Hydrogen production on Ni loaded apatite-like oxide synthesized by dissolution-precipitation of natural phosphate

A calcium phosphate oxide with composition analogous to the apatite phosphate, was synthesized by dissolution and precipitation of Moroccan natural phosphate, then, used as a carrier for deposition of different amount of nickel (2.5, 5, 10 wt%). The so obtained support and the resulting catalysts were characterized by several techniques, such as ICPAES, XRD, BET, FT-IR, DRS, TPR. XRD characterization showed that the support has the crystalline structure typical of apatite and the chemical composition was close to that of fluoroapatite with some fluoride partially substituted by hydroxide ions. After impregnation of Ni, a portion of Ca2þ ions of the support was exchanged by Ni2þ ions, as confirmed by UVevisibleeNIR analysis. The prepared catalysts were tested in the methane dry reforming reaction without performing any reduction pre-treatment except the exposure to the reaction mixture. High catalytic activity at 700 C and good stability in the production of hydrogen were registered for such Ni loaded samples suggesting a good resistance to coke poisoning according to the basic nature of the support.