i am working in lab, and i need to quantifiy the concentration of sodium and calcium in a soil solution sample, and i don't have an atomic spectroscometer , so is it feasible to do this kind of measurement using UV-Visible spectroscometer.
Dear Louadj,
It is very common to measure these cations by the use of a UV/Visible spectrophotometer. Samples should be pre-treated with derivatising agent/s, prior to having their measurements taken at visible wavelengths.
Kind regards,
Ade Kujore
Marketing
Cecil Instruments Limited
Milton Technical Centre, Cambridge CB24 6AZ
United Kingdom
email:- [email protected]
telephone:- +44 (0) 1223 420821
fax.:- +44 (0) 1223 420475
web site:- www.cecilinstruments.com
Dear Ade Kujore ,
thank for your answer , can you give some advice and insight or a paper reference , about the pre-treatment with derivatising agents ?
Dear Louadj,
Chloride ions equivalent to the sodium ions in a sample, may be reacted with mercury thiocyanate, to form mildly dissociated mercury chloride. The thiocyanate released then reacts with iron(III) ions to form iron(III) thiocyanate. This thiocyanate is measured at 550 nm in a Visible spectrophotometer.
At a neutral pH, calcium ions react with phthalein purple to form a violet dye, which is measured at 565 nm in a Visible spectrophotometer. Please be aware that small quantities of Al 3+ and Ni2+ may interfere with this test.
Kind regards,
Ade Kujore
Marketing
Cecil Instruments Limited
Milton Technical Centre, Cambridge CB24 6AZ
United Kingdom
email:- [email protected]
telephone:- +44 (0) 1223 420821
fax.:- +44 (0) 1223 420475
web site:- www.cecilinstruments.com
Thank you dear Abe kujero for your answer and your help. But I have another answer, for the sodium solution , I need to add two compound which are the thiocyanate mercury and a solution that has an iron( III) in it . And for the calcium, how to avoid interference with aluminium and nickel ?
Dear Louadj,
The sodium analysis is a two step process.
If the aluminium or nickel levels do interfere, you may have to selectively extract the calcium, aluminium or nickel.
Have you considered the use of ion chromatography. It is a relatively straightforward technique and does not require the mentioned ions to be extracted or derivatised, and can be relatively inexpensive. In addition, it is a pretty sensitive technique, where sensitivities may be enhanced by the use of an appropriate column/s, sample pre-concentration and the optimum instrument parameters.
Please find attached, an application note which cover an example of the mentioned analytes.
If you do decide to obtain an ion chromatography system, do consider one which is modular, easy to install and use and maintain, and robust. In that way extra modules, such as detectors, autosamplers, post column reactors, etc., may be added at any stage, to accommodate your future requirements.
Kind regards,
Ade Kujore
Marketing
Cecil Instruments Limited
Milton Technical Centre, Cambridge CB24 6AZ
United Kingdom
email:- [email protected]
telephone:- +44 (0) 1223 420821
fax.:- +44 (0) 1223 420475
web site:- www.cecilinstruments.com
Dear Kujero ,
thanks very much indeed for your suggestion, and recommandations.
Kind Regards Louadj Yacine
- Badges
- Science topic
- Similar topics
- Engineering
- Chemical Engineering