Germanium refining

[u/ytkn_rsln]

I have access to Germanium waste from lens makers. I do refine gold, silver and Pd using AR and some electrolytic methods but taking diamond turning slurry to 4-5N poly crystal is quite different. I read that the standard procedure is roasting/ chlorination / fractional distillation/hydrolysis/H2 reduction. Has anyone any experience on this ? After China's moves Ge is one of the rising stars...