High Temperature Method for Reliable Online Water Analysis Technology

Total Organic Carbon (TOC) is a measure of the amount of carbon-containing organic compounds present in water. High-temperature methods for detecting TOC in water involve the complete oxidation of organic compounds in a water sample at high temperatures, followed by the measurement of the resulting carbon dioxide (CO2) released.

The high-temperature method typically involves the following steps:

1. Acidification: The water sample is acidified with sulfuric acid to convert all inorganic carbon (e.g., dissolved carbon dioxide) into carbonic acid.

2. Purge: The sample is then purged with a stream of pure oxygen gas, which removes any dissolved carbon dioxide.

3. Combustion: The remaining organic carbon in the sample is then completely oxidized to carbon dioxide by heating the sample to a high temperature (typically 680 to 800°C) in the presence of a catalyst, such as platinum.

4. Detection: The resulting carbon dioxide is then measured using a non-dispersive infrared (NDIR) detector or other sensitive carbon dioxide sensor.

Our LAR™ water quality analyzers use a high temperature method of 1,200°C, can completely oxidize a sample to accurately determine sum parameters – particularly when measuring the TRUE TOC with differing of concentrations.  LAR is your solution for the determination of parameters such as TOC, TNb, TOD, COD, BOD and toxicity.   We are the only company worldwide that, using a high temperature method of 1,200°C, can completely oxidize a sample to accurately determine sum parameters. Particularly when measuring the TRUE TOC with differing of concentrations.  

For an exact TOC measurement, all carbon bonds must be reliably combusted. Using a temperature of 1,200°C, we have developed a high temperature method which makes this possible! This temperature was chosen due to the proven fact that a complete oxidation of a sample cannot occur at temperatures below it. For example, the carbon bonds of carbonates only break fully when reaching a combustion temperature of 1,200°C. Basically, the lower temperatures deliver less exact measurement results. For this reason, we describe this as TRUE TOC.  Because of our high temperature capability, our analyzers do not require any catalysts. Catalysts are only necessary for the low temperature catalystic “high temperature” oxidation (680 – 1,100°C) to support the oxidization of the carbon bonds. However, the performance of the catalysts is lowered over time. This affects the measurement, necessitates continual new calibration, and eventually requires that the catalysts be replaced.