WO2022269763A1

WO2022269763A1 - Method for measuring phthalic-acid-ester- and bromine-based flame-retardant compound, and gas chromatography for use in said method

Info

Publication number: WO2022269763A1
Application number: PCT/JP2021/023636
Authority: WO
Inventors: 恭彦工藤
Original assignee: 株式会社島津製作所
Priority date: 2021-06-22
Filing date: 2021-06-22
Publication date: 2022-12-29
Also published as: CN117413180A; JPWO2022269763A1

Abstract

Provided is a method for measuring a phthalic-acid-ester- and bromine-based flame-retardant compound, said method including: a step 41 for heating a specimen that contains a subject compound belonging to at least one of phthalic acid esters, polybrominated biphenyls, and polybrominated diphenyl esters, and vaporizing the subject compound included in the specimen; a step 42 for adjusting an analysis column 14 to a temperature lower than the maximum temperature used when vaporizing the subject compound, the analysis column 14 having a separation column 142 provided with a securing phase 1421 for separating the subject compound in the interior thereof, and a guard column 141 provided integrally with the separation column at the inlet side of the separation column without using a connection component; a step 2 for introducing the vaporized subject compound into the analysis column 14; and a step 44 for detecting the subject compound flowing out from the separation column 142.

Description

Method for measuring phthalates and brominated flame-retardant compounds and gas chromatograph column for the method

The present invention relates to a method for measuring phthalate esters and brominated flame retardant compounds, and a gas chromatograph column used in carrying out the method.

Phthalates (di(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), and diisobutyl phthalate (DIBP)) and brominated flame retardants Certain polybrominated biphenyls (PBBs, molecular formula C ₁₂ H _(10-n) Br _n (1 ≤ n ≤ 10)) and polybrominated diphenyl ethers (PBDEs, molecular formula C ₁₂ H _{(10 -m)} Br _m O (1≤m≤10)) is designated as a regulated compound under the RoHS Directive, and is a phthalate that is allowed in parts such as resins contained in electrical and electronic products exported to Europe. Total contents of acid esters, PBBs, and PBDEs are defined respectively.

Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and pyrolyzer/thermal desorption-gas chromatography/mass spectrometry (Py-GC/MS) are used to measure phthalates, PBBs, and PBDEs in resin samples. /TD-GC/MS) method is used. In the Py-GC/MS method, a container containing a resin sample is introduced into a pyrolyzer and heated to thermally decompose the resin. PBDEs (hereinafter collectively referred to as "regulated compounds") are introduced into the gas chromatograph. In Py-GC/MS, the resin sample is heated, for example, to about 600°C. In the Py/TD-GC/MS method, a container containing a resin sample is introduced into a pyrolyzer and heated to a temperature below the temperature at which the resin thermally decomposes, thereby desorbing the regulated compounds contained in the resin from the resin. to the gas chromatograph. In Py/TD-GC/MS, the resin sample is heated, for example, to about 340°C.

In the Py-GC/MS method, not only regulated compounds but also compounds other than regulated compounds (contamination compounds) contained in resin thermal decomposition products and resin samples are introduced into the gas chromatograph. Also in the Py/TD-GC/MS method, thermal decomposition products generated by thermal decomposition of a part of the resin sample and contaminant compounds are introduced into the gas chromatograph. Since the temperature of the separation column when measuring these regulated compounds is lower than the temperature used to heat the resin sample with a pyrolyzer (e.g., about 300°C or less), some decomposition products and contaminant compounds of the resin sample adheres to and remains in the separation column, easily contaminating the inside of the separation column. If the inside of the separation column is contaminated, chromatogram peak tailing occurs when a regulated compound is measured, and measurement reproducibility and quantification accuracy deteriorate. Therefore, when the separation column deteriorates, it is necessary to cut off the deteriorated inlet portion or replace the separation column with a new one. A large number of resin parts are used in electrical and electronic equipment products, and it may be required to frequently measure the amount of regulated compounds contained in those resin parts. However, if the above operation is performed every time the separation column deteriorates, the efficiency of measurement will deteriorate. Therefore, it has been proposed to attach a guard column to the inlet of the separation column of the gas chromatograph to suppress contamination inside the separation column (for example, Non-Patent Documents 1 and 2). As a result, the life of the separation column can be lengthened, the frequency of the above operations can be reduced, and the measurement efficiency can be increased.

