仲钨酸铵蒸发结晶研究

STUDIES ON CRYSTALLIZATION OF AMMONIUM PARATUNGSTATE(APT)FROM SOLUTION OF AMMONIUM TUNGSTATE BY VAPOURIZATION

本文采用正交实验法对由离子交换净化除杂后的钨酸铵溶液蒸发结晶制备仲钨酸铵(APT)的工艺条件进行了研究,探明了影响 APT 结晶粒度大小的主要因素,得到了一定工艺条件下 APT 晶体粒径与其影响因素之间的数学模型。

The studies on process conditions of vapourization for cryst- allizing ammonium paratungstate (APT)from solution of ammonium tungstate purified by the ion-exchange process are reported in this paper It is found through a group of orthogonal experiments that the main factors affecting the particle size and crystal form of APT are temperature,time duration for crystal growth,stirring intensity and the cross-effect of crystal gro- wth time and stirring intensity,The crystal form and morphology of samples of APT crystallized at temperatures of 45℃ and 85℃ were determined by X-ray diffraction analysis and scanning electron microscopy,The experime- ntal date were processed with a model of quadratic regression in order to describe the relationship between the particle size of APT and the correspo- nding operating conditions for crystallization process.