摘要：

A modified autoclave hypercritical drying procedure has been used to prepare a hydrated form of MgO from Mg(OCH{sub 3}){sub 2} in a methanol-toluene solvent mixture. This material was prepared with 1,000 m{sup 2}/g surface area and 35-{angstrom} crystallite size. Heat treatment of this precursor at 500C under vacuum yielded the dehydrated MgO with 500 m{sup 2}/g surface area and 45-{angstrom} crystallite size. The samples were further characterized by Fourier transform infrared/photoacoustic spectroscopy (FT-IR/PAS), X-ray diffraction, scanning electron microscopy, and chemical analyses. The hydrated precursor contained some residual {minus}OCH{sub 3} groups and was much less crystalline in appearance than conventionally prepared MgO-Mg(OH){sub 2} samples. The dehydrated material was free of {minus}OCH{sub 3} groups and was made up of much smaller crystallites than conventionally prepared MgO.

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