A new production method of ammonium metatungstate—Donnan dialysis method

Abstract

A new method for production of ammonium metatungstate (AMT) directly from ammonium tungstate solution—Donnan dialysis method is advanced. Laboratory experiments are conducted by a Donnan dialysis cell with the membrane area of 140 mm ×200 mm. The result shows that the transformation rate of AMT reaches 370 g-WO₃/(m²·h), the recovery ratio of AMT by the Donnan dialysis method is nearly 100%, and the loss of tungsten is less than 0.2%. It has been proved that the Donnan dialysis method is effective for production of AMT.

Keywords

membrane separation / Donnan dialysis / tungsten / ammonium metatungstate

References

[1] Shi Yahua. Effect of impurities in AMT solution on activity of tungstencontaining catalyst for hydrodeoxydization and hydrosulfurization. Tungsten Industry in China(in Chinese), 1992(8):11

[2] Xu Zhichan, Zhang Ping. The present and future of AMT production technology. Tungsten Industry in China(in Chinese), 1991(3):12

[3] Liu Xia, Sun Jian, Lu Tiejun, et al. Preparation of APT and AMT by solvent extraction. Tungsten Industry in China(in Chinese), 1993(5):14

[4] KojimaT, FurusakiS, SatoK. A fundamental study on recovery of copper with a cation exchange membrane. J Chemical Engineering, 1982, 60: 650-650

[5] HoC C, JanD S, TsaiF N. Membrane diffusion-controlled kinetics of ionic transport. J Membrane Sci, 1993, 81: 287-287

[6] MiyoshiH. Diffusion coefficients of ions through ion-exchange membranes for donnan dialysis using ions of the same valence. Chemical Engineering Science, 1997, 52(7): 1087-1087