Chemical waste disposal

[ana.santos]

Hi all,
Can anyone share how you segregate your chemical waste solutions for disposal?I wanted to prepare waste bottle containers to keep waste chemical solutions for future collection but I am not sure how to classify or group them accordingly. Which solutions can and cannot be mixed? I used to have only organic and inorganic containers mixing everything in there.Not sure if this is safe.
Thanks for any advise.

Ana

[Labbie]

Our Silver waste has a jar with a label.
Add Sodium chloride solution of any conc, to bottle, when settled clear top can go down the sink to waste. A small silver salt will remain on the bottom.
From the CSIS

Lead Waste: Add sodium carbonate solid, to waste, pour into bottle, when clear on top, pour clear down the sink to waste.
A small lead salt will remain on the bottom.
From CSIS

Barium Waste: Add sodium carbonate, sitr & Pour the mixture into the waste jar of Barium. WHen settled, the clear solutin may be decanted & washed down the sink.
Again from CSIS.

I keep these when they are full, for colleciton.
Copper sulfate goes around and around, left in the flume cupboard they go back to crystals.

[smiley]

Hey Guys,

Not being DET I don't have access to CSIS. I need to give some Seniors a definitive answer on the right way to dispose of Zinc Nitrate, Copper Nitrate, and Nickel Chloride. We all know that pouring it down the sink is the wrong answer, but are there any neutralizing techniques that could be used, rather than merely jugging it up for a Waste Removal company? We tried the steel wool-in-the-copper trick, but it doesn't work for Cu(NO3)2 :( One of my issues is that the darlings are diluting great quantities of it down to 0.025M, so I don't really want to pay a company to remove large amounts of water, per se.

[lada]

Hi Smiley,
NiCL2 solution can be disposed down the sink at rate of 1.4L per day of 0.1M solution (or 8g of NiCL2 per day) after adjusting pH to 8 .
I just realised this is Sydney water specifications, may not be relevant in your area.

The same with Zn and Cu nitrates. Ajust pH to 8 and you can dispose down the sink at rate of 4g per day or 0.6L of 0.1M Zn(NO3)2solution and 4g or 1.4L of 0.1M cu(NO3)2.
You might need to find out limits of heavy metals in your area.
Lada

[RosalieM]

Can't you just evaporate some of the water off? Put it in the fume cupboard on a hot plate stirrer for a while? That's pretty much what I do with copper sulfate (yes, I realise they are different chemicals, but surely at that low concentration you could get a fair bit of water off without boiling it dry?) This is by no means a 'scientific' answer. Just me thinking...