Non-Patent Document 1 describes that an insert tube is used to attach a guard column to a separation column in the following procedure. First, the guard column is inserted from one end of the insert tube, and the separation column is inserted from the other end. A ferrule is then placed on each end of the insert tube. Finally, the guard column and the separation column positioned inside the insert tube are fixed by attaching nuts to the outside of the ferrules positioned at both ends and crushing the ferrules. Thus, connecting the guard column described in Non-Patent Document 1 to the separation column requires a three-step work process, which takes time and effort. In addition, if the connection between the guard column and the separation column is not perfect, carrier gas and regulated compounds will leak, resulting in erroneous measurement results. The person who measures the content of regulated compounds for the purpose of inspecting resin products is not always skilled in such work, so there is a need for a technology that can more easily suppress the deterioration of separation columns. . Furthermore, in Non-Patent Document 1, a metal insert tube is used. As described in Non-Patent Document 3, the regulated compounds include those that are highly reactive with metals, and there is a gap between the guard column inserted in the insert tube and the separation column. Then, if a highly reactive regulated compound is adsorbed on the metal constituting the insert tube and then decomposed, the content of the regulated compound cannot be measured correctly.

Here, the case of vaporizing regulated compounds using a pyrolyzer was explained as an example. had the same problem as above.

The problem to be solved by the present invention is that it is possible to suppress the deterioration of the separation column without requiring complicated work, and to accurately measure phthalates and brominated flame retardants that are easily adsorbed and decomposed. To provide a method and a gas chromatographic column for use in carrying out the method.

The method for measuring phthalate esters and brominated flame retardant compounds according to the present invention, which has been made to solve the above problems,
heating a sample containing a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group to vaporize the target compound contained in the sample;
An analysis column having a separation column internally provided with a stationary phase for separating the target compound, and a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts. , adjusting the temperature to a temperature lower than the maximum temperature at which the target compound is vaporized,
introducing the vaporized target compound into the analysis column;
A target compound flowing out from the separation column is detected.

Another aspect of the present invention, which has been made to solve the above problems, is a gas chromatograph column used in carrying out a method for measuring phthalates and brominated flame retardant compounds,
a separation column provided with a stationary phase for separating a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group;
and a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts.

In the present invention, a column provided with a stationary phase for separating target compounds belonging to at least one of phthalates, polybrominated biphenyls, and polybrominated diphenyl ethers, and a An analysis column having the separation column and a guard column provided integrally is used. In the present invention, since the separation column and the guard column are integrally constructed without using connecting parts, there is no need to connect them, and the carrier gas or the target compound leaks from the connection between the two. The target compound is not adsorbed to the connecting member and decomposed. Therefore, deterioration of the separation column can be suppressed without requiring complicated work, and phthalate esters and brominated flame-retardant compounds, which tend to adhere to the separation column or decompose, can be measured correctly.

Principal part of a pyrolyzer-gas chromatography/mass spectrometer including an example of the gas chromatograph column of the present invention, which is used in an example of the method for measuring phthalates and brominated flame retardant compounds of the present invention Diagram. FIG. 4 is a diagram showing the configuration of a column in this embodiment; Graph showing the relationship between the length of the guard column and the flow rate of the carrier gas when the flow rate of the carrier gas is constant. Measurement conditions for phthalate esters and brominated flame retardant compounds in this example. An example of a relative sensitivity coefficient table in this embodiment. 1 is a flow chart showing a procedure in an embodiment of a method for measuring phthalates and brominated flame retardants according to the present invention. 4 is a flow chart showing the procedure in another example of the method for measuring phthalate esters and brominated flame retardant compounds according to the present invention. Measurement results confirming the effects of the measurement method and the chromatographic column for the phthalate esters and brominated flame retardant compounds of this example.

