I am afraid that small scale copper business ain´t gonna cut the initial costs, if you factor in your actual time working on the setup and price of feed copper + some at least basic analysis to back your claimed purity. That is why we actually refine precious metals, not zinc or copper.
But having working atomizer, you can make various atomized powders of metals or even alloys. That may be better approach. But I would start it just as hobby with no bigger expectations. Small scale business in your past time, selling cheap stuff is not the profitable area today. Maybe silver alloys would make some sense, some solder alloys powders could potentially have some uses...
To be honest, even I won´t be much interested into it (copper), despite the fact that my 13k yearly salary would be considered a joke in the US
And making some money with side hustle would make much more sense here, where costs are lower and relative cost of work too.
I tried many things. One of them was that I once considered selling powdered tin here (I had few kilos, then I "accidentally" acquired even more). But there was no way of making it viable without huge investment of my time into the thing. Could be done, of course, and I am pretty confident that I will be capable of doing this. But for few hundreds ? Not worth my time. I sold the tin directly as it was, made some OK profit, and moved on.
