HJ 867-2017Ambient air. Determination of phthalate esters. Gas chromatography/mass spectrometry (English PDF)

5.5 Anhydrous sodium sulfate (Na2SO4)

Bake in a muffle furnace at 450 °C for 4 h before use, cool, and store in sealed glass jar.

25.6 decafluorotriphenylphosphine (DFTPP). rho = 50 µg/ml, can be purchased directly from the certified public standard solution, or with a high concentration of standard solution with system.

5.7 ether - n-hexane mixed solution. 1 9, Pro use now.

5.8 ether - n-hexane mixed solution. 2 8, Pro use now.

5.9 acetone - n-hexane mixed solution. 1 9, Pro use now.

5.10 methylene chloride - n-hexane mixed solution. 2 8, Pro use now.

5.11 diphenyl phthalate (C20H14O4). purity of 98% or more.

Alternatives may also be used.

5.12 Substitute stock solution. rho =.2000 µg/ml.

Weigh diphenyl phthalate (5.11) about 0.1 g, accurate to 0.1 mg, in 50 ml volumetric flask, dissolved in a small amount of acetone, with n-hexane (5.2) constant volume, mix well. 4 °C the following sealed. Can also be purchased directly from the market certified standard solution.

5.13 Alternative solution. rho = 80.0 µg/ml.

Pipette 1.00 ml of stock solution (5.12) into a 25 ml volumetric flask, dilute with n-hexane (5.2) and mix well. 4 °C below the dense Save sealed.

5.14 Internal standard stock solution. rho = 4000 µg/ml.

Direct purchase of a certified public standard solution, with 苊-D10, Philippines-D10, -D12, reference standard solution certificate.

5.15 Internal standard solution. rho = 1000 µg/ml.

The internal standard stock solution (5.14) was diluted to 1000 µg/ml with dichloromethane (5.1). 4 °C below the sealed dark save.

5.16 Diisobutyl phthalate Reference material. purity 98% or more.

5.17 Diisobutyl phthalate stock solution. rho =.2000 µg/ml.

Weigh 0.1 g of diisobutyl phthalate standard (5.16), accurate to 0.1 mg in a 50 ml volumetric flask with n-hexane (5.2) Dissolve and set the volume, mix well. 4 °C the following sealed. Can also be purchased directly from the market certified standard solution.

5.18 6 phthalates standard stock solution. rho =.2000 µg/ml.

Direct purchase of a certified commercial standard solution, including dimethyl phthalate, diethyl phthalate, dibutyl phthalate, o Butyl phthalate, di-2-ethylhexyl phthalate and di-n-octyl phthalate in n-hexane.

4 °C below the preservation, or reference standard solution certificate preservation.

5.19 8 phthalates standard solution. rho = 80.0 µg/ml.

Remove phthalate standard stock solution (5.17), (5.18) and replacement stock solution (5.12) each 1.00 ml, in 25 ml capacity Volume flask with n-hexane (5.2) constant volume, mix well. 4 °C the following sealed.

5.20 Magnesium silicate. 150 µm to 250 µm (100 mesh to 60 mesh). Before use, weigh 100 g ± 10 g into an evaporating dish at 140 ° C Heated 16 h, while hot transferred to 500 ml grinding mouth reagent bottle, capped cooled to room temperature, add 3.0 ml +/- 0.1 ml experimental water, sealed, Shake well for 10 min and let stand for 2 h.

5.21 Magnesium silicate SPE. 1000 mg/6 ml. According to the content of impurities can also choose the appropriate capacity of commercial solid phase extraction column.

5.22 glass (or quartz) fiber filter. according to the sampling head to select the appropriate size of the filter. The retention of the membrane on 0.3 µm standard particles the rate of not less than 99%, air flow velocity of 0.45 m/s, leaflets filter resistance of not more than 3.5 kPa.

3 before use in a muffle furnace at 400 °C heating 5 h or more, cooled, wrapped with aluminum foil, stored in a filter box, to avoid direct connection with the plastic Touch, to ensure that the filter before sampling and sampling is not stained, and in the flat before the sample is not folded state.

5.23 XAD-2 resin (styrene-divinylbenzene polymer). 250 µm to 840 µm (60 mesh to 20 mesh).

Before extraction with dichloromethane (5.1) reflux 16 h, the replacement of dichloromethane (5.1) to continue reflux extraction 16 h, then ether -N-hexane mixed solution (5.7) refluxed 16 h, vacuum dried at room temperature 2 h ~ 3 h. Keep in a clean glass bottle.

5.24 Polyurethane Foam (PUF). polyether type, with a density of 22 mg/cm3 to 25 mg/cm3, cut for growth of 25 mm and 50 mm, straight Cylindrical diameter of 45 mm to 65 mm (length, diameter as determined by the specifications of the glass sampling cartridge).

Wash with experimental water before use, drained, rinsed three times with acetone (5.4) and placed in a Soxhlet extractor (6.4), followed by C Ketone (5.4), diethyl ether - n-hexane mixed solution (5.7) refluxed 16 h, during the replacement of 2 to 3 times the fresh ether - hexane mixed solution Liquid (5.7). Room temperature vacuum drying 2 h ~ 3 h (also available nitrogen (5.25) dry). Wrap with aluminum foil and seal in a suitable container save.

