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HJ 643-2013: Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography/mass method
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Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography/mass method
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HJ 643-2013
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PDF similar to HJ 643-2013
Standard similar to HJ 643-2013 HJ 644 HJ 662 HJ 298 HJ 950 HJ 642 Basic data | Standard ID | HJ 643-2013 (HJ643-2013) | | Description (Translated English) | Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography/mass method | | Sector / Industry | Environmental Protection Industry Standard | | Classification of Chinese Standard | Z13 | | Classification of International Standard | 13.030.10 | | Word Count Estimation | 25,211 | | Quoted Standard | HJ/T 20; HJ/T 299; HJ/T 300 | | Regulation (derived from) | ?Ministry of Environmental Protection Announcement 2013 No. 6 | | Issuing agency(ies) | Ministry of Ecology and Environment | | Summary | This standard specifies the determination of volatile organic compounds in solid waste headspace/gas chromatography-mass spectrometry. This standard is applicable to solid waste solid waste leachate in 36 kinds of measurement and volatile organic compound | HJ 643-2013: Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography/mass method
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Solid waste.Determination of volatile organic compounds.Headspace-gas chromatography/mass method
National Environmental Protection Standard of the People's Republic
Determination of volatile organic compounds in solid waste
Headspace/gas chromatography-mass spectrometry
Solid waste -Determination of volatile organic compounds-
Headspace-gas chromatography/mass method
Published on.2013-01-21
2013-07-01 Implementation
release
Ministry of Environmental Protection
Content
Foreword. II
1 Scope..1
2 Normative references..1
3 Terms and Definitions.1
4 principle of the method..2
5 reagents and materials. 2
6 instruments and equipment.3
7 samples.3
8 Analysis steps..4
9 Results calculation and representation..7
10 Precision and Accuracy..9
11 Quality Assurance and Quality Control 9
12 Waste treatment 11
13 Notes 11
Appendix A (informative) target detection limit and lower limit of measurement 12
Appendix B (informative) Determination of target compounds. Reference parameters. 15
Appendix C (informative) method of precision and accuracy. 17
Foreword
To implement the Environmental Protection Law of the People's Republic of China and the Law of the People's Republic of China on the Prevention and Control of Environmental Pollution by Solid Waste
This standard is formulated to protect the environment, protect human health, and regulate the determination of volatile organic compounds in solid waste.
This standard specifies headspace/gas chromatography-mass spectrometry for the determination of volatile organic compounds in solid waste.
This standard is the first release.
Appendix A of this standard is a normative appendix, and Appendix B and Appendix C are informative appendices.
This standard was formulated by the Science and Technology Standards Department of the Ministry of Environmental Protection.
This standard is mainly drafted by. Anshan Environmental Monitoring Center Station, Environmental Protection Institute of the Ministry of Environmental Protection.
This standard is verified by. Liaoning Provincial Environmental Monitoring Experimental Center, Shenyang Environmental Monitoring Center Station, Dalian Environmental Monitoring
Center, Harbin Environmental Monitoring Center Station, Fushun Environmental Monitoring Center Station and Liaoyang Environmental Monitoring Center Station.
This standard was approved by the Ministry of Environmental Protection on January 21,.2013.
This standard has been implemented since July 1,.2013.
This standard is explained by the Ministry of Environmental Protection.
Determination of volatile organic compounds in solid wastes by headspace/gas chromatography-mass spectrometry
Warning. The internal standard, substitute and standard solution used in the test are volatile toxic compounds. The preparation process should be
Operation in the fume hood; the sample preparation process should fully consider whether it is toxic or hazardous solid waste;
Wear protective gear to avoid contact with skin and clothing.
1 Scope of application
This standard specifies headspace/gas chromatography-mass spectrometry for the determination of volatile organic compounds in solid waste.
This standard applies to the determination of 36 volatile organic compounds in solid waste and solid waste leachate. If you pass the verification
The standard is also applicable to the determination of other volatile organic compounds.
When the amount of solid waste sample is 2 g, the detection limit of 36 target compounds is 0.8 μg/kg~4 μg/kg.
