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研究了以硫酸铝铵和碳酸氢铵为原料合成碳酸铝铵的工艺条件．在实验条件范围内，将硫酸铝铵溶液以低于1．2L．h－1的速度加入到碳酸氢铵溶液中，可合成碳酸铝铵；在其它操作条件下，获得的产物为γ－AlOOHγ－AlOOH升温过程中的物相变化次序为：γ－AlOOH→γ－Al2O3→δ－Al2O3→θ－Al2O3→α－Al2O3;而碳酸铝铵的相变次序为：碳酸铝铵→无定型Al2O3→θ－Al2O3→α－Al2O3碳酸铝铵转变为θ－Al2O3和α－Al2O3的温度均比γ－AlOOH低约100℃γ－AlOOH在1200℃煅烧1h方可完全转变为α－Al2O3，其颗粒尺寸为150um；粉体经1450℃、2h烧结相对密度为84.46％；而碳酸铝铵在1100℃煅烧1h就可完全转变为α-Al2O3，其颗粒尺寸为70um，粉体在相同的烧结条件下相对密度可达97.80％
The conditions for the synthesis of ammonium aluminum carbonate from ammonium aluminum sulfate and ammonium bicarbonate were studied. Under the experimental conditions, the ammonium aluminum sulfate solution was used at less than 1.2L. h-1 was added to the ammonium bicarbonate solution to synthesize aluminum ammonium carbonate; under the other operating conditions, the product obtained was γ-AlOOHγ-AlOOH. The order of the phase changes during the temperature rising is: γ-AlOOH → γ- Al 2 O 3 → δ-Al 2 O 3 → θ -Al 2 O 3 → α -Al 2 O 3; while the phase transition of ammonium aluminum carbonate was: ammonium aluminum carbonate → amorphous Al 2 O 3 → θ-Al 2 O 3 → α-Al 2 O 3 Al 4 O 4, The temperature of Al2O3 is about 100 ℃ lower than that of γ-AlOOH. The γ-AlOOH calcined at 1200 ℃ for 1h can be completely transformed into α-Al2O3 and the particle size is 150um. The relative density of powder sintered at 1450 ℃ for 2h is 84.46% Ammonium carbonate can be completely transformed to α-Al2O3 after calcined at 1100 ℃ for 1h, the particle size is 70um, the relative density of the powder under the same sintering conditions can reach 97.80%