An embodiment of the method for measuring phthalates and brominated flame retardant compounds and the gas chromatograph column according to the present invention will be described below with reference to the drawings. In this example, using a pyrolyzer-gas chromatograph mass spectrometer (Py-GC-MS), phthalates and polybrominated biphenyls, which are brominated flame retardant compounds (polybrominated biphenyls, PBBs, molecular formula C ₁₂ H _(10-n) Br _n (1≦n≦10)) and polybrominated diphenyl ethers (PBDEs, molecular formula C ₁₂ H _(10-m) Br _m O(1≦m≦10)) The quantification is used to screen the sample to be analyzed. Hereinafter, these compounds are collectively referred to as regulated compounds. A sample to be analyzed in this embodiment is a resin product or the like subject to the RoHS Directive.

1. Configuration of Py-GC-MS FIG. 1 shows the main configuration of a pyrolyzer-gas chromatograph/mass spectrometer (Py-GC-MS) 1 used in the method for measuring a regulated compound in this example.

The Py-GC-MS 1 is roughly divided into a gas chromatograph section 10, a mass spectrometry section 20, and a control/processing section 30. The gas chromatograph unit 10 includes a sample vaporization chamber 11, a pyrolyzer 12 provided in the sample vaporization chamber 11, a carrier gas flow path 13 connected to the sample vaporization chamber, and an outlet of the sample vaporization chamber 11. A column 14 is provided. Column 14 is housed inside column oven 15 . The pyrolyzer 12 and the column 14 in the column oven 15 are each heated to a predetermined temperature by a heating mechanism (not shown).

FIG. 2 shows the structure of the column 14 (corresponding to the analysis column in the present invention) used in this example. Column 14 is composed of guard column 141 and separation column 142 . The guard column 141 is provided seamlessly and integrally with the separation column 142 on the side of the sample injection port of the separation column 142 . Both the guard column 141 and the separation column 142 are capillary tubes made of fused silica with an inner diameter of 0.25 mm. liquid phase) is provided. In the separation column 142 of this embodiment, 100% dimethylpolysiloxane with a film thickness of 0.1 μm is used as the stationary phase. A stationary phase other than dimethylpolysiloxane may be used to measure the controlled compound. Considering that the regulated compound in this example is a highly polar compound, it is preferable to use a nonpolar substance with a film thickness of 1.0 μm or less as the stationary phase. However, the film thickness is preferably 0.05 μm or more because it is necessary to desorb from the stationary phase by generating a certain degree of interaction with each regulatory compound.

Some conventionally used guard columns have a stationary phase inside. By providing the stationary phase inside the guard column, contaminants are more likely to be collected and less likely to reach the separation column, so that the separation column is less likely to be contaminated. On the other hand, however, both contaminants and the target compound are collected on the stationary phase of the guard column, so peak tailing is likely to occur when measuring the target compound. In this example, a guard column 141 without a stationary phase is used in order to prevent tailing of the peak of the regulated compound.

The length of the guard column 141 of this embodiment is 2 m, and the length of the separation column 142 is 15 m. The guard column 141 is used to prevent the separation column 142 from being contaminated by substances other than the regulated compounds (resin thermal decomposition products, contaminant compounds, etc.) released when the resin sample is heated by the pyrolyzer 12. . Since the temperature at which the column 14 is heated by the column oven 15 is lower than the temperature at which the pyrolyzer 12 is heated, these substances released from the pyrolyzer 12 are gradually cooled and adhere to the inner wall surface of the guard column 141 . If guard column 141 is shorter than 50 cm, these substances can easily enter separation column 142 . On the other hand, if the guard column 141 is longer than 4 m, the carrier gas flow rate must be greatly increased to achieve the same linear velocity as when the guard column is not used, resulting in a large increase in carrier gas consumption. . Therefore, the length of the guard column 141 is preferably 50 cm or more and 4 m or less.