Limit 4 μg/kg ~15 μg/kg. When the volume of solid waste leachate is 10 ml, the detection limit of 36 target compounds is 0.1.
Gg/L~0.3 μg/L, the lower limit of measurement is 0.4 μg/L~2 μg/L. See Appendix A for details.
2 Normative references
The contents of this standard refer to the following documents or their terms. For undated references, the valid version is appropriate.
Used in this standard.
HJ/T 20 Technical Specifications for Sampling and Sample Preparation of Industrial Solid Waste
HJ/T 299 solid waste leaching toxicity leaching method sulfuric acid nitric acid method
HJ/T 300 solid waste leaching toxicity leaching method acetic acid buffer solution method
3 Terms and definitions
The following terms and definitions apply to this standard.
3.1 internal standards
Refers to a substance that is not contained in the sample but has similar physicochemical properties to the target to be tested. Usually added before sample analysis
In, for the quantification of the target.
3.2 surrogate standards
Refers to a substance that is not contained in the sample but has similar physicochemical properties to the target to be tested. Generally in sample extraction or other
Before the pretreatment, the recovery rate can be used to evaluate the influence of the sample matrix and the sample processing process on the analysis results.
3.3 matrix spiked spike
Refers to the addition of a known amount of the target to be tested to the sample. It is used to evaluate the recovery of the target and the matrix effect of the sample.
3.4 Calibration verification standards
Refers to a standard solution with a concentration near the midpoint of the calibration curve to confirm the validity of the calibration curve.
3.5 Shipping Blank Trip Blank
10 ml matrix modifier and 2.0 g quartz sand were placed in the headspace bottle for sealing before sampling, taking them to the sample
on site. When the sample is not opened, it will be shipped back to the laboratory with the sample, and the experiment will be carried out according to the same analysis steps as the sample.
Check if the sample is contaminated during transportation.
3.6 full program blank whole program blank
10 ml matrix modifier and 2.0 g quartz sand were placed in the headspace bottle for sealing before sampling, taking them to the sample
on site. Simultaneously open and seal with the sample vial, then transport it back to the laboratory with the sample, following the same analytical steps as the sample
An experiment is performed to check whether the entire process from sample collection to analysis is contaminated.
4 Principle of the method
Under certain temperature conditions, the volatile components in the sample in the headspace bottle volatilize into the liquid space to generate vapor pressure.
The liquid-solid three-phase reaches the thermodynamic dynamic equilibrium. The volatile organic compounds in the gas phase are separated by gas chromatography and then mass spectrometer
Detection. Qualitative by comparison with standard material retention times and mass spectra, quantified by internal standard method.
5 reagents and materials
Unless otherwise stated, chromatographically pure reagents that meet national standards were used for the analysis.
5.1 Experimental water. double distilled water or water prepared by pure water equipment. Need to pass the blank test before use, confirm
No interference peaks appeared in the retention time interval of the target compound or the target concentration therein was below the method detection limit.
5.2 Methanol (CH3OH). Chromatographic grade, pass the test before use to confirm the concentration of target compound or target compound
Below the method detection limit.
5.3 Sodium chloride (NaCl). excellent grade pure
In a muffle furnace (or box furnace), burn at 400 °C for 4h, place in a desiccator and cool to room temperature, transfer to the ground glass
Store in a glass bottle.
5.4 Phosphoric acid (H3PO4)). excellent grade pure.
5.5 Glacial acetic acid (CH3COOH). excellent grade pure.
5.6 Sodium hydroxide (NaOH). excellent grade.
5.7 sodium hydroxide solution. c (NaOH) = 1 mol/L
Weigh 40 g of sodium hydroxide (5.6), add to the beaker, and add a small amount of experimental water (5.1) to dissolve it.
Transfer to a 1 L volumetric flask and bring up to volume.
5.8 Extractant
5.8.1 Extracting agent 1. Measure 5.7 ml of glacial acetic acid to 500 ml of experimental water (5.1), add 64.3 ml of sodium hydroxide solution
(5.7), dilute to 1L with water. The pH of the solution after preparation should be 4.93 ± 0.05.
