1 is prepared by reacting aluminum sulfate solution with ammonium sulfate solution, cooling and crystallizing, centrifugal separation, washing and drying.

2. Bauxite reacts with sulfuric acid to produce aluminum sulfate, which is precipitated by gel collapse, and then ammonium sulfate is added at night to react with aluminum sulfate at 100℃ to produce ammonium aluminum sulfate, and then concentrated. Cooling, crystallizing, separating and washing to obtain the finished product. Reaction formula:

Al2O3+3H2SO4——Al2(SO4)3+3H2O

Al2(SO4)3+(NH4)2so 4+ 12H2O

3. Aluminum hydroxide reacts with sulfuric acid to generate aluminum sulfate, and then reacts with ammonium sulfate, and the product is concentrated, cooled and crystallized, centrifugally dehydrated and dried to obtain the finished product. Reaction formula:

2Al(OH)3+3h2so 4——Al2(SO4)3+6H2O

Al2(SO4)3+(NH4)2so 4+ 12H2O

4. At the high temperature of 400℃, aluminum oxide and ammonium sulfate can react to produce aluminum sulfate.

4(NH4)2s 04+a 1203 = 2 nh4al(S04)2+6nh 3+3h 20