Elaboration of an iodine-bearing apatite Iodine diffusion into a Pb3(VO4)2 matrix

Rapid synthesis of Pb5(VO4)3I, for the immobilisation of iodine radioisotopes, by microwave dielectric heating

“…Audubert et al proposed lead iodovanadate, Pb 5 (VO 4 ) 3 I, as a potential immobilisation matrix for the immobilisation of 129 I, with a low iodine leach rate of 0.0025 g m À2 d À1 at pH 6 and 90°C [4]. This compound adopts the apatite structure type, with the large iodide anions immobilised in the one-dimensional tunnels formed by corner sharing VO 4 polyhedra [5], Fig.…”

Thermal and mechanical properties of AgPb9(VO4)6I and AgBa9(VO4)6I

“…Pb 10 (VO 4 ) 6 I 2 [1] and Pb 10 (VO 4 ) 4.8 (PO 4 ) 1.2 I 2 [2] were synthesized by Audubert et al, and the leaching behavior of the latter was reported [2] and other properties of Pb 10 (VO 4 ) 6 I 2 were reported in our previous study [3]. In this study, We tried to synthesize more stable compounds by means of addition of silver.…”

Spark plasma sintering of lead phosphovanadate Pb3(VO4)1.6(PO4)0.4

“…Pb 3 (VO 4 ) 1.6 (PO 4 Germany) and NH 4 H 2 PO 4 (97.5% purity, Prolabo, France) at 1000 • C for 1 h. The obtained powder, was ground in water for 210 min in a planetary ball mill (PM400, Retsch) in a tungsten carbide bowl or for 240 min in an attrition mill (Attritor 01-HD, Union Process) in a zirconia bowl. These powders were then dried at 100 • C. The resulting powders were designated P1 (planetary ball milling) and P2 (attrition milling); their specific surface areas as determined by the BET method (GEMINI 2360, Micromeritics) were 1.0 and 8.0 m 2 /g, respectively.…”

“…2,3 They are synthesized by calcining stoichiometric quantities of lead iodide and lead phosphovanadate according to the following equation: 3Pb 3 (VO 4 ) 2(1−x) (PO 4 ) 2x + PbI 2 → Pb 10 (VO 4 ) 6(1−x) (PO 4 ) 6x I 2 Confined process conditions are necessary to prevent iodine volatilization above 500 • C. For this purpose, additional lead phosphovanadate was used to form an impermeable jacket around a 3Pb 3 (VO 4 ) 2(1−x) (PO 4 ) 2x + PbI 2 core. 4 This requires closure of the open porosity in the jacket prior to the beginning of iodine release, which occurs at about 450-500 • C (based on thermogravimetric analysis of the resulting iodine apatite [1][2][3][4][5] ). This relative low temperature requires unconventional sintering tech- * Corresponding author.…”