Materials Science · Hydrometallurgy

Tellurium Recovery from Copper Anode Slime

Copper anode slimes carry the tellurium and selenium that tagged along with the copper ore — as Cu₂Te and Cu₂Se. An alkaline oxidative leach dissolves both as tellurite (TeO₃²⁻) and selenite (SeO₃²⁻), but Se dissolves faster and less selectively than Te. Tune the caustic (NaOH) dose, the oxidant dose, and the feed's selenium load, and watch the leach liquor's Te purity rise or collapse.

Reactor idle
pH — Eh — mV t 0.0 h
Te extraction—into liquor as TeO₃²⁻
Liquor Te selectivity—vs. co-dissolved Se
Te lost to residue—unleached, reports to tailings

🧪 Tellurium Recovery from Copper Anode Slime

Copper anode slime carries the tellurium and selenium that hitchhiked with the ore as Cu₂Te and Cu₂Se. An alkaline oxidative leach dissolves both into the liquor as tellurite and selenite ions — but selenium is the more reactive chalcogen and tends to win the race for the available oxidant, diluting the tellurium purity you actually want.

🔬 What It Demonstrates

Pseudo-first-order leach kinetics for two competing chalcogenide species, with Te dissolution favoured by high pH (a more stable tellurite complex) and Se dissolution dominated by oxidant availability — the real basis for Te/Se separation in copper-refinery byproduct processing.

🎮 How to Use

Raise the NaOH dose to push pH up and favour tellurium selectivity; raise the oxidant dose to speed up leaching overall (it helps both species, so it mainly shortens the batch rather than improving selectivity); increase the feed's selenium share to see how a dirtier feed drags liquor purity down even at the same process settings. Watch the pH/Eh readout and the reactor's liquor color and tracer particles track the live chemistry.

💡 Did You Know?

Copper anode slime is one of the world's main commercial sources of both tellurium and selenium — byproducts of refining copper that would otherwise be discarded, now critical inputs for CdTe solar panels and selenium rectifiers.