Australia's Science Forum

Another question that seems silly but is important to get right!

I inherited 2 broken mercury thermometers. They are in sealed bags with mercury decontaminant/sulfur but I would prefer that they get disposed of rather than living in my chem store. I assume I can't just throw them away. What is the best way of getting rid of them?

Sarah

CSIS recommends covering droplets of Hg with S to form harmless HgS. So I guess bin it is OK.
Any other ideas?
Lada

Thanks Lada!

DO not throw it in the bin, mercuric II) sulfide is Class 6.1
Place collected mercury in unbreakable sealed container, include in the next hazardous waste collection schedule. Sodium thiosulfate can be added to the mercury in the container whilst awaiting collection for disposal.

I agree, keep for chemical collection.

What does the sodium thiosulfate do if you have already combined the sulfur with the mercury to stabilise it?
Lyn.

Ok…. after even more confusion I went to the governments environment website and found this….

http://www.environment.nsw.gov.au/asken ... Id=AEL-116

You are right, it is not necessary. since you should to put twice as much sulfur as you have mercury I just add little bit of sodium thiosulfate as additional source of sulfur, just in case

Sarah,
does it mean to "bin it"?
Lada

Domestic waste to me means "bin it". It goes against my natural instinct but its on a government website so I assume it's right?

Then again… who knows if the government knows anything about how to look after the environment. But thats a whole can of worms I don't want to open!

"Disposal
Mercury that cannot be neutralised by sulphur powder or is stored in a jar is a hazardous waste and can only be disposed at a household chemical cleanout.
Contact Environment Line
By phone: 131 555
By email: info@environment.nsw.gov.au"

where do you see bin it?

Steps to clean up a spill
Tip: Mercury can move a long way on a smooth flat surface and shatter into tiny balls - check the entire room carefully. Use a piece of paper or light cardboard to collect larger blobs and put these on a wet paper towel then put this into a sealed container. Use an eyedropper or heavy duty tape to pick up any tiny spheres. Use the sulphur neutralising process on these as outlined.

have all people and pets leave, then ventilate the room (continue to do so for 24 hours)
put on heavy duty rubber gloves and pick up any shards of glass, wrap these in a paper towel and seal it in a zip-lock bag
darken the room and use a torch to find all the mercury - it will shine in the light
apply sulphur powder (available at pharmacies) and sprinkle on twice the amount of the mercury spill - the sulphur will neutralise the mercury and make it easier to clean up
leave the sulphur on the mercury for 30 minutes to give it time to neutralise the mercury (do not leave it longer as the sulphur will oxidize into harmful sulphur dioxide)
collect the mercury-sulphur and put it in a plastic bag - use a small brush such as a cheap artists' bristle brush to sweep it up
add another neutral powder to the site to absorb any residual sulphur-mercury (e.g. powdered diatomaceous earth, ordinary baking flour or cornflour)
collect by brush a second time, then discard the brush and gloves in a plastic bag
put the mercury-sulphur and all other paraphernalia into the domestic waste (in plastic bag)
if the mercury has spilt onto carpet, clothing or upholstery, the contaminated part needs to be removed and disposed of.

Yes, I agree, it goes against everything we know, but I too, read it as" bin it" after it has been neutralized with sulfur.
Lada

I use a mercury spill kit, and then save it for chem pick up, I don't put any heavy metals or toxic ones into the general waste.