Preparation of forsterite (Mg2SiO4) powders via an aqueous route using magnesium salts and silicon tetrachloride (SiCl4)

Forsterite (Mg2SiO4) powders were prepared by mixing SiCl4 with aqueous sol utions of either Mg(CH3COO)(2). 4H(2)O or Mg(NO3)(2). 6H(2)O and heating th e powdered gel. The powders were characterised using thermal analysis (DTA and TGA), X-ray diffraction (XRD), nitrogen adsorption surface area analysi s (BET) and transmission electron microscopy (TEM). On heating, MgO and ens tatite (MgSiO3) were observed in addition to forsterite. On heating to 1200 degrees C, forsterite was the dominant phase in the powders produced from Mg(NO3)(2). 6H(2)O, and MgO was the dominant phase in the powders produced from Mg(CH3COO)(2). 4H(2)O. The primary particle sizes of these powders wer e between 100 and 500 nm, which remained the same on heat treatment. Howeve r, higher temperatures gave rise to an increase in the size and densities o f the agglomerates of primary particles.