5.25 Nitrogen. Purity >=99.999%.

5.26 Helium. Purity >=99.999%.

5.27 glass wool. before use dichloromethane (5.1) reflux extraction 2 h ~ 4 h, dried and sealed.

7.1 Sample collection

Sample collection meets HJ 691 requirements.

Phthalates in the ambient air exist in the gas phase, particulate matter or both exist at the same time, you must also use glass (or quartz) fiber filter, XAD-2 resin and polyurethane foam collection.

Before sampling the membrane filter and glass sampling tube installed in the filter holder and the sampling sleeve, connecting the sampler, adjusting the sampling flow, the beginning sampling. Remove the filter after the sample is finished, the sample dust to the inside of the fold, remove the glass sampling tube, and fold the filter together with aluminum foil wrapped, Put in the original box sealed.

Collect the site before the sample collection blank, sealed glass sampling tube and filter membrane to the sampling site, the sampling head is not installed Sampling, and then remove the glass sampling cartridge and filter, sealed with the same sample and sealed, with the sample shipped back to the laboratory.

7.2 Sample preservation

After the sample was collected, it was refrigerated below 4 °C and extracted within 7 days. The sample extract is stored below 4 ° C and stored in 40 days 5 analysis.

7.3 Sample Preparation

7.3.1 Sample Extraction

Put the filter and glass sample tube into a Soxhlet extractor (6.4), add 250 µl of alternative liquid (5.13) to XAD-2 resin, Add 500 ml diethyl ether - n-hexane mixed solution (5.7), reflux extraction 16 h or more, hourly reflux not less than 3 times to 4 times. Extracted Completed, cooled to room temperature, remove the bottom bottle, rinsed the extraction cup interface, the cleaning fluid will be transferred into the bottom bottle. Add a little anhydrous sodium sulfate (5.5) to sodium sulfate particles can be free-flowing, dehydration drying 30min.

Note. As long as the quality control requirements of this standard can be met, other sample extraction methods may also be used.

7.3.2 Sample concentration

The sample extract was transferred to a concentration flask, concentrated at below 45 °C, the solvent was replaced by n-hexane, concentrated to about 1 ml until Purification.

7.3.3 Sample Purification

7.3.3.1 Magnesium silicate column

The bottom of the glass column (6.5) is filled with glass wool (5.27), 2 cm of anhydrous sodium sulfate (5.5) and n-hexane (5.2) the agent is wet-filled with 10 g of magnesium silicate (5.20), expelled the air bubble, and the upper portion is added with 1 cm-2 cm of anhydrous sodium sulfate (5.5). Use 40 ml of n-hexane the alkane (5.2) pre-rinsed the column and controlled the flow rate to about 2 ml/min to keep the liquid level slightly higher than the packed bed and transfer the concentrated liquid (7.3.2) to the column, the vial was washed twice with 1 ml of n-hexane and transferred to the column. Rinse the column with 40 ml of n-hexane and discard the flow Liquid. The column was eluted with.200 ml diethyl ether-n-hexane mixed solution (5.8) at an elution rate of 2 ml/min to 5 ml/min to receive the eluate.

The eluent was concentrated to 1.0 ml or less according to 7.3.2, fixed to 1.0 ml, and 10.0 µl of internal standard solution (5.15) was transferred to the sample Bottle to be analyzed.

7.3.3.2 Magnesium silicate solid phase extraction column

Take solid-phase extraction column (5.21), followed by 10 ml of acetone - n-hexane mixed solution (5.9), 10 ml of n-hexane (5.2) Phase extraction column, discard the effluent. Keep the liquid level just above the bed and transfer the extract concentrate (7.3.2) to the column and wash with 1 ml n-hexane (5.2) the vial was washed twice and transferred to the column, followed by 5 ml n-hexane (5.2), 10 ml dichloromethane-n-hexane mixed solution (5.10) Rinse solid-phase extraction column, the effluent discarded. Elute with 10 ml of acetone-n-hexane mixed solution (5.9) and receive the eluate.

The eluent was concentrated to 1.0 ml or less according to 7.3.2, fixed to 1.0 ml, and 10.0 µl of internal standard solution (5.15) was transferred to the sample Bottle to be analyzed.

Note. As long as the quality control requirements of this standard can be met, other sample purification methods, solid phase columns of different specifications and different batch numbers of magnesium silicate may be used for elution the amount of solvent may be different, the need to conduct the conditions before use experiments.

7.4 Preparation of blank samples

7.4.1 Site blank

Site blank (7.1) Prepare a site blank sample following the same procedure as for sample preparation (7.3).

7.4.2 Laboratory blank

6 same batch of glass sampling cartridges and filters in accordance with the same sample preparation steps (7.3) Preparation of laboratory samples blank.