5.8.2 Leaching agent 2. Experimental water (5.1).
5.9 Matrix modifier
Measure 500 ml of experimental water (5.1), add a few drops of phosphoric acid (5.4) to adjust pH ≤ 2, add 180 g of sodium chloride (5.3),
Dissolve and mix. Store at 4 °C for 6 months.
5.10 Standard stock solution. ρ=1000 mg/L～5000 mg/L
Standard certified solutions can be purchased directly or in standard materials.
5.11 Standard use solution. ρ=10 mg/L～100 mg/L.
Volatile targets such as dichloromethane, trans-1,2-dichloroethylene, 1,2-dichloroethane, cis-1,2-dichloroethylene and chloroacetate
Standard intermediates such as olefins must be prepared separately, and the storage period is usually one week. The standard use solution of other targets is stored in compact.
The shelf life is one month or prepared according to the manufacturer's instructions.
5.12 Internal standard solution. ρ=250 mg/L
Fluorobenzene, chlorobenzene-d5 and 1,4-dichlorobenzene-d4 were selected as internal standards. A certified standard solution can be purchased directly.
5.13 Alternative standard solution. ρ=250 mg/L
Toluene-d8 and 4-bromofluorobenzene were used as substitutes. A certified standard solution can be purchased directly.
5.14 4-bromofluorobenzene (BFB) solution. ρ=25 mg/L
The certified standard solution can be purchased directly or can be prepared with a high concentration standard solution.
5.15 Quartz sand. 20 mesh ~ 50 mesh. Before use, it is necessary to pass the test to confirm that the concentration of the target compound or target compound is lower than
Method detection limit.
5.16 Carrier gas. high-purity helium (≥99.999%), deoxidized by deoxidizer and dehydrated by molecular sieve.
Note 1. All the above standard solutions are treated with methanol as the solvent. The standard solution after preparation or unsealing should be placed in a compact bottle, and protected from light under 4 °C.
Save, the shelf life is generally 30d. Recover to room temperature and mix before use.
6 Instruments and equipment
6.1 Gas Chromatograph. Capillary split/splitless inlet for temperature programming.
6.2 Mass Spectrometer. Electron Bombardment (EI) Ionization Source with 70 eV, NIST Mass Spectrometry Library, Manual/Automatic Tuning, Number
According to acquisition, quantitative analysis and library search and other functions.
6.3 Capillary column. 60 m × 0.25 mm × 1.4 μm (6 % nitrile propyl, 94 % dimethylpolysiloxane fixative),
Other equivalent capillary columns can also be used.
6.4 Headspace Sampler. with headspace bottle, gasket (PTFE/silicone or PTFE/butyl rubber), cap
(screw cap or gland used at one time).
6.5 Zero-Headspace Extraction Vessel. 500-600 ml for leaching in the sample
Hairy substance.
6.6 flip-type oscillator. speed is 30±2 r/min
6.7 Reciprocating Oscillator. The oscillation frequency is 150 times/min to fix the headspace bottle.
6.8 Ultrapure water preparation instrument or sub-boiling distiller.
6.9 pH meter. Accuracy is ±0.05.
6.10 Balance. Balance with an accuracy of 0.01 g.
6.11 Microinjectors. 5 μl, 10 μl, 25 μl, 100 μl, 500 μl, 1000 μl.
6.12 Brown compact bottle. 2 ml with Teflon liner and solid screw cap.
6.13 Disposable Pasteur glass pipettes.
6.14 Sampling bottle. 60 ml or 250 ml, threaded brown glass bottle with Teflon septa.
6.15 Sampling equipment. shovel and stainless steel medicine spoon.
6.16 Portable refrigerator. 20 L in volume and 4 °C below temperature.
6.17 Common instruments and equipment used in general laboratories.
7 samples
7.1 Sample collection and preservation
Collect and store solid waste samples in accordance with HJ/T 20 regulations. Tool for collecting samples applied to metal
The product should be purified before use. Samples can be taken at the sampling site using portable instruments for volatile organic determination
Primary screening with high and low concentration. At least 3 parallel samples should be collected for all samples.
