Impact of leach on lead vanado-iodoapatite [Pb5(VO4)3I]: An infrared and Raman spectroscopic study

Synthesis of lead vanadate iodoapatite utilizing dry mechanochemical process

“…This is in agreement with the previous reports [2,7,24,25]. There are several possibilities for what occurred at the surface of iodoapatite immersed in water, e.g., OH À replaced I À to form a OH À rich apatite layer [25], or iodine was leached out with lead and left a lead vanadate (or lead vanado-phosphate) layer on the surface [7]. A diffusion process of iodine through those layers of secondary products is supposed to control the leach rate [7].…”

“…8 indicates that the amount of leached iodine is the largest among the three elements, which implies that iodine was not leached out by a simple congruent dissolution of bulk apatites. This is in agreement with the previous reports [2,7,24,25]. There are several possibilities for what occurred at the surface of iodoapatite immersed in water, e.g., OH À replaced I À to form a OH À rich apatite layer [25], or iodine was leached out with lead and left a lead vanadate (or lead vanado-phosphate) layer on the surface [7].…”

“…According to the results by Zhang et al [25], a most likely way for the iodine leaching to take in these cases was substitution by OH À rather than coleaching with Pb 2+ accompanied by Pb(OH) 2 reprecipitation, while in the case of present work, co-leaching with Pb 2+ was probably dominant because the amount of leachant was abundant for Pb 2+ dissolution. Now suppose that the OH À rich apatite layer formed by I À M OH À exchange served as a stronger protective layer against ongoing leaching of iodine than lead vanadate layers formed by simultaneous dissolution of lead and iodine, the higher leach rate would be observed by the present leach test.…”

Hydrothermal synthesis of Cu3(OH)2V2O7·nH2O nanoparticles and its application in lithium ion battery

“…As shown in infrared spectrum in the wavelength region of 300-4000 cm −1 , the high wavenumber vibration located at 3531, 3470 and 3044 cm −1 correspond to water and hydroxyls vibration modes, and the low wavenumber vibration located at 900, 847, 804, 763, 562, 531, 505 and 419 cm −1 are attributed to tetrahedral VO 4 and octahedral CuO 6 vibration modes in the network. The vibration located at 1012, 1409, 1437, 1920 and 1974 cm −1 may ascribe to HCO 3 − that derives from hexamethylenetetramine [21]. It shows similar vibration with that reported in the literature for copper pyrovanadate [18].…”

The durability of iodide sodalite

“…Spectroscopic studies have suggested that an ion exchange mechanism may operate for this wasteform [7]. We also subjected a portion of the iodide vanadinite to a 3 day leach test in a KCl based leachant.…”