Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: chiralSPO on 05/09/2014 23:19:22

Title: alkaline zinc electrowinning
Post by: chiralSPO on 05/09/2014 23:19:22

Is anyone aware of a large-scale hydrometallurgical zinc refinery (anywhere in the world) that  reduces zinc oxide to zinc metal under alkaline (pH > 10) conditions?

I can find patents on the technology, but most are fairly old, and it seems as though reduction of zinc sulfate in sulfuric acid is the preferred method today even though it is less efficient (requires higher voltage than the alkaline version). I think it's because sulfuric acid is often produced on-site as a byproduct of the zinc sulfide ore treatment, so they don't have to buy it. But I wonder if there is any large scale recycling of zinc oxide to zinc (no sulfur involved), which would make more sense under alkaline conditions.

Title: Re: alkaline zinc electrowinning
Post by: Bored chemist on 06/09/2014 18:31:31

I don't know if any factory is doing it, but there's plenty of research about electrowinning from zincate.
https://pooya.um.ac.ir/ResearchDocuments/papers/1012418.pdf

Title: Re: alkaline zinc electrowinning
Post by: chiralSPO on 06/09/2014 19:49:28

Thanks Bored! I am familiar with this paper, and I would like to know if there is a factory doing this. I figured posting here was worth a shot.