Mercury Contamination / Cleaning

[QAFitz]

I've seen where a solution of Calcium Polysulfide (sometimes refered to as Lime Sulfur) can be used to clean any mercury off of a mercury contaminated item. Does any body have any experience with this?
We do some work with the US Gov (Army/Navy etc.) and they are keen on "mercury free" certifications. We are trying to develop an in-house method to clean items - metal hardware, fasteners/pins/shafts etc. - so we don't have to constantly go back to the vendor and his vendor (ad nauseum) to get mercury free statements. We'd like to clean in-house by soaking and rinsing. Any thoughts/comments would be appreciated.

Was posted in Metals & Metalurgy w/no responses.

 

[Goahead]

You may wish to see

http://www.epa.gov/mercury/disposal.htm

and linked documents.

Regards,

http://www.welding-advisers.com/

 

[kenvlach]

Re possible "mercury contaminated item."

About the only way to remove mercury from metal objects is vacuum arc melting. Or, dissolution in hydrochloric acid followed by electroplating out the mercury.

Fortunately, metals are nearly all covered with a thin film of oxide which prevents contamination by any brief encounter with mercury. Just don't use gold tooling with mercury around.

As for in-house cleaning, acid pickling or nitric acid passivation would dissolve and remove any mercury sitting atop the metal's oxide film. But, this would generate a mercury-containing hazardous waste.
Sulfur powder and calcium polysulfide are for spills.

Basically, a lot of paperwork for nothing.