1. COD

Chinese name: Chemical Oxygen Demand

English name: Chemical Oxygen Demand

Definition: The amount of oxidant consumed to oxidize reducing substances in 1 liter of water sample under certain conditions, expressed in mg/L of oxygen. It reflects the degree of pollution caused by reducing substances in water. This indicator is also one of the comprehensive indicators of the relative content of organic matter.

Ingredients: sulfuric acid, silver sulfate, mercury sulfate, potassium dichromate

Range: Divided into two types based on different COD concentration values:

⑴ LR - range of 0-150mg/L;
⑵ HR - Range from 0 to 1500mg/L
⑶ HR+- The range is 0-15000mg/L.

Shelf life: 3 years

Applicable situation: This reagent is used to measure the COD values of surface water and wastewater.

The specific operation method is as follows:

(1) Packaged reagents: Take 2.0mL of water sample into a test tube containing reagents, tighten the tube cap, shake well, put it into a COD heating furnace for digestion for 2 hours, take it out, cool it to room temperature, and then put it into the DR/2500 spectrophotometer produced by Hach company. Measure directly using program 430 or 435.

(2) Bottled reagents: Take 3.0mL of reagent and fill it into an empty tube. Add about 0.03g of HgSO4 (HgSO4 is included with the reagent) to the test tube, and then follow the steps for packaging reagents.

2. Reagents for infrared oil analyzer

Refined carbon tetrachloride and non-toxic reagents are excellent extractants with high extraction rates, which can successfully separate oil and water.

Refined carbon tetrachloride (500mL): Ensure compliance with the indicators required by national standard methods.

Non toxic reagent (500mL): can be used for measuring water with high oil content in industries such as petrochemicals.

3. Online residual chlorine and total chlorine measurement reagents

definition:

(1) Residual chlorine (also known as free chlorine): Chlorine that exists in the form of hypochlorous acid, hypochlorite ions, and dissolved elemental chlorine.
(2) Compound chlorine: a portion of total chlorine present in the form of chloramines and organic chloramines.
(3) Total chlorine: Chlorine that exists in the form of "free chlorine", "compound chlorine", or both.

Principle:

(1) Determination of free chlorine: Under certain conditions, free chlorine directly reacts with N, N-diethyl-1,4-phenylenediamine (DPD) to form a red complex, and the concentration is proportional to the absorbance.
(2) Determination of total chlorine: Under certain conditions, in the presence of excess potassium iodide, measure its absorbance according to the above principle.

Reagent:

(1) Residual chlorine: One set of three bottles of this reagent
*Residual chlorine indicator solvent (500mL)
*Residual chlorine buffer (500mL)
* DPD（25g）

(2) Total Chlorine: One set of this reagent consists of three bottles
*Total chlorine indicator solvent (500mL)
*Total Chlorine Buffer (500mL)
* DPD（25g）

Shelf life: 1 year

Note: To prevent the color developer from becoming ineffective, the powder is added to the indicator during use.

4. Online silicon measurement reagent in water

This reagent set consists of five bottles:

⑴ Silicon Standard Solution
⑵ Molybdate 3 Reagent for Silica
⑶ Surfactant Solution (Citric Acid)
⑷ Amino Acid F Solution
⑸ Powder

Note: To prevent the color developer from becoming ineffective, the powder is added to amino acids during use.

Shelf life: 1 year

Operation method: Pour each corresponding reagent into the original silicon measurement reagent bottle.

COD reagent measurement result report

The use of DR/2500 spectrophotometer to measure COD is easy to operate, and the measurement results of the reagents prepared by our company are as follows:

Table 1 COD Standard Measurement Results

*Note: The data in the table represent the concentration of COD, measured in mg/L.

Using our company's reagents, impurities did not affect the COD measurement results, as shown in Table 2

Table 2 Data obtained from various water samples

*Note: The data in the table represent the concentration of COD, measured in mg/L. Water sample 1 is river water, while water samples 2 and 3 are domestic sewage.

1. COD reagent

Measurement range:

0－150 mg/L
0－1500 mg/L
0—15000mg/L

250ml/bottle, can make 80 samples,
500 milliliters per bottle can produce 160 samples,,

2. Reagent for infrared spectroscopic oil analyzer:

(1) Capacity: 500 milliliters per bottle,

3. Residual chlorine and total chlorine reagents

Capacity:

500 milliliters per bottle, a total of 2 bottles.

4. Online silicon testing reagent

Capacity:

2500 milliliters per bottle, a total of 4 bottles.

For price details, please call 021-58343760