TOC, TIC and TC Determination in a Single Instrument
12 Dec 2011The Multi N/C series of catalytic combustion analyzers from Analytik Jena UK provide a versatile platform that can be configured for the fully automatic direct determination of bound carbon (TIC/TOC, TC, NPOC, POC) from liquid, paste or solid samples in a single instrument using the combustion analysis method. The Multi N/C series meets the requirements of DIN-EN, USEPA, ASTM, FDA and USP standards, including DIN EN 13137 for the determination of TOC in waste, sediments and sludge, and DIN EN 1484 and ISO 8245 for the detection of total and dissolved organic carbon in aqueous samples.
Instruments in the range include the Multi N/C 2100, Multi N/C 3100 and Multi N/C UV HS. The novel design provides an extended dynamic range for TOC measurements from 2 ppb up to 30000 ppm without dilution. This allows the systems to be used in applications ranging from trace-level analysis of ultrapure waters to the analysis of drinking, ground and surface waters with medium TOC, or measuring highly contaminated, particulate waste waters.
Direct measurement of solids is also possible with all the models in the range with the addition of the HT 1300 high-temperature solids combustion system. A click of the mouse is all that is required to change between solids and liquids mode.
This HT 1300 solids module provides catalyst-free high temperature combustion in a robust ceramic combustion tube using an additional furnace which is adjustable up to 1,300 °C. Large solid samples of up to 3 g can be accommodated, which allows for solids with low homogeneity. The large dynamic measuring range of the N/C range is particularly suited for the detection of high TOC content (up to 500 mg C absolute) in solids.
High accuracy results are ensured using patented VITA® technology, which automatically determines the retention time of the sample in the analyzer. This not only leads to good accuracy and sensitivity but also excellent repeatability. VITA improves repeatability from typically 5-10% in the 0.5 – 1.0 mg/l range and 3-5% in the 1000 to 5000 mg/l range to 1-2% across the measuring ranges.
In addition, VITA significantly reduces the intervals between calibrations to around 6 months, reducing running costs. Multi N/C series instruments can be calibrated across the entire detection range using a single standard sample, eliminating the need for a large number of standard reference materials.
The multi N/C® series can also be used for non-direct TOC determination of samples such as sediments, soil and lime stone using the so-called suspension method with no special accessories.
This permits two different methods: TOC detection using the so-called direct method and the differential method. Another option for the detection of the TOC in specific matrices (e.g. sediments, soil, lime stone) is the suspension method. Different devices and technologies can be used to detect the parameter TOC in solid samples.