4 ms·

When we extract ore from a given area, it's mixed with just a few different compounds. So you tailor various acids and processes to economically filter out just

by coryrc 5y ago

When we extract ore from a given area, it's mixed with just a few different compounds. So you tailor various acids and processes to economically filter out just want you need. How do you plan to do this when you have every compound we've ever created with overlapping solubilities and you want pure output?

kragen 5y ago
> When we extract ore from a given area, it's mixed with just a few different compounds. This is pretty far from the truth. Rock is less chemically complex than living plants, animals, and fungi, it's true; but there's a long distance from "less than hundreds of millions" to "just a few". The article explains how it's done in the case of lithium-ion batteries. It is true that to the extent that you can reduce the admixture of other materials, you can reduce the costs. > How do you plan to do this The standard mining methods include roasting, oxidation, and reduction (pyrometallurgy); froth flotation; lixiviation; defecation; crushing and grinding (milling or comminution); screening; and agglomeration. More exotic methods, some of which are crucial to one or another method, include vacuum sublimation, electrolysis (molten-salt or aqueous), amalgamation, recrystallization, and fractional distillation. There are also processes that don't fit neatly into one of these categories, such as the Pidgeon process. There's a good outline at https://en.wikipedia.org/wiki/Template:Extractive_metallurgy https://en.wikipedia.org/wiki/Template:Extractive_metallurgy.
- coryrc 5y ago
  My comment was in reply to mining trash dumps. Batteries obviously have a small (-ish) set of possible compounds and it should be economically feasible to recycle used batteries once there is sufficient volume that needs to be recycled. (I guess we're still at least a decade away but that remains to be seen... if it's sufficiently efficient, it could be cheaper to recycle than reuse older batteries).
  - kragen 5y ago
    Yeah, I was saying you can use the same processes for mining trash dumps that you use for mining natural rock. Maybe there are more economically productive techniques specific to mining trash dumps (computer vision with conveyor belts, desoldering electronic components, deshredding correspondence to blackmail politicians with) but the usual rock-processing techniques form a minimal baseline. If you heat anything up enough it becomes rock again. (And gaseous oxides like those of carbon and sulfur.)

by coryrc 5y ago

kragen 5y ago

> When we extract ore from a given area, it's mixed with just a few different compounds. This is pretty far from the truth. Rock is less chemically complex than living plants, animals, and fungi, it's true; but there's a long distance from "less than hundreds of millions" to "just a few". The article explains how it's done in the case of lithium-ion batteries. It is true that to the extent that you can reduce the admixture of other materials, you can reduce the costs. > How do you plan to do this The standard mining methods include roasting, oxidation, and reduction (pyrometallurgy); froth flotation; lixiviation; defecation; crushing and grinding (milling or comminution); screening; and agglomeration. More exotic methods, some of which are crucial to one or another method, include vacuum sublimation, electrolysis (molten-salt or aqueous), amalgamation, recrystallization, and fractional distillation. There are also processes that don't fit neatly into one of these categories, such as the Pidgeon process. There's a good outline at https://en.wikipedia.org/wiki/Template:Extractive_metallurgy https://en.wikipedia.org/wiki/Template:Extractive_metallurgy.

coryrc 5y ago
My comment was in reply to mining trash dumps. Batteries obviously have a small (-ish) set of possible compounds and it should be economically feasible to recycle used batteries once there is sufficient volume that needs to be recycled. (I guess we're still at least a decade away but that remains to be seen... if it's sufficiently efficient, it could be cheaper to recycle than reuse older batteries).
- kragen 5y ago
  Yeah, I was saying you can use the same processes for mining trash dumps that you use for mining natural rock. Maybe there are more economically productive techniques specific to mining trash dumps (computer vision with conveyor belts, desoldering electronic components, deshredding correspondence to blackmail politicians with) but the usual rock-processing techniques form a minimal baseline. If you heat anything up enough it becomes rock again. (And gaseous oxides like those of carbon and sulfur.)