Total Organic Carbon


Our Shimadzu TOC-5000A Total Organic Carbon Analyzer and Shimadzu TOC-Vcsh are capable of measuring Total Carbon (TC), Inorganic Carbon (IC), Total Organic Carbon (TOC), and Non-Purgeable Organic Carbon (NPOC). Our detection limits are within 10 parts per billion for low concentration level-high sensitivity analysis. Sample throughput is greatly increased with the addition of the ASI-5000A Auto Sampler. For samples with concentrations greater than 1 part per million, up to 70 samples may be analyzed per day.

Dissolved Carbon Combustion Theory

TC: Sample is combusted to CO2 in a column filled with oxidation catalyst contained in a 680C furnace. The combustion product flows through the IC reaction vessel, cooled and dried by a dehumidifier. The combusted sample is then measured in the sample cell by an infrared gas analyzer.

IC: Sample is introduced into the IC reaction vessel which contains an acidified solution and carrier gas flowing in the form of tiny bubbles. Only the IC component of the sample is decomposed to CO2. IC concentration is then determined using the same procedure as TC concentration described above.

TOC: TOC concentration is calculated by subtracting the IC concentration from the TC concentration.

NPOC: Sample is acidified and sparged with high purity air, eliminating the IC component. Sample is then injected onto the column and combusted to CO2.

The CO2 is detected by an infared gas analyzer which outputs a detection signal (analog) which generates a peak. The area of the peak is proportional to the carbon component of the sample and concentration can be calculated by comparing to standard solution.