Producing Silver (Ag)

Ag: Silver

This element is known from ancient ages.

Abundance: 0.08ppm(in the earth's crust)

Method 1

Add zinc into refined and melted lead, and agitate.

Silver is included in lead ore as minor component.

Ag + Zn AgZn

Recover floating metal on the surface of melt. This metal has higher melting point and lower density.

AgZn

Distillate under vacuum.

AgZn Zn + Ag

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Method 2

Add sodium cyanide under ambient condition to residue of electric smelting such as copper, zinc), and silver sulfide (pyrargyrite), and dissolve silver to the solution.

4Ag + O2 + 8CN(-) + 2H2O 4Ag(CN)2(-) + 4OH(-)

Ag2S + 4CN(-) 2[Ag(CN)2](-) + S(2-)

Ag2Cl + 2CN(-) [Ag(CN)2](-) + Cl(-)

Add zinc powder to the solution.

2[Ag(CN)2(-)] + Zn [Zn(CN)4](2-) + 2Ag

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Method 3

Add alloy of gold and silver such as gold into hot concentrated sulfuric acid, and silver is dissolved into the solution.

2Ag + SO4(2-) + 4H(+) 2Ag(+) + SO2 + 2H2O

Recover silver by electrodialysis of solution, and recover gold from the residue.