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Effluent treatment of TiN stripping solution

we strip off TiN coating from still parts. the solution we use comprise water, H2O2,and some other basic chemicals. pH of the solution is maintained at 7/8. we want to know how to treat the waste solution before disposal. is it possible to separate the chemicals as solid and separate water. please suggest.

P.G. Ray
coating - Kolkata, India
June 22, 2009

Not many places have limits for titanium and I am not aware of any limits for nitrides as nitrides. What limits are you trying to meet? How can we help without that knowledge or what all of your chemicals and in what form are used. Do you know what the chemical reaction is for the strip process. IE: what is formed.

James Watts
- Navarre, Florida
June 24, 2009

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August 6, 2009

I am always struggling to keep titanium in solution for the research I do, and here you are trying to get it out of solution. :)

Knowing the H2O2 is not the chemical of concern in this case - the peroxide is used to generate oxides to exchange with the nitrogen. At your pH, this will form TiO2, an insoluble complex, unless other ions are present to stabilize it. I'm hoping fluoride or sulphate. What color is the solution after the TiN has been stripped?

In this situation, increasing the pH to >11 with some caustic soda [affil links] will form sodium titanate, an insoluble complex at room temperature.

RH Kinner
- Toledo, Ohio