HJ 866-2017Water quality. Determination of turpentine. Purge and trap/gas chromatography-mass spectrometry (English PDF)

1 Scope 1

2 Normative references 1 3 method principle 1

4 Reagents and materials

5 Instruments and equipment

6 Samples .2

7 Analysis Step 2

8 Results Calculation and Presentation 6

9 Precision and accuracy 7

10 Quality Assurance and Quality Control .8

11 Waste treatment .8

i Foreword

In order to implement the "Law of the People's Republic of China on Environmental Protection" and the "Law of the People's Republic of China on Prevention and Control of Water Pollution", protect the environment, Ensure human health, regulate the determination of turpentine in water, the development of this standard.

This standard specifies the determination of turpentine water purge/gas chromatography - mass spectrometry.

This standard is released for the first time.

This standard by the Environmental Protection Department of Environmental Monitoring Division and Science and Technology Standards Division to develop.

This standard was drafted. China Environmental Monitoring Station.

This standard verification unit. Beijing Environmental Protection Monitoring Center, Environmental Monitoring Center of Hebei Province, Zhejiang Province Environmental Monitoring Heart, Chongqing Ecological Environment Monitoring Center, Yangzhou Environmental Monitoring Center Station and Ningbo Environmental Monitoring Center.

This standard MEP approved on November 28, 2017.

This standard since January 1, 2018 come into operation.

This standard is interpreted by the MEP.

Determination of quality of turpentine water purge/gas chromatography - mass spectrometry Warning. The reagents and standard solutions used in this method are volatile and toxic compounds. The preparation process should be done in a fume hood Conduct, should be required to wear protective equipment, avoid contact with skin and clothing.

1 scope of application this standard specifies the determination of turpentine water purge/gas chromatography - mass spectrometry.

This standard applies to the determination of turpentine in surface water, groundwater, domestic sewage and industrial waste water.

When the sample volume is 5 ml, the method detection limit of turpentine is 0.5 µg/L and the lower limit of determination is 2.0 µg/L.

2 Normative references this standard references the following documents in the terms. For undated references, the effective version applies to this book standard.

HJ/T 91 Technical Specifications for Surface Water and Sewerage Monitoring HJ/T 164 Groundwater Environmental Monitoring Technical Specifications 3 method principle the turpentine in water is purged by high-purity helium (or nitrogen) and then adsorbed to the trap. The trap is rapidly heated and purified with high purity After the helium (or nitrogen) is backflushed, the components that have been thermally desorbed are separated by gas chromatography and detected by mass spectrometry. According to pine the main components of oil-saving alpha-pinene and beta-pinene retention time and mass spectrometry and standard material than the qualitative, internal standard method.

4 Reagents and materials Unless otherwise specified, the analysis of the use of analytical reagents in line with national standards, the experimental water is not pure water.

4.1 Methanol (CH3OH). Chromatographic purity.

4.2 Turpentine (C10H16) standard solution. rho = 500 µg/ml, the solvent is methanol, a certified turpentine mixed standard solution on the market.

4.3 turpentine standard solution. rho = 20.0 µg/ml.

Pipette 400 µl of turpentine standard solution (4.2) into a 10 ml volumetric flask, dilute with methanol (4.1), transfer to poly Tetrafluoroethylene liner Spiral bottle cap brown reagent bottles, stored at 0 ~ 4 C can be stored for one month.

4.4 Internal standard solution. 1,2-dichlorobenzene-d4, rho =.2000 µg/ml, methanol solvent, a certified standard solution on the market.

4.5 Internal standard solution. rho = 20.0 µg/ml.

2 Pipet 100 µl of the internal standard solution (4.4) into a 10 ml volumetric flask and dilute to volume with methanol (4.1) and transfer to polytetrafluoroethylene Fluoro ethylene liner screw cap brown reagent bottle, at 0 ~ 4 C can be stored for one month.

4.6 4-Bromofluorobenzene (BFB). rho = 25 µg/ml, a commercially available certified standard solution.

4.7 Helium, purity >=99.999%.

4.8 nitrogen, purity >=99.999%.

5 instruments and equipment

5.1 Gas Chromatography - Mass Spectrometer. Chromatography section with split/splitless inlet for programmable warming. Part of the mass spectrum with electron impact (EI) Ionization source, with manual/automatic tuning, data acquisition, quantitative analysis and library search and other functions.

5.2 Purge and Trap. with 5 ml purge. Trap tube using 1/3 Tenax, 1/3 silica gel, 1/3 activated carbon mixed adsorbent or other equivalent adsorbent.

5.3 Column. quartz capillary column, 30 m × 0.25 mm, film thickness 1.4 m, 6% of stationary phase nitrile propyl phenyl/94% dimethyl Polysiloxane, or other equivalent capillary column.

