Acta Phys. -Chim. Sin. ›› 1998, Vol. 14 ›› Issue (09): 821-825.doi: 10.3866/PKU.WHXB19980911

• ARTICLE • Previous Articles     Next Articles

Study on Thermal Decomposition of Sodium Paratungstate Na10H2W12O42·27H2O

Liu Shi-Jun, Chen Qi-Yuan, Zhang Ping-Min, Liu Min-Na   

  1. Department of Chemistry,Certral South University of Technology,Changsha 410083
  • Received:1997-12-01 Revised:1998-04-07 Published:1998-09-15
  • Contact: Liu Shi-Jun

Abstract:

In this paper, the preparation of sodium paratungstate Na10H2W12O42•27H2O(SPTB ) and its characterization by X-ray diffraction, Raman spectrum and chemical analysis have been studied. The thermal decomposition of SPTB has been also studied. The overall mechanism of decomposition involves seven separate stages. The first four stages are dehydration stages, which occur at about 331K, 353K, 403K and 588K respectively, and which correspond to the loss of10H2O, 9H2O, 5H2O and 4H2O respectively. The fifth stage, which occurs at about 691K, is a phase transformation of an intermediate. The sixth stage, which occurs at about 733K, is the formation of the mixture of Na2W2O7 and Na2W4O13.The first five stages are all reversible.

Key words: Sodium paratungstate, Thermal decomposition