种分过程1,2-辛二醇对氢氧化铝粒度及形貌的影响

研究了1,2-辛二醇对铝酸钠溶液种分过程的影响。结果表明,1,2-辛二醇对铝酸钠溶液种分过程产生抑制作用。1,2-辛二醇的添加浓度、实验温度以及苛碱浓度等因素对1,2-辛二醇改善铝酸钠溶液种分效果具有显著影响。添加浓度小于1.25 mmol/L时,1,2-辛二醇对铝酸钠溶液的抑制程度很小,产品氢氧化铝的粒度分布基本维持与未添加时一致;添加浓度超过1.5 mmol/L,抑制作用非常明显,产品氢氧化铝粒度曲线主峰明显左移,平均粒度减小。温度越低,苛碱浓度越大,1,2-辛二醇对铝酸钠溶液分解抑制作用越大,产品氢氧化铝的细化程度越大。X射线衍射(XRD)显示,加入1,2-辛二醇后种分产品的晶型不变。

Effect of 1,2-Octanediol on the Particle Size and Morphology of Aluminium Hydroxide Precipitated from Seeded Sodium Aluminate Solution

The effect of non-ionic surfactant-1,2-Octanediol on the seed precipitation of sodium aluminate solution has been investigated.The results show that 1,2-Octanediol has inhibitory effect on the precipitation.The concentration of 1,2-Octanediol,temperature and caustic concentration of liquor can obviously affect the seed precipitation of sodium aluminate solution.When the concentration of 1,2-Octanediol in the solution is less than 1.25 mmol/L,the inhibitory effect on gibbsite precipitation is limited and the particle size is almost the same as that without additive.However,when the concentration of 1,2-Octanediol in the solution is more than 1.5mmol/L,the inhibitory effect is large and the particle size is decreased.Lower temperature and higher caustic concentration of liquor will greatly decrease the particle size.The results of X-ray diffraction show that the crystal structure of Al(OH)3 products remains the same with additive.