5.4 Vials. 40 ml wide-mouth glass vials with Teflon-lined screw cap.

5.5 Airtight syringe. 5 ml.

5.6 Microprojectors. 10 µl, 25 µl, 50 µl and 250 µl.

5.7 General laboratory equipment and equipment.

6 samples

6.1 sample collection Collect samples according to HJ/T 91 and HJ/T 164, and slowly introduce the sample into the vial (5.4) along the wall until Full bottles should minimize turpentine escape due to agitation and avoid introducing air bubbles into the sampling bottle.

Note. The sample can not add acid.

6.2 Sample preservation Samples collected after 1 ~ 5 C refrigerated transport. Shipped back to the laboratory as soon as possible after analysis, or should be 1 ~ 5 C stored in refrigeration, 2 d Analysis is completed.

7 Analysis steps

7.1 Instrument reference conditions

7.1.1 Purge and Trap Reference Conditions

3 Sample volume 5.0 ml Purge temperature. 40 ° C Purge flow. 40 ml/min Purge time. 11 min Desorption temperature.

180 ° C; Desorption time. 1 min; Baking temperature. 190 ° C; Baking time. 10 min. Other parameters refer to the use of the instrument Set the Ming book.

7.1.2 GC reference conditions Program temperature. 38 C for 1.0 min, with 5 C/min rose to 150 C, and then 25 C/min rose to 230 C, Paul Hold 3.0 min; Inlet temperature. 230 ° C; Carrier gas flow. 1.0 ml/min; Injection mode. Split injection (split ratio 25. 1).

7.1.3 Reference conditions for mass spectrometry analysis Electron impact source. EI source; Ionization energy. 70 eV; Ion source temperature. 230 ° C; Transmission line temperature. 250 ° C; Scanning Method. Full scan; Scanning range. 35 ~ 300 amu; Solvent delay time. 6.0 min; Other parameters refer to instrument usage Set the Ming book.

Note. In order to improve the sensitivity, the method of selective ion scan can also be used for the analysis. For the selection of the quantitative ions and the auxiliary ions, see Table 2.

7.2 Calibration

7.2.1 instrument performance check Gas chromatograph - mass spectrometers must perform instrument performance checks before analyzing samples. Pipette 2 µl of 4-Bromofluorobenzene (4.6) through Inject directly through the gas chromatographic inlet or use a volumetric flask to prepare a 4-Bromofluorobenzene solution at a concentration of 25.0 µg/L, the sample was desorbed and trapped and analyzed by Gas Chromatography-Mass Spectrometer. Analysis conditions refer to 7.1. The resulting 4-Bromofluorobenzene key ions Abundance should meet the requirements in Table 1, otherwise the mass spectrometer parameters need to be adjusted or cleaned ion source.

Table 1 4-Bromofluorobenzene key ion abundance criteria

Mass ion abundance standard mass ion abundance standard 50% by mass 95% ~ 40% 174 more than 95% by mass 95%

95 Base Peak, 100% Relative Abundance 175 5% to 9% of mass 174

96 95% to 95% of mass 95 176% to 95% to 95%

173 Less than 2% of mass 174 177 5% to 10% of mass 176

7.2.2 Calibration curve drawing Pipette a certain amount of turpentine standard solution (4.3) quickly added to the experimental water with 50 ml volumetric flask, set to volume, preparation of low, high concentration of two series. Low-concentration series were 2.0 µg/L, 4.0 µg/L, 10.0 µg/L, 20.0 µg/L, 40.0 µg/L, take turpentine standard solution (4.3) were 5.0 µl, 10.0 µl, 25.0 µl, 50.0 µl, 100 µl;

High concentration series of 40.0 µg/L, 100 µg/L,.200 µg/L, 400 µg/L, 1.00 × 103 µg/L, the solutions (4.3) were 0.10 ml, 0.25 ml, 0.50 ml, 1.00 ml, 2.50 ml, respectively. Use a 5 ml airtight syringe Pipette 5.0 ml of the standard solution and add 5.0 µl of the standard internal standard solution (4.5), according to the reference conditions of 7.1, from the low concentration

4 To high concentration followed by determination, record the standard series of target and internal standard retention time, the quantitative ion response.

In practice, depending on the concentration range of turpentine in the sample to be tested, a series of low concentration calibration curves or high Concentration series calibration curve. Under normal circumstances, the surface water, groundwater, domestic sewage test selected 2.0 ~ 40.0 g/L Standard series, industrial wastewater test based on the concentration range may choose to formulate low concentration or high concentration standard series.

Note 1. If using a purge trap with an autosampler, the procedure described above can be performed according to the instrument instructions.

Note 2. The calibration series solutions are not stable and therefore need to be ready for use.

