TOC Analyzer

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Venugopal Narne
Venugopal Narne's picture
TOC Analyzer

Hi,
Can anybody help me by sugesting a good TOC Analyzer, my application is to monitor the contaminants from surfaces of manufacturing sites measurement has to do before expose to surface and then after exposure to surface and measuring the difference betweem these two measurements, i am in india (consignment need to be deliver to India) i can effort more amount i need advaced equipment with auto sampler, please provide me the details

Dr. Analytical
Dr. Analytical's picture
I work with a laboratory that

I work with a laboratory that uses a Sievers Model 800, with an Automatic Sampler.   It generally works well, but needs regular maintenance and calilbration, like all measuring instruments.  The current instrument is the 900 series.
The company is now called GE Instruments, and they do have a representative in India.
http://www.geinstruments.com/ionics/india/india_main.html
 

Greg Pronger
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Before purchasing, ensure that the unit you purchase meets the type of measurement that you'll be performing. When measuring TOC, typically we are converting carbon in the sample into CO2 and then measuring the CO2 via NDIR. Now besides ensuring that the overall functionality of the system meets your needs (autosampler, soil capability, etc) there are two main approaches to oxidize the available carbon, one being simple combustion and the other using persulfate-UV oxidation.
For most applications, the determining factor is sensitivity. Original TOC systems were combustion units, and to a large extent when the persulfate-UV instruments came out, due to significant improvements in sensitivity, a large portion of the instruments sold became the newer style. Recently though, the combustion units have become on par regarding sensitivity (though I suspect if ultimate sensitivity is your goal the persulfate gets the nod). However, if you are analyzing surface waters, which are likely to have a significant contribution of TOC from humic acids, the combustion unit will likely give you better analytical results. It seems that humic acid is either precipitating within the persulfate systems or is simply too stable to be have quantitative oxidation under the instrumental conditions. In this scenario, the combustion unit would be your better option.
 
We are using a Shimadzu 5000 (purchased from a used equipment reseller) with an autosampler as well as a solids module and have been satisfied with the systems performance.
 
Sincerely,
Greg Pronger

Deuterium
Deuterium's picture
 Hi,

 Hi,
I am interested in purchasing a TOC analyser for liquid samples. I would also like to determine TNb and I see that three types of detectors are available for N detection: (i) NDIR (ii) Chemiluminescence and (iii) electrochemical cell detector. Can anyone help me with identifying the pros and cons of these detectors for N detection with respect to (i) sensitivity (ii) stability and reproducibility (iii) range of detection (iv) ruggedness.
Thanks

janusstrong
janusstrong's picture
There are some articles on

There are some articles on TOC Analyzer which I've wrote. Hope you find them useful.

HFExAssociate
HFExAssociate's picture
Hello, I would like to ask a

Hello, I would like to ask a few questions about TOC analysis:
1. How many measurements do you perform for each sample? Only one or more?
2. Do you use disposable bottles for samples or do you have bottles for repeated use, which are washed properly?
3. What kind of tests do you perform in order to verify the accuracy of your TOC analyzer and how often do you perform them? Daily,weekly, monthly, every 6 months?