GB 22601-20082, 4-D butyl emulsifiable concentrates (English PDF)

3.1 Composition and appearance

This product should meet the standards of the original drug 2,4-butyl ester prepared as a homogeneous oily liquid without visible suspended matter and sediment.

3.2 Technical Specifications

2,4-D butyl EC shall comply with the requirements of Table 1.

Table 1 2,4-D butyl EC indicators Control Project

project

index

57% 72% 900g/L 999g/L Butyl 2,4 mass fraction of a /% or 2,4-D butyl ester concentration (20 °C) / (g/L) 57.0 + 2.5-2.5 72.0 + 2.5-2.5 76.0 + 2.5-2.5 + 25-25 900 82.5 + 2.5-2.5 + 25-25 999 Free phenol content (2,4-DCP meter) /% <= 0.6 0.8 0.8 0.9 Moisture content /% <= 0.8 pH range of 3.0 to 7.0 Emulsion stability (diluted 200 times) Qualified Low temperature stability Qualified b Thermal storage stability b qualified when a dispute occurs when the mass to the mass fraction of arbitration.

b low temperature stability test, the thermal storage stability tests at normal production, at least every three months, once detected.

Test Method 4

4.1 Sampling

According to GB/T 1605-2001 in "liquid formulations sampling" approach. Determined by sampling a random number table method packages, the final sample size not less than 200mL.

4.2 Identification Test

Gas Chromatography --- The identification test can be carried out simultaneously with the determination of 2,4-D butyl ester content. Under the same chromatographic operating conditions, the test the retention time of the sample solution and the standard solution to a peak of 2,4-D butyl ester peak retention time, the relative difference should be 1.5% Fewer.

4.3 Determination of the mass fraction of 2,4-D butyl ester

4.3.1 Method summary

Sample was dissolved in chloroform, di-isobutyl phthalate as internal standard, the use of polyethylene terephthalate and tetrachlorophthalic Apiezon L is a stainless steel column filler and a flame ionization detector, the sample of 2,4-butyl gas chromatography and measurement set. Determination can also be used by capillary gas chromatography, chromatographic operating conditions given in Appendix A.

4.3.2 Reagents and solutions

Chloroform;

2,4-D butyl standard. a known mass fraction >=98.0%;

Internal standard. di-iso-butyl phthalate, should not interfere with the analysis of impurities;

Internal standard solution. Weigh isobutyl phthalate 3.5g, set 250mL flask, add appropriate amount of chloroform was dissolved and diluted to Mark and shake.

4.3.3 Instruments

Gas chromatograph. with a hydrogen flame ionization detector;

Chromatography or chromatography workstation processor;

Column. 2m × 3mm (i.d.) Stainless steel (glass) columns, built-in 1.7% tetrachlorophthalic polyethylene terephthalate and 0.3% Appius Song L/ChromosorbW-AWDMCS180 ~ 250µm filler;

Micro injector. 10µL.

4.3.4 GC operating conditions

Temperature (°C). Column temperature. 170, 260 gasification chamber, the detector chamber 260;

Gas flow rate (mL/min). carrier gas (N2) 20, hydrogen gas 30, air 300;

Injection volume. 0.6µL;

Retention time (min). 2,4- 11.0 butylate, internal standard 6.7.

It said operating parameters are typical, according to the characteristics of different instruments, given operating parameters adjusted as appropriate, in order to obtain the best results.

A typical gas chromatogram of 2,4-D butyl EC and the internal standard is shown in Figure 1.

1 --- internal standard;

2 --- 2,4-D ester.

Figure 1 Gas chromatograms butyl 2,4-EC and the internal standard

4.3.5 Measuring step

4.3.5.1 Preparation of standard solution

Weigh 2,4-butyl standard 0.1g (accurate to 0.0002g), placed in a glass bottle stuffed with a pipette 5mL internal standard solution Liquid, shake.

4.3.5.2 Preparation of sample solution

Weigh containing 2,4-D butyl ester 0.1g (accurate to 0.0002g) sample, placed in a glass vial stopper, and 4.3.5.1 with the same Pipette internal standard solution 5mL, 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 needle relative peak area of 2,4-butyl After the change is less than 1.2%, according to the solution, the sample solution, the sample solution and standard sequence of the standard solution was measured.

