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EDTA wsate treatment ??

EDTA wsate treatment ??

EDTA wsate treatment ??

(OP)
Lady and gentlemen,

If anyone have the experience to treat the EDTA waste by The thermal hydrolysis technology  ?? We want to destroy completely the EDTA waste (about 4000 mgr/l) by The thermal hydrolysis, what is the optimal condition ? I will appreciate if someone can share with us this experience.

Thanks

RE: EDTA wsate treatment ??

Why do you want to destroy the EDTA?
Is it complexed with hazardous metal cations?

EDTA is most commonly destroyed using hypochlorite at pH 10.
Other methods (ozone, hydrogen peroxide + UV, anodic oxidation) are all slower, more complex and expensive.
I'm sure that heating would speed up all of these methods, and adding an oxidizer would lower the necessary T & P for thermal hydrolysis.

see pp. 247-254 in Handbook of Effluent Treatment and Recycling for the Metal Finishing Industry, 2nd Edn., L. Hartinger, Finishing Publications Ltd. and ASM International (1994).
http://www.asminternational.org/Template.cfm?Section=ClearanceProducts&Template=Ecommerce/ProductDisplay.cfm&ProductID=10819

RE: EDTA wsate treatment ??

(OP)
Hi Kinvlach,

Tks for your feedback, our EDTA wastes is EDTA-Ni, it is very stable ! the pilot test was ran at difference conditions (pH, oxidation (H2O2) thermal hydrolyze (high T&P), the complex EDTA-Ni was not be destroy !

JeffR

RE: EDTA wsate treatment ??

I know that H2O2 doesn't work at ambient conditions, but hypochlorite does. I use an excess, don't measure, just dose according to ORP reading. Also, I have another chelator present, ammonia, so lots of foaming at first & can observe color change to plain green [can even overdose with hypo to get blackish NiO!].
Good luck.

RE: EDTA wsate treatment ??

Another oxidizer that works (& isn't mentioned in wastewater treatment books) is nitric acid. I use it in the form of spent passivation or plating stripping solution.  Adding a little H2O2 rejuvenates some of the spent nitric (converts nitrate back to nitric).

RE: EDTA wsate treatment ??

(OP)
Thanks you Kenvlach for the recommandation ! I will try it

Regards

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