Page 37 - Application Handbook - TOC
P. 37

SCA-130-305



            ■ Kit for high salt samples                            10
                                                                   9
            For the determination, a TOC-L CPH was
            equipped with a kit for high salt loads. The kit       6
            consists of a special catalyst tube, a special        Signal[mV]
            mixture of various catalyst beads and a                3
            ceramics  grid, which replaces the platinum            0
            net.                                                   -1  0           5             10
                                                                                               Zeit[min]

                                                                  Fig. Example peaks of 50% sodium hydroxide
                                                                                   solution




















                                                                ■ Recommended Analyzer / Configuration

            When using the high-salt kit, sample                TOC-L  CPH
            acidification is carried  out with sulfuric acid,   OCT-L (8-port samples)
            which is used here to modify the sample             High-Salt-Kit
            matrix. Compared to NaCl with a melting             B-Type-Scrubber
            point of 801 °C, the melting point of NaSO 4 is
            higher (881 °C) which extends the lifetime of
            the combustion tube.


            ■ Results
            The 5% sodium hydroxide can now be
            measured using the  NPOC method. The
            duplicate  determination of the sodium
            hydroxide yielded the following results.

                 Sample             NPOC           RSD
                                    [mg/l]          [%]
            Sodium hydroxide      <10 (8,2)          -
            (50%)
            Sodium hydroxide
            (50%)                 <10 (8,3)          -

            The sodium hydroxide met the required purity
            criteria of < 10 mg/L TOC.
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