FIG. 3 shows the relationship between the carrier gas flow rate and the length of the guard column required to achieve a linear velocity of 52.1 cm/sec using the same separation column with a length of 15 m and an inner diameter of 0.25 mm as in this example. . If the length of the guard column 141 is 4 m or less, the increase in the carrier gas flow rate can be suppressed to 30% or less of the flow rate when the guard column 141 is not used. If the guard column 141 with a length of 2 m is used as in the present embodiment, the linear velocity can be the same as when the guard column 141 is not used, simply by increasing the flow rate of the carrier gas by 10%. The flow rate of the carrier gas itself depends on the inner diameter of the column and the length of the separation column, but in many cases, the relationship between the flow rate of the carrier gas and the length of the guard column is similar to that shown in FIG. Therefore, it is preferable to set the length of the guard column to 50 cm or more and 4 m or less.

The mass spectrometer 20 includes an electron ionization source 22 , an ion lens 23 , a quadrupole mass filter 24 and an ion detector 25 inside a vacuum chamber 21 . Sample components temporally separated inside the column 14 are sequentially introduced into the electron ionization source 22 and ionized by irradiation with thermal electrons emitted from a filament (not shown).

The control/processing unit 30 has a storage unit 31 . The storage unit 31 stores method files used when measuring the controlled compounds. A method file is a file that describes measurement conditions for a regulated compound. The measurement conditions include the temperature of the pyrolyzer 12, the temperature of the separation column 142 (the temperature of the column oven 15), the type and flow rate of the carrier gas, and the phthalates, PBBs, and PBDEs, which are regulated compounds. It contains information such as two types of ions (a quantifying ion and a confirming ion). FIG. 4 shows an example of measurement conditions. Figure 4 shows three ions for phthalates (one quantifying ion and two confirming ions) and two ions for PBBs and PBDEs (one quantifying ion and one confirming ion). ) is described. A quantifying ion is used to quantify the compound from the area (or height) of the peak of the quantifying ion. The confirmation ion is used to confirm (identify) the compound based on the fact that the ratio of the height of the peak area of the quantitation ion and the height of the peak area of the confirmation ion is within a preset range. Depending on the sample to be measured, the mass-to-charge ratio of one of these quantification ions and confirmation ions is close to the mass-to-charge ratio of ions generated from contaminants contained in the sample, and ions with this mass-to-charge ratio should be used. may not be possible. Therefore, the storage unit 31 also stores information on the mass-to-charge ratio of one or more preliminary ions for each compound.

In addition, the storage unit 31 stores a relative response coefficient database 311 . The relative response factor database 311 associates one or more predetermined reference compounds included in the regulated compounds with reference compounds that are regulated compounds other than the reference compounds. In the relative response sensitivity factor database 311, the ratio of the detection sensitivity of the reference compound to the detection sensitivity of the reference compound (relative response factor RRF) is stored in a database. An example of a relative response factor table for PBBs and PBDEs is shown in FIG. Similarly, a relative response coefficient database (for example, Non-Patent Document 4) is stored for phthalates. The relative response factor database 311 is used when performing "2-1. Screening of regulated compounds using the relative response factor database" (described later), and "2-2. When "screening of regulated compounds" (described later) is performed, it is not necessary to store the relative response coefficient database 311 in the storage unit 31. FIG.

The relative response factor RRF _a/x of the reference compound a with respect to the standard compound x is represented by the following formula (1).
RRFa _/x = _RFa / _RFx ...(1)
where RFa and RFx are the response factors for reference compound a and reference compound x, respectively.

