超声波对铝酸钠溶液种分成核粒度的影响

Influence of ultrasound on the nuclei particles size of gibbsite precipitation from aluminate caustic solutions

通过对铝酸钠溶液种分过程中氢氧化铝粒径为1～3μm的粒子质量信息进行分析,考察了超声波强化处理对铝酸钠溶液二次成核的影响.实验结果表明:在较低温度(55℃)下,氢氧化铝固体中成核粒子数明显较多,表明超声波能够促进铝酸钠溶液的二次成核;在60℃和65℃实验条件下,虽然成核细颗粒数高于未用超声波强化的铝酸钠溶液的颗粒数,但远低于55℃实验条件下的细颗粒数,表明超声波强化促进二次成核,随温度升高,成核作用下降;在55℃时,低频超声波比高频超声波产生更多的成核粒子,低频超声波强化种分有更强的二次成核强化作用.

The secondary nucleation of sodium aluminate solutions treated with ultrasound during the decomposition was studied by analysing mass of aluminum hydroxide nuclei, whose diameter is between 1 μm and 3 μm. The results show that there are more nuclei during the precipitation of aluminium hydroxide than that without ultrasound at 60 ℃ and 65 ℃, and fewer than that at 55 ℃ with ultrasound. The quantity of nuclei from the liquors with low frequency are more than those with high frequency at 55 ℃. The results indicate that the secondary nucleation is promoted by ultrasound, and the promoter action decreases with the increase of temperature, and the promoter action with low frequency ultrasound is better than that with high frequency.