8.1 Instrument reference conditions

8.1.1 GC reference conditions

Inlet temperature. 250 °C; Injection mode. split injection, split ratio 10.1; injection volume. 1.0 µl; column temperature. 45 °C for 2 min, Raise temperature to 320 ° C at 10 ° C/min for 5.5 min; Carrier gas. Helium (5.26), Flow rate. 1.0 ml/min.

8.1.2 Reference conditions for mass spectrometry

Transmission line temperature. 280 °C; Ion source temperature. 250 °C; Ion source electron energy. 70 eV; Mass range. 35 amu ~ 500 amu;

Scan mode. full scan; solvent delay time. 10 min; electron multiplier voltage. consistent with the tuning voltage; the remaining parameters with reference to the instrument Use manual to set.

8.2 Instrument Performance Check

Before calibration, inject 1.0 µl of DFTPP solution (5.6), and the key ion abundance of DFTPP obtained by GC-MS system should satisfy the table 1 requirements; otherwise some parameters of the mass spectrometer need to be adjusted or cleaned of the ion source.

Table 1 DFTPP key ion abundance criteria

Mass ion m/z abundance standard mass ion m/z abundance standard

88.3.3 Establishment of standard curve

Taking the ratio of the concentration of the target compound to the concentration of the internal standard compound as the abscissa, the ratio of the peak area ratio of the target compound and the internal standard compound the value is ordinate, using the least squares method to draw the standard curve. Non-linear fitting curves can also be used for calibration, but at least 6 concentration points should be used.

8.4 Determination of the sample the sample is measured according to the same instrument conditions as the standard curve, and the peak area and retention time of the quantitative ion are recorded.

8.5 Blank test

The blank sample (7.4) is measured according to the same instrument conditions as the sample.

9 results calculated and expressed

9.1 Qualitative analysis Data was acquired in full scan to determine the relative retention time (RRT) of the target compound in the sample, the qualifier ions, and the quantitative ion peak Area ratio (Q) Qualitative. The relative retention time of the target compound in the sample and the relative retention time of the compound at the midpoint of the standard curve the difference should be within ± 0.03. The difference between the Q value of the target compound in the sample and the Q value at the midpoint of the standard curve is controlled within ± 30% Within.

According to formula (3) calculate the relative retention time (RRT).

RRT = (3)

Where.

iRT - retention time of test compound, min;

isRT - Internal standard retention time, min.

According to the formula (4) calculate the auxiliary qualitative ion and quantitative ion peak area ratio (Q).

Where.

Aq - Auxiliary Qualitative Ion peak area;

At - Quantitative ion peak area.

9.2 Quantitative analysis According to the quantitative ion peak area, using internal standard method. Quantitative ions, the internal standard of the target compound see Appendix B.

9.3 Results Calculation the mass concentration () of the target compound in ambient air is calculated according to equation (5), using the average relative response factor in the sample the mass concentration of phthalates (i) is calculated according to equation (6).

Vx-=) (0 (5)

is i

i is

RRF A

x= x (6)

Where.

- concentration of target compound in ambient air, µg/m3;

i - the concentration of the target compound in the sample obtained from the mean relative response factor or standard curve, µg/ml;

0 - the mass concentration of the target compound in the laboratory blank, whichever is the blank mean, µg/ml;

V - sample volume concentrated volume, ml;

sV - Total volume sampled in the standard state (101.325 kPa, 273 K), m 3;

iA - Quantum ion peak area of the target compound in the sample.

9.4 results indicated when the concentration of phthalates in ambient air is greater than or equal to 1.00 µg/m3, the result retains three significant figures; for less than 1.00 µg/m3, the result is retained to the third decimal place.

10 precision and accuracy

10.1 Precision

Six laboratories added uniform samples of 4.0 µg, 20.0 µg and 36.0 µg to the blank (equivalent to 0.028 µg/m3 for air samples, 0.139 µg/m3 and 0.250 µg/m3) (n = 6). The relative standard deviations in the laboratory ranged from 2.0% to 14%, from 2.6% to 13% and 2.9% ~ 12% respectively. The relative standard deviations (RSDs) were 3.0% ~ 16%, 3.3% ~ 7.9% and 4.4% ~ 12% 0.003 µg/m3 to 0.007 µg/m3, 0.017 µg/m3 to 0.025 µg/m3, and 0.035 µg/m3 to 0.046 µg/m3. The reproducibility limits were 0.004 µg/m3 to 0.012 µg/m3, 0.024 µg/m3 to 0.037 µg/m3, and 0.042 µg/m3 to 0.083 µg/m3. See Appendix C for details.

10.2 Accuracy

Six laboratories to extract the actual sample concentrate as a unified sample spiked recovery (n = 6), the standard addition of 10.0 µg (phase when the air sample was 0.069 µg/m3), the spiked recoveries ranged from 66.9% to 113%, and the final spike recoveries ranged from 73.8% ± 7.6% 106% ± 19%. See Appendix C for details.

11 Quality Assurance and Quality Control 11.1 blank no more than 20 samples per batch, with at least 2 on-site blank and 2 laboratory blank, blank phthalates content not exceeding Over the lower limit of measurement, the relative double deviation of parallel does not ex...