These seven steps can be followed during the work of the TOC detector
This instrument adopts the principle of oxidation under the action of ultraviolet rays and catalyst catalysis to oxidize the organic matter in the sample to carbon dioxide. The total organic carbon content is determined by the difference in the total inorganic carbon content of the sample, that is: total organic carbon (TOC) = total carbon (TC) - total inorganic carbon (TIC).
Determination method of TOC detector:
1. Direct measurement method:
Pre-acidify the water sample, pass nitrogen aeration to drive off the carbon dioxide generated by the decomposition of various carbonates, and then inject it into the instrument for measurement. During the aeration process, the loss of volatile organic compounds will cause errors, so the measurement result is the carbon value of organic compounds that cannot be blown out.
2. Subtraction method:
When the same amount of water sample is injected into a high temperature furnace (900°C) and a low temperature furnace (150°C), the organic carbon [1] and inorganic carbon in the water sample are converted into carbon dioxide, and the organic matter in the quartz tube of the low temperature furnace cannot be decomposed oxidation. The difference between total carbon (TC) and inorganic carbon (TIC) measured in high and low temperature furnaces is total organic carbon (TOC).
The operation of the TOC detector can be divided into 7 steps:
1) First turn on the heating program of the combustion furnace, and then measure when the temperature rises to about 680°C;
2) Select the measurement method on the main menu;
3) Select the measuring range according to the concentration range of the standard solution;
4) Determine whether to execute a blank program. In general, samples with low concentration must perform blank measurement;
5) Enter the number of standard samples;
6) Input the number of samples to be tested n+1, n represents the actual number of samples, and add another pure water sample to clean the channel;
7) The instrument automatically injects samples, automatically detects and displays the TOC concentration value.
