Preparation And Purification Of High Purity Al₂O₃ By Alcohol Aluminum Method

This article mainly studied using alcohol preparation of high purity alumina and aluminum impurities of purification methods of alumina.Experiment chooses aluminium powder and isopropyl alcohol, and aluminum in isopropyl alcohol or using iodine as catalyst, isopropanol aluminum is obtained by vacuum distillation.Isopropanol aluminum in removing impurity results show that the amount of activated carbon for 8 g/L, the Fe element removal rate reached 43.52%, 0.15 g/L, for the amount of molecular sieve Fe removal rate reached 39.14%, join in isopropanol aluminum EDTA0.005 g/L, the mixing time of 45 min,the aluminum oxide of iron impurity removal rate was 69.59%.By ion exchange resin concentration before and after the experiment of different known D001 macroporous strong acid styrene type cation exchange resin of ion resin of magnesium ions removal rate was 45.14%, the strongly acidic styrene type ion resin 001 * 7 of calcium removal rate was 50.93%.Used in the process of the preparation of isopropanol aluminum vacuum distillation experiment method also helps to improve the purity of alumina.The isopropanol aluminum in 80 ℃ constant temperature water bath isopropanol aluminum continuous water fully hydrolysis, precursor aluminum hydroxide.Will aluminumhydroxide dried at 200℃, and respectively heated at 400℃,600℃, 800℃, 1000℃, 1200℃ high temperature calcination.By phase analysis of Al（OH）₃in 400℃, 600℃, 800℃, 1000℃ and1200℃, phase shift of burnt products are as follows:Al（OH）₃→η-Al₂O₃→γ-Al2_O3→θ-Al₂O₃ →α- Al₂O₃。With the increase of temperature, sintering product specific surface area and average particle size decreases, and the whiteness value increased gradually.Specific surface area from 248.7 ㎡ /g reduce to 9.781 ㎡/g, the average particle size from 20.21μm decreased to 8.49μm. Whiteness value increased from 85.8 to 99.9.