Synthesis and characterization of a new microporous cesium silicotitanate (SNL-B) molecular sieve

New Fission-Product Waste Forms: Development and Characterization

“…Calculated fraction released (FR%) and normalized Ba leaching rate (NL) data of the product consistency test (PCT) conducted on fresnoite glass (A) and crystal (E), are shown in Table I. The normalized Ba leaching rate (NL) observed for both glass and crystal samples decreased as a function of time, comparable to other titanosilicates 2,3 . The changes in NL values for glass (A) showed more severe drops than crystal (E).…”

“…To incorporate the surface area into the PCT test, the normalized Ba leaching rate (NL) can be calculated by the following equation: NL (g (m 2 d) -1 ) = CV / fAt, where C is the concentration of Ba in the leachate (g/ml); V, the leachate volume (ml); f, the initial fraction of Ba in fresnoite; A, the surface area of the test specimen (m 2 ); and t, the duration of test (days). Surface area was calculated by follows: A = (surface area per unit mass × original mass of the sample), where surface area per unit mass for spherical particles is calculated from the equation: 4πr 2 / ((4/3)πr 3 •d). The radius (r) used was 5 µm determined by BSE images and the density (d) of fresnoite crystal and glass used was 4.44 g/cm 3 and 4.29 g/cm 3 , respectively 1 .…”

Tungsten bronze-based nuclear waste form ceramics. Part 1. Conversion of microporous tungstates to leach resistant ceramics

“…Angular shaped particles with dark contrast analysed as Na 0. 33 major component from the XRD pattern (Fig. 12).…”

“…These are now known to be SNL-A (Cs 2 TiSi 6 O 15 )[32] and SNL-B (Cs 3 TiSi 3 O 9.5 3H 2 O)[33] and the Ti analogue of the mineral Pollucite (CsTiSi 2 O 6 )…”

Effective utilization of waste cathode ray tube glass—Crystalline silicotitanate synthesis

“…Therefore, CST has been recognized as the preferable choice for removing Cs/Sr from nuclear waste, and it was awarded a 1996 R&D 100 award as "one of the 100 most technologically significant product of the year" [31,32]. Thus far, many papers have been published on CST synthesis [33][34][35], generally using titanium isopropoxide/titanium tetrachloride as titanium source and tetraethyl orthosilicate/silicon ethoxide/colloidal silica as silicon source. However, reports on preparing CST using waste CRT glass as silicon source are considerably few.…”