Abstract:
In this study, we focused our interest on the synthesis of a porous nanofertilizer having an
apatitic structure from a raw natural phosphate in alkaline medium. To obtain this nanofertilizer
type, the natural phosphate rock initially enriched by sieving, was submitted to chemical
extraction in presence of an alkaline salt as a digesting agent. The obtained apatite was treated
with a cationic surfactant in order to improve the porosity of the final product. The results of
analyzes obtained by combining X-ray diffraction technique, B.E.T. measurements and TFIR
infrared spectroscopy clearly showed that the obtained product was a nanoporous apatite. The
apatite obtained by this combined process would be an important intermediate for the
manufacturing of other various products of phosphate derivatives. It should be noted that this
process is very effective to remove the elements with an acidic valence such as silica, organic
carbon, chromium VI and vanadium V. On the other hand, Titanium and Yttrium, which have
amphoteric valences, remain with Apatite in amorphous form and are thus reactive. The elements
with a basic valence are difficult to remove by this process (Mg, Sr, Ca, Cd, Zn, Cu, Ce). The
metals belonging to the actinides group, in particular uranium, areremoved at a rate of 40%
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