Note 3. The purge and traps should be baked after each start-up and before shutdown to ensure that the system is not contaminated.

Under the chromatographic conditions specified in this standard, the total ion chromatogram of the target compound is shown in Figure 1.

1-alpha-pinene; 2-beta-pinene; 3-1,2-dichlorobenzene-d4 (internal standard)

Figure 1 Total ion current plot of target compounds

7.2.2.1 Calculation method of average relative response factor the relative response factor (RRFi) of turpentine in the calibration series point i is calculated according to formula (1).

ISi

RRF

x=) (21 (1)

Where. RRFi - the relative response factor for the ith turpentine in the calibration series;

A1i - Response values of alpha-pinene quantitation ions at point i in the calibration series;

A2i - the response value of the ith pinene-enriched ion in the calibration series;

AISi - Calibration value of the i-th internal standard quantitation ion in the calibration series;

- Concentration of internal standard in the calibration series, µg/L;

- Concentration of turpentine at point i in the calibration series, µg/L.

1 6 .0 0 1 7 .0 0 1 8 .0 0 1 9 .0 0 2 0 .0 0 2 1 .0 0 2 2 .0 0 2 3 .0 0 Time - - > Abundance TIC. Turpentine 5 0 ppb - 5 .D \\ data .ms Time (min)

5 Turpentine average relative response factor RRF, calculated according to equation (2).

RRF

RRF

Where. RRF - turpentine average relative response factor;

RRFi - Relative response factor for point i turpentine in the calibration series;

n - Calibration series points.

The standard deviation of the RRF is calculated according to equation (3).

RRFRRF

Where. SD - standard deviation of RRF;

RRF - turpentine average relative response factor;

RRFi - Relative response factor for point i turpentine in the calibration series;

n - Calibration series points.

The relative standard deviation of RRF is calculated according to equation (4).

RRF

RSD (4)

Where. RSD - RRF relative standard deviation;

SD - standard deviation of RRF;

RRF - Turpentine average relative response factor.

7.2.2.2 Calibration curve method Taking the ratio of turpentine concentration to internal standard concentration as abscissa, the sum of the response values of alpha-pinene and beta-pinene quantitative ion and Standard quantitative ion response value of the ratio of the vertical axis, draw the calibration curve.

7.3 Determination

After the sample is returned to room temperature, a 5.0 ml sample is aspirated with a gas-tight syringe and 5.0 µl of an internal standard is added to the sample with liquid (4.5), the sample concentration of 20.0 µg/L internal standard, the sample quickly injected into the purge tube, according to the instrument reference conditions (7.1) using the calibration curve of 7.2.2. The autosampler purge trap can refer to the instrument instructions Make.

NOTE 1 After analysis of a high concentration sample, one or more blank samples should be analyzed for cross-contamination.

6 Note 2. Determination of industrial wastewater samples, if the turpentine concentration is higher, it is recommended to dilute before measuring.

7.4 Blank test

Replace the sample with the experimental water, and perform the blank test according to the same measurement procedure (7.3) as the sample.

8 results calculated and said

8.1 Qualification of the target compound According to the sample turpentine main components alpha-pinene and beta-pinene retention time, mass spectrometry, fragment ion mass ratio and abundance Degree and other information and qualitative comparison of the standard material. The calibration solution should be repeatedly analyzed to obtain the mean value of the retention time of the target the standard deviation of ± 3 times the retention time is the retention time window, and the retention time of the target in the sample should be within its range.

All ions with a relative abundance above 30% of the target's standard spectrum should exist in the sample's spectrum, and the sample's spectrum and the standard spectrum of the above characteristic ions relative abundance deviation should be within ± 30%.

8.2 Quantification of the target compound After the qualitative identification of the target compound, according to the quantitative ion response value, calculated by internal standard method. Quantitative ion of target See Table 2 for auxiliary ions.

Table 2 Quantitative ions and auxiliary ions for compounds List

No. Target Type Quantum ion-assisted ion 1 alpha-Pinene Target Compound 93 92,91,77 2 beta-Pinene Target Compound 93 41,69,39 3 1,2-Dichlorobenzene-d4 Internal standard 150 152,115

8.2.1 Quantified by the average relative response factor when the target compound is calculated using the average relative response factor, the mass concentration of turpentine in the sample, x, (5) to calculate.

RRFA

fAA

ISxx

xx= ) (21 (5)

Where. x - sample mass turpentine concentration, µg/L;

Response of A1x - alpha-pinene to quantified ions;

A2x - beta-pinene quantitative ion response value;

AIS - Internal standard quantitative ion response value;

IS - mass concentration of internal standard, µg/L;

7RRF - average relative response factor for turpentine;

f - dilution factor.

