Behavior of tannins in germanium recovery by tannin process

The behavior of tannins in complexation with various metal ions was investigated to understand the complexation process of germanium, to reduce tannins use, and to improve the germanium recovery as a byproduct in zinc metallurgy. The experimental results obtained show that metal ions with relatively high valence (e.g. Fe3+) and big ionic radius (e.g. Pb2+) bind strongly to tannins, and that utilization of the tannins can be improved greatly by re-use and multi-use.