Australia's Science Forum

Can anyone help me with the disposal method of the waste products after this Senior Science prac?

I have beakers of 2M Nitric acid with disolved calcium from the bone in it, what do I do with it?

MSDS says must be disposed of as hazardous waste
CSIS says (I think) bring to pH 8-10 and sewer
the Risk assessment provided just says sewer

its sitting in the fumehood for now because I haven't got a clue, any thoughts?

Yes bring the PH down to about 7 and down sink to waste with lots of water. For acid I use powder Sodium Hydrogen Carbonate, Or better known as Bicarbonate/ Baking soda, shake onto the Nitric acid it will fizzz up, when it stop's fizzing test the PH, and down the sink to waste with lots of water.

Thank you Labbie

follow on question....

the solid/precipitate, what is it and does it go straight in the normal bin?

feeling dopey
Thanks

Yes, solid goes into bin,and acid waste to be neutralised to about pH8 and siaposed down the sink.
Lada

why are you using nitric acid? vinegar do the same trick; less hazardous, easy to dispose

Yes we use vinegar or dilute HCl. Easy and harmless.

There is only two acids that scare me, Nitric & HF Hydroflouric
Never use it unless necessary and always in a fume cabinet
When it reacts it gives off brown fumes that are extremely TOXIC and do permanent damage to lungs
HF if on skin leaves mild redness but penetrates straight to bones and attacks the Calcium

that is an excellent question, what concentration of other acid do you use and does it take the same time?

I am going to raise this with the HT

Thank you for the advice

I use 2M HCl & leave overnight