The response factor RF _a of reference compound a is represented by the following formula (2). Note that the following formulas apply not only to the reference compound a but also to the standard compound x.
RF _a =A _a /m _a …(2)
where A _a and ma are the peak area and weight (mg) of reference compound _a in the mass chromatogram, respectively. Also, the weight ma of the reference compound _a is represented by the following formula (3).
m _a = M × C _a … (3)
Here, M and C _a are the weight (kg) of the standard sample and the concentration (mg/kg) of the reference compound a contained in the standard sample, respectively.

The control/processing unit 30 includes, as functional blocks, a reference compound determination unit 32, a standard sample measurement unit 33, an analysis target sample measurement unit 34, a reference compound quantification unit 35, a reference compound quantification unit 36, and a screening unit 37. . The entity of the control/processing unit 30 is a general personal computer, and each functional block described above is realized by executing a preinstalled analysis sample measurement program on the processor. The control/processing unit 30 is also connected to an input unit 4 for a user to perform an input operation and a display unit 5 for displaying various information. Of the above functional blocks, the reference compound determination unit 32 and the reference compound quantification unit 36 (the functional blocks indicated by the dashed lines in FIG. 1) perform “2-1. Screening of regulated compounds using relative response factor database” (described later). When performing "2-2. Screening of regulated compounds using the calibration curve of each regulated compound" (described later), the control/processing unit 30 controls the standard sample measurement unit 33, the analysis target A sample measurement unit 34, a reference compound quantification unit (quantification unit) 35, and a screening unit 37 (functional blocks indicated by solid lines in FIG. 1) may be provided.

2. Screening Procedure for Regulated Compounds Next, a procedure for screening a sample to be analyzed will be described. The Py-GC-MS1 of this embodiment can perform two types of screening, ie, screening of controlled compounds using a relative response coefficient database and screening of controlled compounds using a calibration curve for each controlled compound.

2-1. Screening of Regulated Compounds Using the Relative Response Factor Database A procedure for screening regulated compounds using the relative response factor database will now be described with reference to the flow chart shown in FIG.

When the user instructs screening of regulated compounds, the reference compound determination unit 32 reads the relative response coefficient database 311 from the storage unit 31 and displays the relative response coefficient table (FIG. 5) described therein on the display unit 5. do. The user confirms this and changes the correspondence between the standard compound and the reference compound if necessary. For example, if it is difficult to obtain a standard sample containing the reference compound selected in the relative response coefficient table, the compound may be deleted from the reference compound, or another compound may be set as the reference compound. can be done. Once the user has confirmed the reference compound, the reference compound is determined (step 1).

Next, prepare a resin sample containing a known amount of each reference compound as a standard sample, set the container containing the standard sample in the pyrolyzer, and instruct the start of measurement.

When the measurement start is instructed, the standard sample measurement unit 33 performs measurement conditions described in the method file associated with the relative response coefficient database 311 stored in the storage unit 31 (related to measurement of the reference compound). (Step 2). In this embodiment, the temperature of the pyrolyzer 12 is first raised from 200° C. at a rate of 20° C./min based on the measurement conditions shown in FIG. After reaching 300° C., the temperature is raised at a rate of 5° C./min, and when the temperature reaches 340° C., the temperature is maintained for 1 minute. As a result, the controlled compound contained in the standard sample is vaporized (step 21). The vaporized controlled compound is introduced into the analysis column 14 along with the carrier gas flow. When the heating of the standard sample by the pyrolyzer 12 is completed, the standard sample measurement unit 33 displays the completion of heating on the display unit 5 (or notifies by voice or the like) and instructs the user to take out the container.

While heating the pyrolyzer 12, the sample injection part of the sample vaporization chamber 11 of the gas chromatograph is maintained at 300°C, and the analysis column 14 is maintained at 80°C (step 22). Therefore, each substance including the decomposed resin vaporized from the standard sample by the pyrolyzer 12 is introduced into the analysis column 14 while being gradually cooled (step 23). Decomposed resin introduced into the analysis column 14 adheres to the inner wall inside the guard column 141 provided on the inlet side of the analysis column 14 . The regulated compound adheres to the inner wall of the guard column 141 or mainly reaches the inlet of the separation column 142 and adheres.

