Unlock Exclusive Discounts & Flash Sales! Click Here to Join the Deals on Every Wednesday!

Determination of total organic carbon in electroplating waste liquid by wet chemical oxidation technology (CAT#: STEM-PPA-0116-LJX)

Introduction

The waste electroplating liquid contains chromium, zinc, copper, nickel, silver, lead and other heavy metals, as well as chloride, organic matter, acid and so on. The salt content and acid content in the waste liquid can reach tens of thousands of ppm, which makes the determination of the organic content in the waste liquid very complicated.<br />The detection limit of TOC by wet oxidation method is lower than that by high temperature combustion method, and the reaction is relatively mild, and the influence of chloride ions is relatively less. Therefore, wet oxidation method can be used to determine the total organic carbon in electroplating waste liquid.




Principle

Both inorganic carbonates and organic pollutants in water contain carbon, and their total amount is called total carbon (TC). The carbon in all inorganic carbonates is called total inorganic carbon (TIC), and the carbon in all organic matter is called total organic carbon (TOC).
The wet oxidation method can detect TIC, TOC and TC in the same sample simultaneously. The water sample enters the digestion reactor through the automatic sampling loop tube, reacts with 5%(v/v) phosphoric acid at first, and the CO2 produced by decomposition is blown out by high purity nitrogen, and then enters the gas infrared detector (NDIR) to detect TIC after dehumidification through the drying tube. Then sodium persulfate oxidant was added to the digester to react quickly with various organic matter in the water sample at 100℃, and the CO2 produced by decomposition was also entered into the gas infrared detector to detect TOC. The amount of CO2 detected is proportional to the amount of TIC and TOC in the water sample, respectively.

Applications

For the determination of total organic carbon in liquids

Procedure

1. The water sample enters the digestion reactor through the automatic sampling loop
2. The inorganic carbonate in the water sample reacts with 5%(v/v) phosphoric acid, and the CO2 produced by decomposition is blown out by high-purity nitrogen, which is dehumidified through the drying tube and then enters the gas infrared detector (NDIR) for TIC detection
3. Sodium persulfate oxidizer is added to the digester to react rapidly with various organic matter in the water sample at 100℃, and the CO2 generated by decomposition is also entered into the gas infrared detector to detect TOC
4. The sum of TIC and TOC is the TC content

Materials

• Sample Type:
Electroplating waste liquid

Notes

The container used for sampling must be kept clean and free of organic contamination.