorium, the actinides form trihalides. For uranium and neptunium, reduction of the MX4 compounds with hydrogen is necessary, but for the elements from plutonium onwards the action of the carbon tetrahalide or aluminium halide on the dioxide is usually employed. The trifluorides are insoluble but the rest dissolve to give solutions containing ions. 

Neptunium halides. Neptunium forms binary halides in the oxidation states of Np (III, IV, and VI). The trifluoride is prepared by hydrofiuorination of the dioxide, hydroxide, carbonate, oxalate, or nitrate in the presence of hydrogen ... 

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