由钾长石焙烧渣的酸化溶液制备高纯Al(OH)_3

以钾长石焙烧渣的酸化溶液为原料,Na_2CO_3溶液为沉淀剂制备高纯Al(OH)_3.实验考察了溶液终点pH值、反应温度、陈化时间、Na_2CO_3质量浓度对沉铝率的影响,得到优化工艺条件.采用化学成分分析,XRD,SEM,FTIR对Al(OH)_3粉体进行表征.结果表明:在反应温度50℃的条件下,加入质量浓度为300 g/L的Na_2CO_3溶液调节Al_2(SO_4)_3溶液,使其终点pH值至4.8,控制陈化时间40 min,沉铝率可达99%.得到的Al(OH)_3粉体为非晶态结构,颗粒均匀,表面粗糙,有团聚现象.

Preparation of High Purity Al(OH)3from the Sulfating Solution of Potash Feldspar Roasting Residue

Employing the sulfating solution of potash feldspar roasting residue as raw materials and Na₂CO₃ solution as precipitator， the high purity Al(OH)₃ was prepared. The effects of the pH value at the end of precipitating Al， reaction temperature， aging time and the mass concentration of Na₂CO₃ solution on the precipitation rate of Al were investigated. Al(OH)₃ powder was characterized by chemical component analysis， X-ray diffraction(XRD)， scanning election microscope(SEM)， and Fourier transform infrared spectroscopy (FTIR). The optimum technological conditions， which could guarantee the precipitation rate of Al more than 99%，were to keep reaction temperature at 50℃， add the Na₂CO₃ solution with the mass concentration of 300g/L into Al₂(SO₄)₃ solution， control the pH value at 4.8 and the aging time for 40min. The features for the produced Al(OH)₃ powder were that the crystal was amorphous， the particles were homogeneous with rough surface and the particles agglomeration occurred.