Page 58 - Application Handbook - TOC
P. 58

SCA-130-503



            The conversion of the nitrogen containing           Subsequently, the gas mixture enters the
            compounds takes place via combustion in an          chemiluminescence detector, connected in
            oxygen atmosphere higher than 700 °C to             series, where the nitrogen content is
            nitrogen oxide, which reacts with  ozone to         determined (See Figure below).
            activated nitrogen dioxide (NO 2*). In the
            subsequent reaction to NO 2, light quanta are
            emitted    (chemiluminescence)     that   are
            measured by the detector.

            ■ Simultaneous TN determination using
            the TNM-L
            Based on the similar oxidation process, the
            TN b determination can be carried out
            simultaneously with the TOC  measurement.
            For this application,  the TNM-L option is
            installed  on the top  of the main TOC-L
            system.


















                                                                      Fig. Simultaneous TOC/TN-Determination

                                                                It should be noted that an optimal injection
                                                                volume    must    be    selected   for  both

                     Fig. TOC-L CSH with TNM-L Modul            parameters.

            The benefit is that no additional  laboratory       ■ Recommended Analyzer / Configuration
            space is required.
                                                                TOC-L  CXX with TNM-L
            For the simultaneous determination, the             ASI-L
            sample is injected onto the catalyst at 720 °C.
            All carbon  atoms present in the sample are
            converted to CO 2 and, in parallel, the nitrogen
            atoms to NO. The gas mixture is then
            transported by the carrier gas stream through
            the NDIR detector, where the carbon dioxide
            content is measured.
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