Use a shovel or a medicine spoon to collect the sample into the vial (6.12) as soon as possible and fill it as much as possible. Quickly remove sample vial
The sample adhered to the grain and the outer surface, and the sample bottle is sealed. Put it in a portable freezer and bring it back to the lab.
Note 2. When the concentration of volatile organic compounds in the sample is greater than 1000 μg/kg, the sample is considered to be a high content sample.
Note 3. Do not stir solid waste during sample collection to avoid volatilization of organic matter in solid waste. Sampling personnel must do a good job
Work.
7.1.2 Preservation of samples
Samples should be analyzed as soon as they are sent to the laboratory. If it cannot be analyzed immediately, it should be sealed and stored below 4 °C, and the shelf life is not
More than 14 days. The sample storage area should be free of organic interference.
7.2 Preparation of samples
7.2.1 Low-volume samples of solid waste
Remove the sample vial from the laboratory. After returning to room temperature, weigh 2g of the sample into the headspace bottle and quickly move it into the top empty bottle.
Add 10 ml matrix modifier (5.9), 1.0 μl substitute (5.13) and 2.0 μl internal standard (5.12), immediately sealed, vibrating
The oscillation on the vortex was oscillated at a frequency of 150 times/min for 10 min, to be tested.
7.2.2 High-volume samples of solid waste
If the preliminary screening of volatile organic compounds at the site is high or low, the determination result is greater than 1000 μg/kg.
High content sample. High-content samples were prepared as follows, and the vials for high-content sample testing were removed and allowed to return to room temperature.
Weigh 2 g of sample into a headspace bottle, quickly add 10 ml of methanol (5.2), seal, and 150 on the shaker (6.7)
The frequency of the second/min is oscillated for 10 min. After standing to settle, remove about 1 ml of extract with a disposable Pasteur glass pipette.
In a 2 ml brown glass bottle, the extract can be centrifuged if necessary. The extract can be stored in a refrigerator at 4 ° C.
The shelf life is 14 days.
After returning the extract to room temperature before analysis, add 2.0 g of quartz sand (5.15), 10 ml to an empty headspace vial.
Matrix modifier (5.9) and 10 μl to 100 μl methanol extract. Add 2.0 μl of internal standard (5.12) and substitute (5.13),
Immediately sealed and oscillated at 150 times/min on the oscillator (6.7) for 10 min, to be tested.
Note 4. If the concentration of the target compound in the methanol extract is high, it can be appropriately diluted by adding methanol.
Note 5. If the concentration value is too low or not detected by the high content method, the sample should be re-analyzed using the low content method.
7.2.3 Solid waste leachate sample
A solid waste leachate sample was prepared by leaching a method of performing HJ/T 299 or HJ/T 300. Take 10 ml of leachate and move in
In the headspace vial, add 1.0 μl of the replacement (5.13) and 2.0 μl of the internal standard solution (5.12) and immediately seal and test.
7.3 Preparation of blank samples
7.3.1 Low-volume blank sample of solid waste
Replace the sample with 2.0 g quartz sand (5.15) and prepare a low content blank sample according to the procedure of 7.2.1.
7.3.2 Solid waste high content blank sample
Replace the high-content solid waste sample with 2.0 g quartz sand (5.15) and prepare a high-content blank sample according to the procedure in 7.2.2.
7.3.3 Blank sample of solid waste leachate
According to the extraction method of HJ/T 299 or HJ/T 300, put the extractant (5.8) in the headspace bottle and add 1.0 μl
Substance (5.13) and 2.0 μl internal standard use solution (5.12), immediately sealed and tested.
8 Analysis steps
8.1 Instrument Reference Conditions
Different working conditions of different types of headspace preparation instrument, gas chromatograph and mass spectrometer are different, and should be in accordance with the instructions for use of the instrument.
The book is operated. The recommended reference conditions for this standard are as follows.
8.1.1 Headspace Sampler Reference Conditions
Heating equilibrium temperature 60 °C ~ 85 °C; heating equilibrium time 50 min; sampling needle temperature 100 ° C; transmission line temperature
110 ° C, the transmission line is deactivated, quartz capillary column with an inner diameter of 0.32mm; pressure equilibrium time 1 min;
The injection time was 0.2 min; the needle setting time was 0.4 min; the headspace bottle pressure was 23 psi.
