Tic & Toc Analysis; Tc Analysis - Hach BioTector B7000 User Manual

4.2.3.1 TIC & TOC Analysis
1. An unfiltered sample is injected into the BioTector reaction chamber (reactor).
2. An acid reagent is added and the oxygen carrier gas flow is activated to remove the inorganic carbon.
The carbon dioxide gas is sparged by the addition of the acid reagent and is carried by the oxygen
carrier gas and measured with a nondispersive infrared (NDIR) CO
as Total Inorganic Carbon (TIC). This reaction phase is called TIC phase.
3. Ozone generator is activated. A base reagent is injected and the sample is then oxidized with
hydroxyl radicals, a strong oxidizing agent, which is generated by exposing high pH reagents to
ozone. This reaction phase is called Base Oxidation phase. The complete oxidation of organic
compounds takes place and carbonates are formed.
4. After the Base Oxidation phase, the carbonates are sparged in the form of carbon dioxide gas by the
addition of an acid reagent. The carbon dioxide gas is carried by the oxygen carrier gas and
measured with the NDIR CO
reaction phase is called TOC phase. The TOC result obtained from the TIC & TOC analysis type
represents the Non-Purgeable Organic Carbon (NPOC).
5. At the end of the reaction, the oxidized sample liquid is discharged from the reactor with increased
oxygen flow.
4.2.3.2

TC Analysis

1. The oxygen carrier gas flow and the ozone generator are activated. Base reagent is injected into the
reactor and hydroxyl radicals are generated by exposing the base reagent to ozone. This reaction
phase is called Pre-Oxidation.
2. The oxygen carrier gas flow is stopped and an unfiltered sample is injected into the reactor of the
BioTector.
3. While there is no carrier gas flow, the volatile organic content of the sample is oxidized with hydroxyl
radicals. This reaction phase is called VOC Oxidation, as the oxidation of volatile matter is achieved
without being sparged.
4. When the VOC Oxidation phase is complete, the oxygen gas flow and the ozone generator is
activated and the remaining Non-Purgeable Organic Carbon (NPOC) content in the sample is
oxidized by the hydroxyl radicals in Base Oxidation phase. The complete oxidation of organic and
inorganic compounds takes place and carbonates are formed.
5. When the oxidation processes are completed, the carbonates are sparged in the form of carbon
dioxide gas by the addition of an acid reagent. The carbon dioxide gas is carried by the oxygen
carrier gas and measured with the NDIR CO
The TC result obtained from the TC analysis type represents the sum of TIC, NPOC and Purgeable
Organic Carbon (POC):
TC = TIC + NPOC + POC
6. At the end of the reaction, the oxidized sample liquid is discharged from the reactor with increased
oxygen flow.
analyzer. The result is displayed as Total Organic Carbon (TOC). This
2
analyzer. The result is displayed as Total Carbon (TC).
2
analyzer. The result is displayed
2
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