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Homogeneous hydrolysis of titanium oxo-sulfate and iron(III) sulfate has been used to prepare anatase TiO 2 and ferrihydrite with high specific surface area. Resulting samples were characterised by specific surface area (Brunauer-Emmett-Teller method) and porosity (Barrett-Joyner-Halenda method) measurements, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The samples of anatase TiO 2 and ferrihydrite were evaluated for their ability to degrade chemical warfare agents (sulfur mustard gas, soman and agent VX) to non-toxic products. The largest percentage of mustard gas converted into non-toxic products after the completion of the reaction was 99%.

Tungsten-doped anatase was prepared by a thermal hydrolysis of aqueous solutions of peroxo complexes of titanium and tungsten. The synthesized samples included X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction, Raman spectroscopy, specific surface area, and porosity determination. W doping resulted in a decrease of the unit-cell volume of anatase at lower W contents and an increase at higher W contents. The position of the most intense Raman band of the E g mode (near 147 cm À1 ) also has a local minimum at medium-doped titania (1.1À3.6% W in titania). W doping increases the temperature of anatase-to-rutile transformation by about 100 °C compared with nondoped anatase. The photocatalytic activity of doped titania samples was determined by decomposition of Orange II dye during irradiation at 365 and 400 nm. Specimens with moderate W doping (1.0À3.3% W) perform best: they enhance the corresponding reaction rates 10 times at 365 nm and 5 times at 400 nm, respectively, compared with pure titania obtained under the same set of synthesis conditions.

An autoclave hypercritical drying procedure has been used to prepare precursors of MgO from Mg(OCH 3 ) 2 . This material was prepared with a speci c surface area of 1200 m 2 g 1 . The dehydrated materials consisted of much smaller crystallites than conventionally prepared MgO and were free of OCH 3 groups . The precursors and samples of magnesium oxide were taken for experimental evaluation of their reactivity with mustard. The largest percentage of the conversion mustard into non-toxic products after the elapse of the reaction was 77%.