Page 20 - Application Handbook - TOC
P. 20
SCA-130-201
The integrated ISP sample preparation unit detection limit (0.5µg/L) and excellent
(an 8-position switching valve with syringe reproducibility in the lower ppb range. The
and sparging gas connection) considerably TOC-V WP/WS is therefore highly suitable for
reduces the users’ workload, as the TOC determination in the ultra-trace range.
instrument carries out dilution, acidification
and sparging fully automatically. TOC-V WP Sample measurement
Method: NPOC (3% Acid, 3 min sparge)
Persulfatsol.: 1,5mL
Injection vol.: 20,4 mL
Result: 2,44 ± 0,42 µg/L TOC (NPOC)
Fig. NPOC- Calibration (Blank and 500µg/L)
When using the high sensitivity catalyst, the
detection limit is approximately 4µg/L. In
addition, the combustion technique can be Abb. Peak graphik of TOC-V WP measurement
used in combination with the TNM-L module,
whereby a single injection is sufficient for ■ Conclusions
simultaneous determination of the total bound Both types of instruments with their different
nitrogen. Simultaneous TOC/TN b oxidation methods can be used for TOC
determination is highly suitable for cleaning determination according to the European
validation, as this enables differential Pharmacopoeia. The advantage of the
determination between cleaning agent and combustion method is its high oxidation
product. potential, particularly for samples containing
particulate matter. Moreover, simultaneous
■ TOC-V WP/WS: Wet chemical oxidation TOC/TNb measurements can be carried out,
The key technique of the TOC-V WP/WS leading to a higher information content of the
analyzer is the powerful oxidation via the analysis. The advantage of wet-chemical
combination of sodium persulfate and UV oxidation is its high injection volume, which
oxidation at 80 °C. The TOC-V WP/WS features leads to higher sensitivity and therefore
an automatic reagent preparation function enables high precision measurements in the
that eliminates possible contamination of the lower ppb range.
persulfate solution. This ensures that the
TOC value truly originates from the sample – ■ Recommended analyzer / Configuration
and not from the reagent solution used. The TOC-L CPH with high sensitivity catalyst
large injection volume (up to 20.4 mL) in ASI-L (40ml), External Sparge-Kit.
combination with the highly sensitive NDIR
detector, leads to an extremely low TOC-V WP with ASI-V (40ml)