8.1.2 Gas Chromatograph Reference Conditions
Temperature programmed. 40 °C (for 2 min) 8 °C/min 90 °C (for 4 min) 6 °C/min.200 °C (keep
15 min). Inlet temperature. 250 °C. Interface temperature. 230 °C. Carrier gas. helium; inlet pressure. 18 psi. Enter
Sample mode. split injection, split ratio. 5.1.
8.1.3 Mass Spectrometer Reference Conditions
Scanning range. 35 amu~300 amu. Scan speed. 1 sec/scan. Ionization energy. 70 eV. Ion source temperature.
230 °C. Quadrupole temperature. 150 °C. Scan mode. full scan (SCAN) or selective ion (SIM) scan.
8.2 Calibration
8.2.1 Instrument performance check
The GC/MS system must perform an instrument performance check before daily analysis. Pipette 2 μl of BFB solution (5.10)
Direct injection through the GC inlet and analysis by GC/MS. The critical ion abundance of BFB obtained by GC/MS system should be
Meet the criteria specified in Table 1, otherwise some parameters of the mass spectrometer need to be adjusted or the ion source cleaned.
Table 1 4-bromofluorobenzene ion abundance standard
Mass-to-charge ratio ion abundance standard mass-to-charge ratio abundance standard
95 base peak, 100% relative abundance 175 mass 174 5% to 9%
96% 95% 5% to 9% 176 Quality 95% to 105% 174
173 is less than 25% of mass 174 177 is 5% to 10% of mass 176
174 is greater than 50% of mass 95
8.2.2 Drawing of the calibration curve
(1) Determination of the calibration curve of solid waste
Add 2 g of quartz sand (5.15), 10 ml of matrix modifier (5.9) to the 5 top empty bottles, and then divide into each bottle.
Do not add a certain amount of standard use solution (5.11), the concentration of volatile organic compounds is 5, 10, 20, 50, 100 μg/L;
Add a substitute (5.13) to each headspace bottle and add 2.0 μl of the internal standard solution (5.12) to seal immediately.
The concentration of the calibration series is shown in Table 2. The prepared standard series sample was oscillated on the oscillator (6.7) at a frequency of 150 times/min.
For 10 min, analyze the samples from low to high concentrations, establish a calibration curve or calculate the average response factor. In this standard
The standard total ion chromatogram of 36 volatile organic compounds was analyzed and determined under the specified conditions, as shown in Figure 1.
Table 2 Calibration Series Concentration
Calibration series concentration (μg/L) Substitute concentration (μg/L) Internal standard concentration (μg/L)
1-chloroethylene; 2-1,1-dichloroethylene; 3-dichloromethane; 4-trans-1,2-dichloroethylene; 5-1,2-dichloroethane; 6-cis-1, 2-dichloroethylene; 7-
Chloroform; 8-1,1,1-trichloroethane; 9-carbon tetrachloride; 10,11-1,2-dichloroethanebenzene; internal standard 1-fluorobenzene; 12-trichloroethylene; -1,2-two
Chloropropane; 14-bromodichloromethane; alternative 1-toluene-d8; 15-toluene; 16-1,1,2-trichloroethane; 17-tetrachloroethylene; 18-dibromo-chloro
Methane; 19-1,2-dibromoethane; internal standard 2-chlorobenzene-d5; 20-chlorobenzene; 21-1,1,1,2-tetrachloroethane; 22-ethylbenzene; 23, 24 -m-xylene
P-xylene; 25,26-o-xylene styrene; 27-bromoform; alternative 2-4-bromofluorobenzene; 28-1,1,2,2-tetrachloroethane; 29-1, 2,3-trichloro
Propane; 30-1,3,5-trimethylbenzene; 31-1,2,4-trimethylbenzene; 32-1,3-dichlorobenzene; internal standard 3-1,4-dichlorobenzene- D4; 33-1,4-dichlorobenzene;
34-1,2-dichlorobenzene; 35-1,2,4-trichlorobenzene; 36-hexachlorobutadiene
Figure 1 36 volatile organic compounds standard total ion chromatogram
(2) Determination of calibration curve of solid waste leachate
Add 10 ml of extractant (5.8) to each of the 5 top empty bottles, and then add a certain amount of standard use to each bottle.