When the user takes out the container from the pyrolyzer 12 , the standard sample measuring section 33 starts heating the column oven 15 . In this example, the temperature was raised from 80° C. at a rate of 20° C./min and maintained at 320° C. for 4 minutes. The regulated compounds adhering to the inlet of the separation column 142 enter the separation column 142 in order from those that have reached the vaporization temperature of each compound, and are transferred to the stationary phase 1421 by the action of the stationary phase 1421 of the separation column 142. It advances through the separation column 142 while desorbing and flows out. Compounds exiting the separation column 142 are in turn introduced into the electron ionization source 22 .

The ions generated by the electron ionization source 22 are converged near the central axis (ion optical axis C) in the direction of flight by the ion lens 23, and then enter the quadrupole mass filter 24. It is separated and detected by the ion detector 25 (step 24). Output signals from the ion detector 25 are sequentially transmitted to and stored in the storage unit 31 .

During the measurement of the standard sample, the mass spectrometry unit 20 repeatedly performs scan measurement and selective ion monitoring (SIM) measurement. Specifically, the mass-to-charge ratio of ions passing through the quadrupole mass filter 24 is scanned in a predetermined range (for example, the range of m/z is 50 to 1000), and A preset SIM measurement for each m/z in which the mass-to-charge ratio of the ion to be measured is fixed to the mass-to-charge ratio of the quantitation ion or confirming ion of each compound for a predetermined time is set as one set, and this is repeated. Note that the scan measurement is not essential, and only the SIM measurement may be repeatedly performed.

In addition to measuring standard samples, n-alkane samples are also measured. An n-alkane sample is a standard sample containing multiple compounds with different hydrocarbon chain lengths, and is used to obtain a retention index based on the retention time of each compound. As described in Non-Patent Document 4, the retention index Ix of compound x is represented by the following formula (4).
_Ix= 100(Cn _+i -Cn){( _tx -tn)/( _tn _+i - _tn ) _} + _100Cn ...(4)
Here, C _n , C _n+i are the numbers of carbon atoms in n-alkanes positioned before and after the retention time of the compound, t _x is the retention time of compound x, t _n , t _n+i are the retention times of the n-alkanes before and after the retention time of the compound. If the retention index of each regulated compound is obtained in advance, the measurement of the n-alkane sample is omitted here, and the n-alkane sample is measured only when the sample to be analyzed is measured. The retention time of each regulated compound may be estimated from the retention time of each compound contained in the sample and the previously obtained retention index value of the regulated compound.

Upon completion of the measurement of the standard sample, the standard sample measuring section 33 creates a calibration curve corresponding to each reference compound (step 3). Here, only one standard sample is measured to create a one-point calibration curve. When the amount of the reference compound and the measured intensity are in a non-linear relationship, a plurality of standard samples with different contents of the reference compound may be measured to create a calibration curve based on two or more measurement points.

After creating the calibration curve of the reference compound, the user sets the sample to be analyzed and instructs the start of measurement. The sample to be analyzed is measured using the measurement conditions obtained (step 4). Specifically, based on the measurement conditions shown in FIG. 3, the pyrolyzer 12 is first heated from 200° C. at a rate of 20° C./min. After reaching 300° C., the temperature is raised at a rate of 5° C./min, and when the temperature reaches 340° C., the temperature is maintained for 1 minute. As a result, the controlled compound contained in the standard sample is vaporized (step 41). The vaporized controlled compound is introduced into the analysis column 14 along with the carrier gas flow. When the heating of the standard sample by the pyrolyzer 12 is completed, the standard sample measurement unit 33 displays the completion of heating on the display unit 5 (or notifies by voice or the like) and instructs the user to take out the container.

