(1)盐酸(硫酸、硝酸);Al 2 O 3 +6H + =2Al 3+ +3H 2 O;Fe 2 O 3 +6H + =2Fe 3+ +3H 2 O (2)NaOH;H + +OH - =H 2 O;Fe 3+ +3OH - =Fe(OH) 3 ↓;Al 3+ +4OH - =AlO 2 - +2H 2 O (3)NaAlO 2 +CO 2 +2H 2 O=Al(OH) 3 ↓+NaHCO 3 (4)若用NaOH溶液溶解铝土矿,则有部分SiO 2 溶解在NaOH溶液中生成硅酸钠,最后使加热制得的 Al 2 O 3 混有SiO 2 杂质 |