Dissolving behavior of ammonium paratungstate in (NH4)2CO3–NH3·H2O–H2O system
2018
Abstract The effects of temperature, ammonia concentration and ammonium carbonate concentration on the dissolving behavior of ammonium paratungstate were studied in (NH 4 ) 2 CO 3 –NH 3 ·H 2 O–H 2 O system. The results show that rising temperature, prolonging duration, increasing ammonia concentration and decreasing ammonium carbonate concentration favor dissolving of ammonium paratungstate at temperature below 90 °C, while the WO 3 concentration decreases after a certain time at temperature above 100 °C. Furthermore, the undissolved tungsten exists in the form of either APT·4H 2 O below 90 °C or pyrochlore-type tungsten trioxide above 100 °C. In dissolving process, the ammonium paratungstate dissolves into paratungstate ions followed by partially converting to tungstate ion, resulting in the coexistence of the both ions. This study may provide a new idea to exploit a novel technique for manufacturing ammonium paratungstate and pyrochlore-type tungsten trioxide.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
14
References
2
Citations
NaN
KQI