Study On Preparation Of Metal-alkoxides Directly Based On Highly Actived Metal

A series of activated magnesium (aluminum)-based materials were prepared byhigh-energy ball milling in inert atmosphere. Scanning electron microscopy (SEM),specific surface test (BET) and particle size distribution test were used to characterize theproperties of activated magnesium (aluminum)-based materials. The experimental resultsshowed that the high-energy milling was an effective way to improve the reactivity ofmagnesium (aluminum)-based materials, adding the catalyst and co-milled magnesiumcould further enhance the reactivity of magnesium (aluminum)-based material, and thetime of ball milling also played an important role in the activity of magnesium(aluminum)-based material.Using the highly reactive magnesium-based material, without using I2, HgCl2, et al.as catalyst, magnesium methoxide, magnesium ethoxide had been prepared with fast rateand efficiency. A comparison had been made between methanol and ethanol with reactingwith magnesium-based materials and comparative study of the active material,magnesium-based and I also studied of the reaction’s difference between active materialreact with and methanol or ethanol, with or without ball milling process, catalyst added ornot to the magnesium-based activated material’s activity with methanol, and the impactof ball milling time, the effect of initial reaction temperature on the magnesium-basedactivated materials react with ethanol. The study result showed that the reaction rate andefficiency were effected by alcohol’s acidity (pKa value); magnesium-based materialexperienced ball milling process when react with methanol display a significantlydifferent reaction phenomenon compare with the material without ball milling, the addingof CoCl2had made the system reaction efficiency further improved; the longer themilling time, the higher initial reaction temperature, made the magnesium-based materialwith better activity,thus, had a higher reaction rate and efficiency with ethanol.On the basis of the preparation of a single metal alkoxide, this paper had studied thefactors that influence the preparation of magnesium/aluminum double alkoxide directlyon the preparation of magnesium/aluminum activated material. To obtain the optimumconditions, we had experiment from the starting material selection, milling time, addingCCl4to explore the preparation of Mg-Al double alkoxide respectively. At last,conclusions were as follows: magnesium, aluminum powder with little Bi as the started material had the highest reaction efficiency，reaching54.80%; by comparing the differentMg-Al-based activated material，results have been get as follows： the sample ball milledfor1h showed excellent chemical reactivity in compare with the samples ball milled0.5h,2h with the yield coming to54.66%; the addition of CCl4has shorten of the reaction timeand the reaction efficiency also has been improved.In addition, the paper also studied the preparation of metal alkoxides with lanthanum.By using high energy ball milling method, the magnesium or aluminum based activatedmaterial with La had been prepared which was used to react with methanol, ethanol to getmetal alkoxides containing lanthanum. SEM, XRD, XRF, XPS were used to characterizethe properties of the hydrolysate products. The results showed that La has beensuccessfully introduced into the metal alkoxide matrix.