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Titanium analysis wet-titration method
Does anyone know of a procedure for the manual titration of titanium metal dissolved in a solution of hydrofluoric acid / Ferric Sulphate?Nigel Gill, B.Sc MIMF AIEMA MRSC
Aerospace - Glasgow, South Lanarkshire, Scotland
I don't know of any titration for dissolved titanium. You could do it colorimetrically by taking a small sample of bath, adding some (say 20 ml)1:1 sulfuric acid, and heating strongly, in a fume hood of course, to white fumes. This is to drive off the fluoride as HF. Now, let the mixture cool, add it to about 400 ml water in a 500 ml volumetric flask, let this cool, then make up to the mark with water. Now take out a 10 ml portion, and add 1 ml of 3% hydrogen peroxide. A yellow color will develop, the intensity of which is proportional to the concentration of titanium. By comparing with standards made up in a similar way, you can get to the answer.
This would be a lot of work to set up, but once you do the initial work, routine analyses shouldn't take too long.
- The Bronx, New York
January 19, 2009
Does anyone know of a manual titration for the determination of dissolved titanium generated from an etch tank?
Aerospace. - Glasgow, Scotland
January 23, 2009
Aerospace - Yeovil, Somerset, UK
Textbook of Quantitative Inorganic Analysis
January 25, 2009
I stay with Dave that there is no known titration for titanium, maybe there is an indirect method.
A colorimetric determination is still a good idea. Also you can use the density of the solution to analyse the titanium content.
Why do you want a time consumption titration method?
- Brilon, Germany, EU
January 29, 2009
The problem with cations like Al3+ and Ti4+ is that they are very easily hydrolysed.
If you're determined on titration, you might have luck adding a known excess of EDTA at a low pH, stirring for ten minutes, then raising the pH to 10 and back titrating to a pink Eriochrome T endpoint with a standardized Zn2+ or Mg2+ solution.
Take a look at Meites'"Handbook of Analytical Chemistry" [link is to info about book on Amazon].
- The Bronx, New York
July 12, 2010
To ask a follow up question, we are currently looking into in-house methods to test our Dissolved Ti Concentration and I was wondering if there is a standard method that I am not aware of. We do Titanium etching using NHO3 and HF. From what I have found through research so far, Daves colorimetrically is the only one that would work and test Ti directly. Density may work, but in my mind it is also dependent on other metals that have been etched, so we would have to go back and look at all the compositions of the different Ti alloys we have etched and calculate it out.
- Corvallis, Oregon, US