Liquid (5.11), the concentration of volatile organic compounds is 5, 10, 20, 50, 100 μg/L; respectively, and then to each headspace bottle
Add 0.2, 0.4, 0.8, 2.0, 4.0 μl of the replacement (5.13) and add 2.0 μl of the internal standard solution (5.12).
Seal immediately. According to the instrument reference conditions (8.1), the measurement is carried out sequentially from a low concentration to a high concentration. Establish a calibration curve or calculate a flat
Average response factor. The standard total ion chromatogram of 36 volatile organic compounds is determined under the conditions specified in this standard, as shown in Figure 1.
8.2.2.1 Establishing a calibration curve with an average relative response factor
The relative response factor (RRFi) of the target (or surrogate) in point i of the standard series, calculated according to formula (1)
Count.
ISi
ISi
i A
RRF ρ
ρ×=
(1)
In the formula.
RRFi--the relative response factor of the i-th target (or substitute) in the standard series;
Ai--the response value of the quantified ion of the i-th target (or substitute) in the standard series;
AISi--the ith point of the standard series corresponds to the target (or substitute) corresponding to the internal standard quantitation ion response value;
ρIS--the concentration of the internal standard in the standard series, 50 μg/L;
ρi--The mass concentration of the i-th target (or substitute) in the standard series, μg/L.
The average relative response factor RRF of the target (or substitute) is calculated according to formula (2).
RRF
RRF
I∑
== 1 (2)
In the formula.
RRF - the average relative response factor of the target (or substitute);
RRFi--the relative response factor of the i-th target (or substitute) in the standard series;
n--Standard series points.
The standard deviation of RRF is calculated according to formula (3).
)( 2
RRFRRF
SD
(3)
The relative standard deviation of RRF is calculated according to formula (4).
0×=
RRF
SDRSD (4)
The relative standard deviation (RSD) of the relative response factor (RRF) of the standard series of targets (or substitutes) should be less than
At 20%.
8.2.2.2 Drawing a calibration curve using least squares
The ratio of the response of the target compound to the corresponding internal standard is plotted on the ordinate, and the concentration ratio is plotted on the abscissa, which is established by least squares method.
Calibration curve. If the correlation coefficient of the established linear calibration curve is less than 0.990, a nonlinear fitting curve can also be used.
For line calibration, the curve correlation coefficient needs to be greater than or equal to 0.990. When using a non-linear calibration curve, at least 6 concentration points should be used
Perform calibration.
8.3 Determination
The prepared sample (7.2) was placed on a headspace sampler and measured according to the instrument reference conditions (8.1).
8.4 Blank test
The prepared blank sample (7.3) was placed on a headspace sampler and measured according to the instrument reference conditions (8.1).
9 Calculation and representation of results
9.1 Qualitative analysis of target compounds
The target is characterized by a relative retention time (or retention time) compared to the mass spectrum
9.2 Quantitative analysis of targets
The calculation is based on the response value of the first characteristic ion of the target and the internal standard. When the first characteristic ion of the target in the sample has
For interference, the second characteristic ion quantification can be used, see Appendix B for details.
9.2.1 Calculation of the mass concentration exρ of the target (or substitute) in the sample
9.2.1.1 Calculated using the average relative response factor
When the target (or substitute) is calibrated using the average relative response factor, the mass concentration of the target in the sample
Exρ is calculated according to formula (5).
RRFA
IS
ISx
Ex ×
×= ρρ (5)
In the formula.
Exρ - the mass concentration of the target (or substitute) in the sample, μg/L;
Ax -- the target (or substitute) quantified ion response value;
AIS - the response value of the internal standard quantitative ion corresponding to the target (or substitute);
ρIS - concentration of internal standard, μg/L;
RRF - The average relative response factor of the target (or surrogate).
9.2.1.2 Calculat...
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