Preparation of ammonium paratungstate with coarse grain by evaporating crystallization

Abstract

A new technology for the crystallization of ammonium paratungstate with coarse grain has been studied. The factors influencing the physi-chemical properties of ammonium paratungstate crystal, such as temperature, concentration, seed crystal, agitation, etc. were examined. It is necessary to keep high temperature and low concentration in the process, and the addition of seed crystal and agitation with air is also in favor of the system. Ammonium paratungstate crystal with particle size of 36–42 µm and apparent density of 2.0–2.2 g · cm⁻³ were obtained by controlling suitable technological parameters.

Keywords

evaporating crystallization / coarse grain / ammonium paratungstate

References

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