GB/T 19604-2017 in English

Interpretation of GB/T 19604-2017 Chlorpyrifos Technical Standard

1. Analysis of Standard Background and Technology Evolution

GB/T 19604-2017 Chlorpyrifos Technical Standard is revised on the basis of GB/T 19604-2004. The main technical changes include:

• The mass fraction of chlorpyrifos is increased from no less than $95.0\%$ to no less than $97.0\%
• The control index of acetone insoluble matter is reduced from no more than $0.5\%$ to no more than $0.2\%
• New phosphorus control control index

2. Standard Framework Comparison Table

3. Technical indicators and test methods

3.1 Determination of mass fraction of chlorpyrifos

Liquid chromatography is an arbitration method, suitable for accurately measuring the mass fraction of chlorpyrifos. Use C18 chromatographic column and UV detector, separate at $290~\mathrm{nm}$ wavelength, and quantify by external standard method.

3.2 Determination of phosphorus control mass fraction

Gas chromatography combined with internal standard method was used to quantify phosphorus control. Using HP-5 capillary column and hydrogen flame ionization detector, the retention time was $17.3~\mathrm{min}$.

3.3 Determination of moisture

The Karl Fischer method was used, which is suitable for rapid and accurate determination of the moisture content in chlorpyrifos technical. The standard stipulates that the moisture/% shall not exceed $0.3$.

Implementation recommendations

• It is recommended that enterprises strictly control the mass fraction of chlorpyrifos during the production process to ensure that it meets the requirements of $\geq 97.0\%$.
• Regularly test acetone insoluble matter and phosphorus control indicators to ensure stable product quality.
• Liquid chromatography should be used as a priority to determine the mass fraction of chlorpyrifos in arbitration inspections.

4. Implementation and significance of the standard

The revision and implementation of GB/T 19604-2017 further improved the quality requirements of chlorpyrifos technical, which is of great significance to ensuring the quality of pesticide products and promoting sustainable agricultural development.