8.2.2 Quantitative calibration curve when the target compound is quantified by the calibration curve method, based on the sum of the quantitative ion response values of alpha-pinene and beta-pinene, the mass concentration of turpentine is obtained directly from the calibration curve. The concentration of turpentine in the sample, x, is calculated according to equation (6).

fx x= 1 (6)

Where. x - turpentine mass concentration in the sample, µg/L;

1 - turpentine concentration obtained from the calibration curve, µg/L;

f - dilution factor.

8.3 results indicated when the determination results 9 precision and accuracy

9.1 Precision

Six laboratories performed uniform blank spiked samples with turpentine concentrations of 5.0 µg/L, 100 µg/L and 400 µg/L, respectively the relative standard deviations in the laboratory were 2.1% -8.9%, 2.4% -6.5% and 3.3% -7.9% respectively. The relative standard deviation the standard deviations were 12%, 5.4% and 6.7% respectively. The repeatability limits were 0.6 µg/L, 12.6 µg/L and 49.5 µg/L respectively.

The current limits were 1.5 µg/L, 18.2 µg/L and 82.6 µg/L, respectively.

Six laboratories separately measured turpentine concentrations of 5.0 µg/L and.200 µg/L of surface water samples. The laboratory phase the standard deviations were 2.1% -4.4% and 3.0% -8.6% respectively. The relative standard deviations of the laboratories were 9.6% and 12%, respectively.

The repeatability limits were 0.4 µg/L and 27.8 µg/L, respectively. The reproducibility limits were 1.3 µg/L and 70.8 µg/L, respectively.

Six laboratories separately measured the samples of domestic sewage with turpentine concentrations of 50.0 µg/L and 400 µg/L, and the laboratories the relative standard deviations were 2.4% ~ 6.3% and 1.2% ~ 9.8% respectively. The relative standard deviations (RSDs) were 8.7% and 8.3%, respectively.

The repeatability limits were 6.5 µg/L and 51.5 µg/L, respectively. The reproducibility limits were 13.0 µg/L and 93.9 µg/L, respectively.

6 laboratories respectively, the turpentine concentrations of 50.0 µg/L and 400 µg/L of industrial wastewater samples were measured, the laboratory the relative standard deviations (RSDs) were 1.7% -9.6% and 1.1% -8.7% respectively. The relative standard deviations (RSDs) were 11% and 15% respectively.

The repeatability limits were 8.2 µg/L and 52.5 µg/L, respectively. The reproducibility limits were 16.2 µg/L and 157 µg/L, respectively.

89.2 Accuracy

Six laboratories, respectively, spiked with turpentine concentrations of 5.0 µg/L,.200 µg/L of surface water samples were measured, plus the standard the yields were 76.0% -96.0% and 77.9% -112%, respectively. The final recoveries were 88.7% ± 17% and 95.6% ± 23%, respectively.

Six laboratories respectively spiked turpentine spiked at a concentration of 50.0 µg/L, 400 µg/L of domestic sewage samples were measured, the recoveries were 88.5% -110% and 77.3% -95.0%, respectively. The final recoveries of spiked samples were 95.6% ± 16% 87.4% ± 14%.

Six laboratories respectively measured the spiked industrial wastewater samples with spiked concentrations of 50.0 µg/L and 400 µg/L, the recoveries were 75.9% -106% and 71.1% -109%, respectively. The final recoveries of spiked samples were 91.6% ± 20% 89.2% ± 27%.

10 Quality Assurance and Quality Control

10.1 Instrument Performance Check Perform instrument performance checks prior to or within 24 h of each batch of sample analysis. The resulting 4-Bromofluorobenzene (4.6) key ions Abundance must all meet the criteria in Table 1.

10.2 Initial calibration the calibration curve requires a minimum of 5 concentration series and the correlation coefficient for the initial calibration curve should be >=0.995 or Relative Response Factor (RRF) the relative standard deviation (RSD) should be <= 20%, or should find the cause or redraw the calibration curve.

10.3 Continuous calibration Every 24 h analysis of the calibration curve intermediate concentration point, the measurement results and the actual concentration value of the relative deviation should be <= 20%, no You should look for the cause or redraw the calibration curve.

10.4 samples

10.4.1 A blank test shall be performed for every 20 samples or batches (<=20 batches/batch), the concentration of the target substance in the test result shall not be Method detection limit exceeded.

10.4.2 For each 10 samples or batches (<=10 batches/batch), one parallel sample and matrix shall be analyzed for spiking and parallel analysis the relative deviation of the standard compounds should be <= 30%, the matrix recovery rate should be between 70.0% ~ 120%.

11 Waste treatment

The waste produced by laboratories containing organic reagents should be collected and stored in a closed container, labeled, and labeled Sign, send a qualified unit of uniform treatment.