Preparation And Property Study Of Liquid Alkoxide

In this dissertation, the liquid alkoxide at room temperature is synthesized using alcohol and aluminum as raw materials. The effects of hydrolysis factors and drying methods on the properties of alkoxide hydrolysis and alumina are studied. The properties of liquid alkoxide hydrolysis were compared with that of solid alkoxide hydrolysis. The products of alkoxide hydrolysis are tested by XRD, Optical Microscope, Laser Particle Sizer, and SEM.The results indicate that, the drying method has no effect on phase structure of the product synthesized by liquid alkoxide hydrolysis. Meanwhile hydrolysis temperature impact on phase structure greatly. Phase of the product hydrolyzed below 50℃is amorphous. When hydrolyzing at 60℃, the phase of product is pseudo-boehmite. After hydrothermal treatment the phase changed to boehmite. The obtained product also has good crystallinity.The best conditions of liquid alkoxide hydrolysis and drying are as follows: hydrolysis temperature is 80℃, the hydrolysis ratios for 1:3(MOR: H2O), hydrothermal treatment temperature is 160℃, and vacuum distillation drying temperature is 54℃. Under these conditions, small size particles of product can be obtained, in the meanwhile, the particle size distribution is very narrow and dispersion good. The more smaller and uniformer of precursor, the bigger ofγ-alumina powder particles, and the smaller ofα-alumina powder particles and the better dispersion. With the increasing of hydrolysis ratios,α-alumina powder dispersion is worse. In the ratio 1:3, and after 160℃treatment, theα-alumina powder particles are composited of nearly spherical little particles, overcoming the powder reunion deficiencie.By comparasion with hydrolysis properties and alumina performances of two kinds of alkoxide, it is found that the drying temperature and hydrolysis ratios are less impacted on the solid alkoxide. Under the same condition, the sample particles abtained from solid alkoxide hydrolysis are smaller and uniform than that from liqud alkoxide. The hydrolysis ratios is more impacted on the liqud alkoxide, with the water increasing, the sample particles'increase rate are great, and non-uniform. Under the same condition, the composite of theα-alumina powder particles abtained from solid alkoxide hydrolysis are small and dispersion bad.The alcohol recovery rate of liquid alkoxide hydrolysis is higher than that of solid alkoxide hydrolysis, and percent moisture of recovery alcohol from second step hydrolysis is lower, it showed that, under the same condition, the liquid alkoxide hydrolysis is more fully.Liqud alkoxide is first synthesized in this dissertation, and studying the alkoxide hydrolysis properties and alumina performances, which opened a new space for high purity alumina powder industrialization.