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2-Propanol decomposition at 200 °C on magnesium oxide prepared by the hydrolysis of magnesium ethoxide (sol−gel method) is reported. With hydrochloride acid, acetic acid, or ammonia as hydrolysis alkoxide catalysts, the acidity and the selectivity to propene of the catalysts follow the sequence, MgO (HCl) > MgO (acetic acid) > MgO (ammonia). In contrast, the basicity of the samples, defined as the ratio dehydrogenation rate/dehydration rate, is found to be depending on the particle size of the catalysts. The basicity trend found is MgO (acetic acid) > MgO (ammonia) > MgO (HCl) and it correlates well with the particle size determined by the Rietveld refinement.

The crystalline structure of the M 2 CuWO 6 phases with M = Ba or Sr was obtained from X-ray powder diffraction at room temperature with CuKa radiation. The phases are isostructural with tetragonal unit cells, space group I4/m and Z = 2. The parameters for the Sr 2 CuWO 6 phase are: Mr = 518.6, a = 5.42693 (5) A, c = 8.4087(1) A, V = 247.65(1) A 3 , D x = 6.954 Mg/m 3 , [I = 77.75 mm 1 , F(000) = 454, R = 0.0375 for 24 reflections; the parameters for the Ba 2 CuWOg phase are: Mr = 618.1, a = 5.56392(8) A, c = 8.6274(1) A, V = 267.08(1) A 3 , D x = 7.683 Mg/m 3 , n = 157.0 mm 1 , F(000) = 526, R = 0.0506 for 27 reflections. Cell parameters were obtained from Rietveld refinement. The crystalline structure is based on the perovskite structure. It is laminar with ordered alternating WO 6 deformed octahedra and CuO 2 planar squares along the [110] direction, joined by corners and rotated perpendicular to the [001] direction. The samples are electrical insulators.