IC and AAS vs Colorimetric Techniques for water analysis

[lgchrom]

Theoretically with some good organizational skills, one could manage to streamline their workflow and have a high throughput of anion and cation analysis of water using colorimetric methods. (esp. with kits by Hach , Merck etc)

Ion Chromatography has a higher cost of purchase, but what about running cost compared to colorimetry?

And most important of all, how do the methods compare for the ions? Are there colorimetric methods for ions in water that are simply too problematic to use?

What about the heavy metals? There are kits available that supposedly measure Cd and Pb from 0-40 ppb with nos significant inteferences.

There are also kits for Na and K!!!!

Could you comment please?

Btw in my lab I have UV-Vis, FAAS, GFAAS and IC with EC so I have all options open.

[oscarBAL]

Hi Mario; I think from my experience that IC it cam be more accurate and precice taht colorimetry; bur I would like to know a coulple of things here?

What kind of sample are you running (some waste waters for example have colour that interfere with your reading using colorimetry kits)

How much accuracy you need?

How many samples you going to analyze? in some places where you analyze more that 100 a week operationj cost of colorimetric kits are expencier than IC. To get Reagent in latin america is usually higer price than in United state for example.

For heavy metal cororimetrics kits are suitable only under very good condition; again, depending of your sample and sample treatment; ususally this results are not suitable for regualation porpouses.

Another advantage of IC is that this technique usually generate less hazardous waste or is less pouluting than colorymetri form my poin of view.

AAS you can not analyze anions.

I have working with both technics; first of all how many sample and what kind of sample; what are your needs or the porpouese of the analysis.

Please let us know more about it.

Best Regards.

Oscar.

[lgchrom]

Thank you for your reply Oscar.

I own all 3 kinds of equipment mentioned.

The samples are not more than a 100 per week.

I think that colorimetry is too time consuming for a typical water sample for around 10-12 parameters.

The accuracy needed is the best possible. Usually it is drinking water and sometimes waste water. I also often do soil extracts.

Since I already own the IC I would probably be using it more than the photometer due to its automation.

But I am just curious about the reliability of other labs that use only a colorimeter with kits for monitoring drinking water etc.