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  for Metal Finishing since 1989
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Tests for Concentration Aluminium in Liquids

Dear sir/madam,

I am a British student currently studying chemistry at advanced level. As part of our syllabus, a practical investigation is required. I have chosen to study the effects of aluminium on its concentration in water at varying temperatures, etc.

A key part of my study therefore will be chemical tests to determine the concentration of aluminium sulphates etc in the water.

I would appreciate any information you can give me on this e.g titration methods, step-by-step guides etc, quantitative analysis is very important to my results, and if no suitable methods are available I will need to alter my ideas.

Thank-you for you time,

Yours faithfully,

Chris Alderman
- Stoke-on-Trent, Staffordshire, England.
2001

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2001

You didn't say what concentration ranges you are interested in. For low concentrations, most people use something like ICP-AES for metals. For higher concentrations, there is a published book on analysis of plating solutions. I don't remember the name, but you could search on the Internet for it.

Anions are best analyzed using an ion specific electrode.

James Totter, CEF
- Tallahassee, Florida

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2001

As you are studying A-level I would be surprised if one of your teachers or the school library didn't have a copy of Vogel's Textbook of Quantitative Chemical Analysis ⇦[this on on Amazonaffil links] or Vogel's Quantitative Inorganic Analysis [on on Amazonaffil links]. It is usually my first point of call when looking for an analytical method. A warning, it is far too expensive to buy for an A-level student, don't attempt.

Ciaron Murphy
- Britain

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Ed. note: Indeed, students tend to have limited budgets and books are terribly expensive. But if they can settle for very used and quite old, they can follow the links to sometimes find copies for at little as $5 if their library doesn't have it.

Aluminum can be titrated with EDTA or CDTA and the endpoint followed with a calcium or cupric ISE or, titration with lanthanum fluoride using the fluoride ISE as the endpoint detector. This method is well documented with good precision and relatively little sample preparation. ICP and other methods require sophisticated sample prep and high cost per analysis. Check the web for ISE manufacturers. A pH meter can be used for readout.

Dennis Finch
- Sugar Land, Texas
2005