Soil and sediments. Determination of sulfide. Methylene blue spectrophotometric method (2)

5.

(1) Pre-treatment of the sample

Collect soil samples according to the relevant regulations of HJ/T166, and collect sediment samples according to the relevant regulations of CB17378.

The collected sample should be filled with the container and stored in a brown ground glass bottle with a stopper, and measured within 24 hours

Determination of the dry matter content and moisture content of the sample: While the sample is being measured, the dry matter content of the soil sample is measured in accordance with the relevant regulations of HJ613, and the moisture content of the sediment sample is measured in accordance with the relevant regulations of GB17378.

(2) Preparation of samples

1.

Weigh 20g of sample (if the concentration of sulfide is high, you can take less sample as appropriate), accurate to 0.

2.

Weigh 20g of sample (if the concentration of sulfide is high, you can take less sample as appropriate), accurate to 0.

Six, analysis and testing

(1) Drawing of standard curve

Take 9 100mL colorimetric tubes with stopper, add 10.

(2) Measurement of sample

1.

Remove the colorimetric tube, add water to about 60mL, and measure the absorbance of the sample in the same way as the standard solution

2.

Remove the colorimetric tube, and measure the absorbance of the sample in the same way as the standard solution

(3) Determination of blank samples

Perform the measurement of the blank sample in the same way as the sample

Related Links: Determination of Sulfide in Soils and Sediments Methylene Blue Spectrophotometry (1)