粗晶粒仲钨酸铵制备研究

STUDY ON THE PREPARATION OF MACROCRYSTALLINE AMMONIUM PARATUNGSTATE.

运用试验设计方法，较系统地研究了各种工艺参数对钨酸根离子缩聚成仲钨酸铵（ＡＰＴ）沉淀的影响规律，并对其缩聚结晶的动力学机理进行了初步探讨。实验结果表明，钨酸铵溶液自生晶核后的ｐＨ值及其控制范围△ｐＨ对其生长速率有显著影响，在主期蒸发温度（９０±５）℃、ｐＨ值７．９±０．１、常压连续蒸发８ｈ，可以制得费氏平均粒度４０μｍ以上球形均匀仲钨酸铵产品。

All kinds of technical parameters and their rules on the preparation of macrocrystalline ammonium paratungstate(APT)were studied by means of intercross experimental method,the mechanism of kinetics on crystal growth by condensation-polymerization was simply discussed.The experimental results show that the APT with the average Fuss grain size above 40 μm can be obtained under the following conditions:controlling pH value 7.9±0.1,evaporation temperature 90℃±5℃ and evaporation time 8 h.