Abstract: The disposing of the tannin-germanium slag, which was obtained during tannin-germanium precipitation process, was studied. The separation of tannin and germanium can be achieved by successively slurrying the tannin-germanium slag, complexation with oxalic acid and adjusting the pH value of the suspension to 8-9 with 10 % aqueous sodium hydroxide. The germanium salt is removed by centrifugal separation, and the aqueous tannin solution can be reused to extract germanium. The result shows that recovery rate of tannin can reach 50 %. Using 28 times of tannin as much as germanium, the recovery rate of germanium can be 98 %.

Key words: tannin, tannin-germanium slag, recycling, oxalic acid, sodium hydroxide