Model 6700

​The Series 6700 covers a complete range of Total Organic Carbon (TOC) Analyzers capable of addressing a variety of industrial applications for process and environmental compliance purposes.

TOC Methods​

UV / Heated Persulfate Method

Excellent TOC accuracy from low parts per million (ppm) to moderate concentrations of salt-free samples. It requires minimum maintenance and is the preferred method for mostapplications.

Combustion Method

Good for difficult to oxidize or high TOC concentration samples with industrial salts less than 1%. It is the preferred method for some higher range samples, which have limited oxidation efficiency by other methods.

Ozone / Hydroxyl Radical Method

Excellent for low to high levels of TOC analysis for difficult to oxidize samples or in undiluted acids or industrial salts over 26%. It is low maintenance and is the preferredsubstitute for High Temperature Combustion in most applications.

Ultrapure Method

Unsurpassed NDIR detection for interference-free accuracy in the parts per billion (ppb) range. Requires no pumps for minimum maintenance, has the lowest MDL and is preferred for applications less than 1,000 ppb TOC.

Operational Theory

Selecting the appropriate TOC method for an application requires a cost / performance trade-off analysis. To perform correct TOCanalysiss, the operator must measure all constituents of organic carbon present in the sample: Non-Purgeable Organic Compound (NPOC) and Purgable Organic  Carbon (POC). It must also exclude the TIC interference.

TOC Direct

TOC Direct is a basic, commonly used technique to measure the NPOC. Acid is added to the sample,lowering its pH to approximately 2.0, at which point the carbonates present in the sample are converted to dissolved CO₂. In the sparger, the carrier gas strips (sparges) the CO₂ converted from the TIC and vents it, along with any purgeable (volatile) organics, leaving only NPOC in the sample. The resultant NPOC is then oxidized to CO₂ in the reactor and measured by the CO₂ detector as NPOC in the sample, often referred to and reported erroneously as TOC.

TOC True

The sample system is designed to accept the liquid sample and any required reagents, transporting them through the analyzer to the appropriate components. For TOC (actually, NPOC) analysis, the sample is pumped initially to the sparger, where it is mixed with acid to lower the pH between 2.0 and 3.0. At that pH, all inorganic carbon / carbonates are converted to dissolved CO₂ gas, which is sparged out of the liquid solution by the air / O₂ carrier gas. At this point, any volatile organic carbon is also sparged out and lost for inclusion in the TOC analysis, unless a TOC Direct analysis is performed.

Configurations

Teledyne offers custom turn-key system solutions suitable for general purpose or hazardous, outdoor environments, complete with sample systems, oxygen generators and NEMA enclosures.

Installation Requirements