How to neutralize water containing Lithium by-product with High PH
January 24, 2012Q. Hi,
I would like to know if there is a way for me to self treat water that has been in contact with lithium where small amounts of lithium are stuck on tooling.
We work with Lithium and do some pressing and other proprietary work with it.
Our end product is for thin films coating, so lubricants (such as oils) are out of question, (Just so we don't start with that as an answer option)
The Lithium metal particles and smears, that get stuck on the mold and other tooling at times have been removed using water to react and disolve it.
The pH is about 12 in the lithium rinse water we had tested, but that was just one sample and the pH in others could , I believe could be much higher.
My Question Is; Is there a way to neutralize the water so that it can go down the city drain or into our storm drain pond with no harmfull effects?
We contain it for Hazardous waste disposal at this time.
We would also be interested in talking to and possibly hiring a consultant if needed.
Thanks in advance for your replies.
Regards,
Paul Carter
Procurement / Estimating / R&D - Biddeford, Maine, USA
I would check with your local regulations for Li limits in the waste water that you discharge. I know that isn't entirely helpful but that would be where I'd start.
Were you wanting to precipitate the Li out of the water or just neutralize the pH?
If only to neutralize the pH a little acid should do the trick. Initially I was going to recommend HCl but a quick search did not yield a good answer. However, given that the Li is in dissolved in water in ion form and not solid it might be alright. HNO3 did not show the same reaction to Li but again I am not certain.
I would perform a lab bench test just to be certain that there is not a reaction. Always add acid to water and slowly. If you had some spent acid on site or some diluted acid that should work too.
Perhaps another chemist could shine some more light on this.
- Savannah, Georgia, USA
January 30, 2012
Thanks very much for your reply.
Since the posting I have talked with our Haz waste company and we are also in touch with our towns wastewater management.
As it turns out, waste water with a pH of >12.5 has to be
considered as hazardous waste and to neutralize it at that point requires a permit to do so.
We have not reached that high pH yet, but we would like to
have someone do the Lithium stripping for us. So, now I am looking for a company that can strip Lithium from stainless steel and copper backing plates and and send the cleaned backing plates back to us.
I've sort of changed my question now, so I'm not sure how many people will read this.
Thanks again,
Paul
- Biddeford