While heating the pyrolyzer 12, the sample injection part of the sample vaporization chamber 11 of the gas chromatograph is maintained at 300°C, and the analytical column 14 is maintained at 80°C (step 42). Therefore, each substance including the decomposed resin vaporized from the sample to be analyzed by the pyrolyzer 12 is introduced into the analysis column 14 while being gradually cooled (step 43). Decomposed resin products introduced into the analysis column 14 adhere to the inner wall of the guard column 141 provided on the inlet side of the analysis column 14 . The regulated compound adheres to the inner wall of the guard column 141 or mainly reaches the inlet of the separation column 142 and adheres.

When the user takes out the container from the pyrolyzer 12 , the standard sample measuring section 33 starts heating the column oven 15 . In this example, the temperature was raised from 80° C. at a rate of 20° C./min and maintained at 320° C. for 4 minutes. The regulated compounds adhering to the inlet of the guard column 141 or the separation column 142 enter the separation column 142 in order from those that have reached the vaporization temperature of each compound, and interact with the stationary phase 1421 of the separation column 142. It advances through the separation column 142 while desorbing to the stationary phase 1421 and flows out. The compounds discharged from the separation column 142 are sequentially mass-separated by the mass spectrometer 20 and detected by the ion detector 25 (step 44).

In addition, when predicting the retention time of each target compound based on the retention index, an n-alkane sample may also be measured separately from the measurement of the sample to be analyzed. In the measurement of the sample to be analyzed, scan measurement is not essential, and only SIM measurement may be performed. However, by performing scan measurement, if a large peak other than the compound to be measured is found after creating the total ion current chromatogram, by analyzing the mass spectrum obtained at the retention time of the peak, Compounds corresponding to peaks can be identified.

When the measurement of the sample to be analyzed is completed, the reference compound quantification unit 35 generates quantitative ions and confirmation ions based on the respective retention indices of the reference compounds, or the predicted retention times calculated based on the retention indices and the measurement data of n-alkanes. Determine the mass chromatogram peak of . Then, it is confirmed that the peak area of the quantitative ion and the peak area of the confirmation ion are within a predetermined range, and the quantitative value is obtained by comparing the peak area of the quantitative ion with the calibration curve of the reference compound (step 5). .

When the quantitative value of the reference compound is obtained, the reference compound quantification unit 36 calculates the retention time of each reference compound, or the predicted retention time calculated based on the retention index of each reference compound and the measurement data of n-alkane, Determine the mass chromatogram peaks of the quantitation and confirming ions for each reference compound. Then, it is confirmed that the peak area of the quantitative ions and the peak area of the confirmation ions are within a predetermined range. In addition, quantitation of each reference compound based on the amount of the reference compound contained in the standard sample, the peak area of the quantification ion of the reference compound detected by measuring the standard sample, the peak area of the quantification ion of the reference compound and the relative response factor Obtain a value (step 6).

When quantitative values are obtained for the standard compound and the reference compound, the screening unit 37 compares these quantitative values with predetermined threshold values to screen the sample to be analyzed. In this example, based on the standard values in the RoHS Directive (the amount of DEHP, the amount of BBP, the amount of DBP, the amount of DIBP, the total amount of PBBs, and the total amount of PBDEs are all 1000 mg / kg or less), the analysis target Screening judgment whether the quantitative values of DEHP, BBP, DBP, and DIBP contained in the sample are within the range of ±50% of the reference value, and whether the total amount of PBBs and PBDEs is within the range of ±70% of the reference value. (step 7).

