GB/T 32812-2016Metal working fluid - Limit requirements and determination methods of hazardous substance (English PDF)

3.1 Metal working fluid

The medium used for lubrication, cooling, rust prevention and cleaning of metals and their alloys in the cutting and forming process.

Note: It is divided into water-based metal working fluid, oil-based metal working fluid. The form includes liquid, semi-fluid or solid.

3.2 […]

5.1 Sampling

Sampling of metal working fluid shall be carried out in accordance with the provisions of GB/T 4756.

5.2 Nitrite NO 2

-

The content of nitrite in the metal working fluid is determined using nitrite NO 2

- test paper. The arbitration test is carried out in accordance with SN/T 2704.3.

5.3 Nonylphenol polyoxyethylene ether

See Appendix A for the determination of nonylphenol polyoxyethylene ether content in metal working fluids.

5.4 Short-chain chlorinated paraffin

See Appendix B for the determination of short-chain chlorinated paraffin content in metal working fluids.

5.5 Polycyclic aromatic hydrocarbons

See Appendix C for the determination of the content of polycyclic aromatic hydrocarbons in metal working fluids.

5.6 Diethanolamine

See Appendix D for the determination of diethanolamine content in metal working fluids.

5.7 Lead

The determination of lead content in metal working fluid is carried out according to the following steps:

a) TAKE 1 g of sample in a porcelain crucible; HEAT and carbonize it on an electric hot plate; ADD 2 mL of concentrated nitric acid and 5 drops of concentrated sulfuric acid; carefully heat until the white fume is exhausted;

MOVE it into a 550 °C high-temperature furnace for ashing (6 h~8 h);

b) TAKE it out after cooling; ADD 1 mL of nitric acid (1+1) solution; HEAT to dissolve the ash. If the ash of the sample is not completely dissolved, add

1 mL of mixed acid (nitric acid : perchloric acid=9 : 1) solution; HEAT to […]

A.1 Overview

This appendix specifies the liquid chromatography detection method for nonylphenol polyoxyethylene ether (n=2~10) in water-based metal working fluids.

A.2 Method

After taking 1 g of sample and adding 10 mL of ethanol for extraction, the ethanol extract is determined by liquid chromatography and quantified by external standard method.

A.3 Reagents and standard solutions

Reagent and standard solution requirements:

- Methanol (HPLC grade);

- Acetonitrile (HPLC grade);

- Ethanol (analytical purity);

- Pure water; the resistivity is greater than 18.2 Mohm · cm;

- Nonylphenol polyoxyethylene ether standard; average degree of polymerization n=9; purity is >=99%;

- Nonylphenol polyoxyethylene ether standard solutions: Accurately weigh an appropriate amount of nonylphenol polyoxyethylene ether; USE methanol to dilute; prepare a series of standard working solutions of the required concentration 10 mg/L, 50 mg/L, 100 mg/L, 200 mg/ L and 500 mg/L.

A.4 Apparatus

Test apparatus and related requirements:

- High performance liquid chromatograph, equipped with fluorescence […]

B.1 Overview

This appendix specifies the detection method for the content of C10~C13 short- chain chlorinated paraffins in the metal working fluid with a concentration (mass fraction) ranging from 0.1%~2.5%.

B.2 Method

TAKE 0.2 g of sample and add 10 mL of n-heptane to dilute or extract; then take the diluent or extract into the gas chromatograph with ECD detector for analysis.

B.3 Reagents and materials

Reagent and material requirements:

- N-heptane; the purity is not less than 99%;

- C10~C13 chlorinated paraffin standard; the purity is not less than 99%;

- C10~C13 chlorinated paraffin n-heptane standard solution: WEIGH an appropriate amount of C10~C13 chlorinated paraffin standard; USE n- heptane as the dilution solvent; prepare C10~C13 chlorinated paraffin n- heptane standard solutions with concentrations of 20 mg/L, 50 mg/L, 100 mg/L, 200 mg/L and 500 mg/L, respectively.

