GB 13650-2009Fenitrothion emulsifiable concentrates (English PDF)

3.1 Composition and appearance

This product should be compliant fenitrothion original drug is made, it should be pale yellow to dark brown stable homogeneous liquid, free from visible suspended and precipitates.

3.2 Technical Specifications

Fenitrothion EC shall comply with the requirements of Table 1.

Table 1 Fenitrothion EC Control Project Index

project

index

45% 50%

Fenitrothion content /% >= 45.0 + 2.2-2.2 50.0 + 2.5-2.5 S- methyl fenitrothion mass fraction /% <= 1.0 Moisture /% <= 0.3 Acidity (H2SO4 meter) /% <= 0.3 Emulsion stability (diluted 200 times) Qualified Low temperature stability a qualified Thermal storage stability of a qualified when a normal production, low-temperature storage stability and thermal stability test, every three months, at least once.

Test Method 4

4.1 Sampling

According to GB/T 1605-2001 5.3.2 in "liquid formulation sampled" in. Determining sample package using a random number table method, the final sample the amount of not less than 200mL.

4.2 Identification Test

Gas Chromatography --- The identification test can be carried out simultaneously with the determination of fenitrothion (S- methyl fenitrothion) mass fraction. In the same Chromatographic operating conditions, the sample solution to a chromatographic retention time and standard solutions fenitrothion (S- methyl fenitrothion) peaks Retention time, the relative difference should be less than 1.5%.

4.3 Determination of fenitrothion, S- methyl fenitrothion mass fraction

4.3.1 Method summary

Sample was dissolved in acetone to diallyl phthalate esters as internal standard, using a HP-5 capillary column and a flame ionization detector, Sample of fenitrothion, S- methyl fenitrothion and measured by gas chromatography, internal standard. You can also use a packed column gas chromatography Determination of spectrum, chromatographic operating conditions, see Appendix A.

4.3.2 Reagents and solutions

Acetone. AR;

Fenitrothion standard. a known mass fraction >=98.0%;

Internal standard. dimethyl phthalate, propylene carbonate, should not interfere with the analysis of impurities;

Internal standard solution. Weigh diallyl phthalate esters 2.5g, placed in 500mL volumetric flask, dissolved in acetone and diluted to the mark, Shake well.

4.3.3 Instruments

Gas chromatograph. with a hydrogen flame ionization detector, split/splitless inlet;

Chromatographic data processor or chromatography workstation;

Column. 30m × 0.32mm (i.d.) HP-5 capillary column, film thickness 0.25 m;

Micro injector. 10µL.

4.3.4 GC operating conditions

Temperature (°C). Room 210 column, the gasification chamber 230, detection chamber 270;

Gas flow rate (mL/min). carrier gas (N2) 1.5, makeup gas (N2 of) 30, hydrogen gas 30, air 300;

Split ratio. 50.1;

Injection volume. 1.0µL;

Retention time. fenitrothion 4.9min, S- methyl fenitrothion 6.4min, diallyl phthalate esters 3.2min.

The above operating conditions, the Department of typical operating parameters, according to the characteristics of different instruments and columns for a given operating parameters to make appropriate adjustments to to obtain the best results. Typical fenitrothion EC gas chromatography is shown in Figure 1.

1 --- internal standard (diallyl phthalate esters);

2 --- fenitrothion;

3 --- S- methyl fenitrothion.

Figure 1 Fenitrothion EC gas chromatogram

4.3.5 Measuring step

4.3.5.1 Preparation of standard solution

Weigh fenitrothion standard 0.1g (accurate to 0.0002g), placed in 15mL stoppered glass bottle with a pipette accurately added 10mL Internal standard solution, shake well.

4.3.5.2 Preparation of sample solution

Weigh the sample containing fenitrothion 0.1g of (accurate to 0.0002g), placed in 15mL stoppered glass vial with 4.3.5.1 with the same A pipette accurately added internal standard solution 10mL, shake.

4.3.5.3 Determination

Under these operating conditions, after the instrument is stable, continuous injection of several doses of the standard solution until the two adjacent needles fenitrothion and the internal standard peak area After the change of the relative volume ratio is less than 1.2%, according to the solution, the sample solution, the sample solution and standard sequence of the standard solution was measured.

4.3.6 Calculation

The two needles in the sample solution and measured before and after the two-pin standard sample solution fenitrothion and the internal standard peak area ratios are averaged.

1 sample mass fraction (%) of fenitrothion according to equation (1).

Where.

--- Fenitrothion standard mass fraction, expressed as a percentage.

The two needles in the sample solution is measured with S- methyl fenitrothion peak areas are averaged. Sample S- methyl fenitrothion 2 mass fraction (%) parathion according to formula (2).

2 = A2A1 ×

Where.

A1 --- sample solution, fenitrothion mean peak area;

A2 --- sample solution, the average S- methyl fenitrothion peak area;

1 --- sample fenitrothion mass fraction, expressed as a percentage.

4.3.7 Allowable difference

The difference between two parallel determination results, fenitrothion should be less than 0.5%, the arithmetic mean value as a measurement result.

4.4 Determination of Moisture

According to GB/T 1600 the "Karl Fischer method".

4.5 Determination of acidity

4.5.1 Reagents and solutions

95% ethanol;

Sodium hydroxide standard titration solution. Ba (NaOH) = 0.02mol/L;

Methyl red - bromocresol green mixed indicator solution. take 2mL methyl red ethanol solution (1g/L) and 10mL bromocresol green ethanol solution (1g/L) were mixed shake.

4.5.2 Measuring step

Weigh the sample 4g (accurate to 0.002g), placed in a 250mL conical flask, 40mL95% ethanol, shaking the sample solution Solution was added 2mL mixed indicator solution, titration with sodium hydroxide standard titration solution to dark green as the end point.

Meanwhile blank determination.

4.5.3 Calculation

The acidity of the sample 3 (%), according to equation (3) Calculated.

3 = Ba

· (Vp Vp 1- 0) · M

Where.

Ba --- the actual concentration of sodium hydroxide standard titration solution, expressed in moles per liter (mol/L);

Vp 1 --- titration of the sample solution, the volume of consumption of sodium hydroxide standard titration solution, in milliliters (mL);

V0 --- titrate blank solution, the volume of consumption of sodium hydroxide standard titration solution, in milliliters (mL);

--- The M values of the molar mass of sulfuric acid, in units of grams per mole (g/mol), [M (1/2H2SO4) = 49g/mol].

4.6 Emulsion stability test

Standard hard water sample was diluted 200-fold, according to GB/T 1603 test, the non-oil slick, the absence of heavy oil and precipitated as qualified.

4.7 Low temperature stability test

According to GB/T 19137 in "homogeneous emulsion and liquid preparations" to. The bottom of the centrifuge tube educt volume of less than 0.3mL qualified.

4.8 Thermal storage stability test

According to GB/T 19136 in "liquid formulation" to. After the heat storage fenitrothion content should not be lower than before the heat storage mass fraction of 95% S- methyl fenitrothion content should not exceed 1.5%, other indicators should continue to meet the standards.

4.9 Product testing and acceptance

Shall comply with GB/T 1604's. Treatment of extreme values using the rounding value comparison method.