Laboratory products
The detection of minute TOC and TNb content in salty matrices, such as seawater, poses a special challenge for many TOC analysers with thermocatalytic digestion. Why? Due to the high salt content with simultaneously low analyte concentrations the sample can often not be diluted meaningfully. In addition the reactor of the TOC/TNb device is continually loaded with sodium chloride and other salts with every sample injection. With increasing load on the catalyst the measuring results display significantly reduced recovery rates and increased measured value variations. The salt accumulating in the system also rapidly leads to the catalyst and other consumables of the combustion tube becoming useless and having to be replaced after a short period of time.
That there are alternatives is demonstrated by the measurements of deep sea water samples using a device of the multi N/C® series shown below.