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Determination of Nitric acid in Hydrochloric acid

2007

Dear friends

I have a problem. Kindly suggest me a method to quantitatively estimate Nitric acid contents in a solution of about 4% Hydrochloric acid, about 2% Nitric acid & 25% Ferrous chloride.

Thanks
V.K.Vatsa

Vinod K Vatsa
QC Manager - Boisar, Maharashtra, India

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2007

Vinod

You could measure the total amount of nitrate ion by doing ion chromatography on your samples. This wouldn't be a direct measure of the nitric acid, but would at least give you the nitrate.

Having said that you would need to choose a column and eluant that gives you a good separation of the chloride and nitrate.

Terry

Terry Tomt
- Auburn, Washington

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2007

A lower tech way of going about it: boil a sample with Devarda's alloy, under the proper conditions. Then, distill off the resultant ammonia, to which the nitrate will be quantitatively converted. Then, do an acid/base titration on the distillate, with 0.02 N sulfuric acid.

There's a bunch of method references, which I don't have at my fingertips. If you need one, just give a shout and I'll look one up for you.

Dave Wichern
Consultant - The Bronx, New York