B.4 Apparatus

Test apparatus and related requirements:

- Gas chromatograph, equipped with electron capture detector (ECD) and automatic injection device;

- Pipette, 1 mL;

- Measuring cylinder, 10 mL;

- Glass sample bottles with screw caps, 1.5 mL and 25 mL;

- Microinjector, 10 µL or higher accuracy;

C.1 Overview

This appendix specifies the liquid chromatography detection method for the content of polycyclic aromatic hydrocarbons (PAHs) and benzopyrene (BaP) in metal working fluids.

C.2 Method

After the sample is diluted or extracted by n-heptane, it is determined by a high performance liquid chromatograph equipped with a polar chromatographic column and a differential refractive index detector; quantified by the external standard method. The total content of polycyclic aromatic hydrocarbons is the mass sum of bicyclic aromatic hydrocarbons and above-tricyclic aromatic hydrocarbons.

C.3 Reagents and standard solutions

Reagent and standard solution requirements:

- Cyclohexane (analytical pure), without benzene;

- N-heptane (HPLC grade), as the mobile phase;

- O-xylene (analytical purity); the purity is greater than 98%;

- Hexamethylbenzene; the purity is greater than 98%;

- Naphthalene; the purity is greater than 98%;

- Dibenzothiophene; the purity is greater than 95%;

- 9-methylanthracene; the purity is greater than 95%;

- Fluorene; the purity is greater than 98%;

- Phenanthrene; the purity is greater than 98%;

- Benzopyrene; the purity is greater than 98%;

C.5.2 Liquid chromatographic analysis conditions

Typical liquid chromatographic analysis conditions are as follows. Other chromatographic columns and analysis conditions, which can achieve the same separation effect, can also be used:

- Serial chromatographic columns: one NH 2 column (150 mm×4.6 mm×5 µm) and one SB-CN column (150 mm×4.6 mm×5 µm);

- Chromatographic column temperature: 35 °C;

- Mobile phase: n-heptane;

- Refractive index range of the differential refractive index detector is 1.3~1.6;

- Flow rate: 1.0 mL/min;

- Injection volume: 10 µL.

C.5.3 Sample determination

C.5.3.1 Determination of content of polycyclic aromatic hydrocarbons

The mixed calibration solutions A to D of polycyclic aromatic hydrocarbons are determined sequentially. According to the chromatographic peak area and the corresponding concentration, establish a standard working curve. According to the retention time of o-xylene, fluorene and phenanthrene, determine the integration domain of chromatographic peak of monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, tricyclic and above-tricyclic aromatic hydrocarbons. And use the polycyclic aromatic hydrocarbon reference solution SCS1 to verify and confirm. TAKE 10 µL of sample into liquid chromatograph for determination. From the retention time and peak area of bicyclic aromatic hydrocarbons, tricyclic and above-tricyclic aromatic hydrocarbons, the corresponding content of polycyclic aromatic hydrocarbons can be obtained from the standard working curve.

C.5.3.2 Determination of benzopyrene content

First, the benzopyrene series standard working solutions are determined sequentially from dilute to concentrated. According to the chromatographic peak area and the corresponding concentration, establish a standard working curve. TAKE 10 µL of sample into liquid chromatograph for determination. From […]

D.1 Overview

This appendix specifies the detection method for diethanolamine content in water-based metal working fluids with a concentration (mass fraction) ranging from 0.1%~2%. Samples with diethanolamine content (mass fraction) higher than 2% can be tested after being diluted with ethanol.

D.2 Method

After the metal working fluid is extracted using ethanol, it is analyzed by gas chromatograph.

D.3 Reagents and materials

Reagent and material requirements:

- Diethanolamine; the purity is not less than 99%;

- Ethanol, analytically pure;

- Preparation of the standard stock solution of diethanolamine: Accurately weigh 0.5 g of diethanolamine into a 100 mL volumetric flask; USE ethanol to dilute to the mark and mix well. The concentration of the standard stock solution is 5000 mg/L;

- Diethanolamine standard working solutions: PIPETTE an appropriate amount of standard stock solution and use ethanol to dilute, to prepare concentrations of 100 mg/L, 200 mg/L, 500 mg/L, 1000 mg/L and 2000 mg/L, respectively.

D.4 Apparatus

Test apparatus and related requirements:

- Gas chromatograph, equipped with FID detector and automatic injection device;

- Ultrasonic cleaner;

- Pipette, 1 mL;