Hydrochloric Acid → Sodium metatungstate

Participants

Reaction Steps

First, a sodium tungstate aqueous solution having a pH of 9 or greater (sample 1) was prepared. A sodium polytungstate aqueous solution (sample 2) was prepared by adding hydrochloric acid to sample 1 for adjustment to a pH of 6. A sodium polytungstate aqueous solution (sample 3) was prepared by adding sulfuric acid to sample 1 for adjustment to a pH of 6. Further, WO3 concentration (hereinafter, the “WO3 concentration” will be referred to as “W concentration” unless otherwise stated) of each of the sodium polytungstate aqueous solutions of sample 2 and sample 3 having been through the pH adjustments was adjusted to 70 g/L (70 g of WO3 was contained per liter of the sodium polytungstate aqueous solution).

Provenance & Evidence