use of electrolysis to remove salt (1 Viewer)

[bobbie212]

when removing salt from artefacts by electrolysis, does the artefact have to be metal
?

oh yea, and during the electrolysis of a metal artefact, how are the concretions removed?

 

[tennille]

Yeah, I'm pretty sure it has to be otherwise the artefact will be damaged. If it is made of wood, I think you use a PEG polymer to preserve it. There is athing called electrophoresis where the artefact is placed between a positive and negative electrode which attract any particles out of the artefact to the electrode surfaces. That is used for organic materials and therefore wood.

 

[tennille]

Concretions are removed by placing them in dilute acid, especially CaCO3 deposits.

CaCO3 (s) + 2H+ (aq) ---> Ca2+ (aq) + H2O (l) + CO2 (g)

 

[tennille]

I forgot to mention that 1mol/ L of HCL is used, but sometimes an acetic acid- sodium acetate buffer is preferred (pH 3 to 5) in order to stop the CO2 gas produced becoming too vigorous.

You can also remove crusty deposits mechanically with a hammer.

 

[chemicalace]

my chem teacher sucked, she was away for 10+ lessons when we were supposed to be doing shipwrecks so im screwed for the topic *winge*

 

[Xayma]

Concretions are removed by placing them in dilute acid, especially CaCO3 deposits.

CaCO3 (s) + 2H+ (aq) ---> Ca2+ (aq) + H2O (l) + CO2 (g)

They are mainly removed by physical means before using a dilute acid.