| Hydrated thoria was precipitated from aqueous solution of
Th(N03) 4.6H,O with concentrated ammonia. X-ray and electron
diffraction showed the precipitate to be amorphous. TE micrographs
showed the individual particle sizes to be in the range 50-100 A with
larger agglomerates of the order of 1000-3000 A. X-ray line broadening
indicated average crystallite sizes in the range 17 to 394 A for
the powdet's calcined between 300° and 800°C. Infrared spectra
showed absorption bands of OH, NO and NO, radicals in the
amorphous as well as calcined materials, their intensities decreasing
at higher calcination temperatures. Green pellets of ThO, powder
pressed in the range 27.2--109.5 KN.cm-2 gave green densities in the
range 3.34-4.92 gm.cm-• and isothermal sintering of the compacts
in the temperature range of 1233°-1509°C for 1.5-9 hrs yielded
densities in the range 72-96% of theoretical. |