4.3.5.4 Calculation

The ratio measured before and after the two-needle sample solution and two doses of the standard sample solution of 2,4-butyl and the internal standard peak area, respectively average. Sample mass fraction of 2,4-D butyl ester 1 (%) according to equation (1) calculation of the concentration of 2,4-D butyl rho1 (g/L) according to equation (2) Calculated.

rho1 =

Where.

Density rho --- 20 °C when the sample in grams per milliliter (g/mL) (according to GB/T 4472 measured);

--- Standard samples of 2,4-butyl ester content, expressed as a percentage.

4.3.6 Allowable difference

2,4-D butyl ester content (mass concentration) of two parallel determination results relative difference should be less than 1.5%, and the arithmetic mean for to determine the results.

4.4 Determination of free phenols

4.4.1 Method summary

The sample was dissolved in ethanol, ammonia, 4-amino-antipyrine and potassium ferricyanide solution color, absorbance was measured at 520nm place.

Isolated from the calibration curve of standard sample absorbance at the same volume, calculated free phenol content.

4.4.2 Reagents and solutions

2,4-dichlorophenol standard. a known mass fraction >=98.0%;

Ethanol;

Isopropanol;

Ethanol, isopropyl alcohol solution. psi (ethanol. isopropanol. water) = 2.1.3;

Ammonia solution. Ba (NH3 · H2O) = 0.1mol/L;

2,4-DCP standard solution. Weigh 2,4-dichlorophenol standard 0.01g (accurate to 0.0002g), placed in 100mL volumetric flask, add A small amount of ethanol to dissolve, diluted with ethanol to the mark;

4-amino-antipyrine solution. rho = 2g/L;

Ferricyanide solution. rho = 4g/L.

4.4.3 Instruments and equipment

Spectrophotometer;

Microburette. 2mL;

Stoppered cylinder. 30mL;

Quartz cuvette. 1cm.

4.4.4 Measuring step

4.4.4.1 Correction

Followed by microburette draw 0.2mL, 0.5mL, 0.8mL, 1.0mL, 1.2mL, 1.5mL, 2.0mL2,4- dichlorophenol standard Sample solution, adding seven stoppered graduated cylinder, fill with ethanol was added to 10mL, then followed by adding 5mL of isopropanol, 5mL ammonia solution, 5mL4- ammonia Karthikeyan antipyrine 5mL aqueous potassium ferricyanide solution. Each addition are required to shake, and the last intense shaking 1min, standing 5min. Quartz cuvette, ethanol isopropyl alcohol solution as the reference absorbance at 520nm measured.

Draw 10mL ethanol, according to the procedure described above was added to each solution, determine the reagent blank absorbance.

Blank value is subtracted from the phenol solution absorbance measured absorbance, the corresponding volume of phenol solution was plotting a calibration curve.

4.4.4.2 Determination

Weigh containing 2,4-D butyl ester 0.2g (accurate to 0.0002g) sample, placed in 100mL flask, add a small amount of ethanol solution Solution, dilute to the mark with ethanol. With a pipette to the solution of 10mL stoppered measuring cylinder and then followed by adding 5mL of isopropanol, 5mL Ammonia solution, 5mL4- amino antipyrine 5mL aqueous potassium ferricyanide solution. Each addition are required to shake, and the last intense shaking 1min, standing 5min. Quartz cuvette, ethanol isopropyl alcohol solution as the reference absorbance at 520nm measured. Minus empty After the absorbance values of white, from the calibration curve of the absorbance corresponding to 2,4-DCP standard solution volume (mL) to detect.

2 free phenol content (%) according to equation (3) Calculated.

Where.

Vp --- measured absorbance of the sample corresponding to the volume of phenol solution in milliliters (mL);

--- Sample mass fraction of 2,4-dichlorophenol in%.

4.5 Determination of Moisture

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

According to GB/T 1601 carried out.

4.7 Emulsion stability test

Standard hard water sample was diluted 200-fold, according to GB/T 1603 test, the non-oil slick, no precipitation under qualified.

4.8 Low temperature stability test

According to GB/T 19137 in "homogeneous emulsion and liquid preparations", in the bottom of the centrifuge tube educt volume does not exceed 0.3mL qualified.

4.9 Thermal storage stability test

According to GB/T 19136 in "liquid formulation" to. After the thermal storage, 2,4-D butyl ester content should not be lower than the measured mass fraction before hot storage 95% emulsion stability should continue to meet the standards.

4.10 Product inspection and acceptance

Shall comply with GB/T 1604's. Limit the use of numerical treatment rounding value comparison method.