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Nano γ-A1203 because of its high activity , a series of excellent properties of large surface area , strong adsorption is widely used in structural ceramics, catalyst carrier , microfiltration and fluorescent materials . Γ-A1203 does not exist in nature as well as the small particle size of nanoparticles reunion , so how to prepare the dispersion , the reunion is less controllable grain size nano γ-A1203 has become the research focus . The subject prepared alkoxide hydrolysis method nano γ - A1203 , a the alkoxide hydrolysis process hydrolysis temperature , concentration of aluminum isopropoxide , alcohol - water ratio and hydrolysis try using rotary evaporator dry alternative to traditional on nano γ-A1203 performance impact ; oven drying method to obtain higher isopropanol recoveries , investigated hydrated alumina phase transition and its physical and chemical changes in the roasting process , and comprehensive analysis of the endpoint temperature , holding time , heating rate , as well as focus on the temperature holding time on the nano γ-A1203 performance relationship . The results show that : alkoxide hydrolysis , drying and roasting stage process conditions nano γ-A1203 particle size distribution and reunion . When hydrolysis temperature 80 ° C , the alcohol phase initial concentration of aluminum isopropoxide , 0.20 mol / L alcohol-water molar ratio of 1:3 can be obtained smaller particles , particle size distribution, good dispersion of γ- A1203 powder body; rotary evaporated to dryness to obtain a higher recovery of the isopropanol , and the drying time is short , the drying efficiency is improved ; end temperature and the heating rate in the calcination process have a significant effect on the performance of the powders of γ-A1203 , the main impact of the end temperature the degree of crystallinity of alumina , grain size and its specific surface area, the rate of temperature rise is mainly to affect the grain size and the product of the agglomeration particle size. The end of the higher temperature , the slower the heating rate , the larger the crystal grain , almost the entire crystal growth , specific surface area declined the powder agglomeration significantly improved . The optimum conditions : roasting endpoint temperature of 850 ° C , the end temperature for 30 min, heating rate of 3 ° C / min ; uniform, dense alumina membrane preparation of nano-alumina powder coating obtained after milling 9h holes and the gap rarely , to meet the industrial requirements of the alumina coating .
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