Specifically, for example, the following criteria described in Non-Patent Document 5 can be used. If the quantitative value of DEHP, BBP, DBP, and DIBP contained in the sample to be analyzed is 500 mg/kg or less, and if the total quantitative value of PBBs and PBDEs is all 300 mg/kg or less, the analysis Judge that the target sample satisfies the standards of the RoHS Directive. In addition, if the quantitative values of DEHP, BBP, DBP, and DIBP are 1500mg/kg or more, or if any of the total quantitative values of PBBs and PBDEs is 1700mg/kg or more, the sample to be analyzed shall comply with the RoHS Directive. judged not to meet the criteria. And when the quantitative values of DEHP, BBP, DBP, and DIBP are 300 mg/kg to 1500 mg/kg (excluding cases where any of them is 1500 mg/kg or more), either of the total values of the quantitative values of PBBs and PBDEs If it is within the range of 300 mg/kg to 1700 mg/kg (excluding the case where any of them is 1700 mg/kg or more), the judgment will be suspended, and the sample to be analyzed will be analyzed in detail by another method and quantified more strictly. Calculate the value.

2-2. Screening of Regulated Compounds Using Calibration Curves of Each Regulated Compound A procedure for screening a regulated compound using a calibration curve of each regulated compound will be described with reference to the flowchart shown in FIG. The description of the same procedure as the screening of controlled compounds using the relative response factor database will be omitted as appropriate.

When the user sets a container containing a standard sample, which is a resin sample containing known amounts of all regulated compounds, to the pyrolyzer and instructs the start of measurement, the standard sample measurement unit 33 is stored in the storage unit 31. The standard sample is measured according to the measurement conditions described in the method file (step 11). The procedure (steps 21 to 24) for the measurement of the standard sample is the same as in the case of using the relative response factor database (except that all controlled compounds are measured), so a detailed explanation is omitted.

After completing the measurement of the standard sample, the standard sample measurement unit 33 creates a calibration curve for each regulated compound (step 12). Again, measure only one standard sample to create a one-point calibration curve. If there is a non-linear relationship between the amount of a regulated compound and the measured intensity, multiple standard samples with different contents of the regulated compound may be measured, and a calibration curve based on two or more measurement points may be created.

After creating the calibration curve for each regulated compound, the user sets the sample to be analyzed and instructs the start of measurement. The sample to be analyzed is measured using the measurement conditions described in the method file (step 13). The procedure (steps 41 to 44) for measurement of the sample to be analyzed is also the same as in the case of using the relative response coefficient database, so detailed description will be omitted.

When the measurement of the sample to be analyzed is completed, the reference compound quantification unit 35 determines the mass chromatogram peaks of the quantitative ions and confirmation ions of each regulated compound based on the retention time of each regulated compound obtained during the measurement of the standard sample. to decide. Then, it is confirmed that the peak area of the quantitative ion and the peak area of the confirmation ion are within a predetermined range, and the quantitative value is obtained by comparing the peak area of the quantitative ion with the calibration curve of each regulatory compound (step 14). .

When quantitative values are obtained for each regulated compound, the screening unit 37 compares these quantitative values with predetermined threshold values to screen the sample to be analyzed. Here, same as above, analysis based on the standard values in the RoHS Directive (the amount of DEHP, the amount of BBP, the amount of DBP, the amount of DIBP, the total amount of PBBs, and the total amount of PBDEs are all 1000 mg/kg or less). Screening whether the quantified values of DEHP, BBP, DBP, and DIBP contained in the target sample are within ±50% of the standard value, and whether the total amount of PBBs and PBDEs are within ±70% of the standard value. Determine (step 15).

Thus, in this embodiment, the separation column 142 provided with the stationary phase for separating the controlled compound and the guard column 141 provided integrally with the separation column 142 on the inlet side of the separation column 142 are used. A column 14 having Since the separation column 142 and the guard column 141 are integrally constructed without using connecting parts, the work of connecting them using members such as nuts and ferrules is required as in the case of using conventional general guard columns. no need to do In addition, the carrier gas and the regulated compound do not leak from the connection between the two, and the regulated compound does not adsorb and decompose when the connecting member is touched. Therefore, deterioration of the separation column 142 can be suppressed without requiring complicated work, and regulated compounds that tend to adhere to the separation column 142 or decompose can be measured correctly.

The results of an experiment to confirm the effect of preventing contamination of the separation column 142 by using the measurement method and column 14 of the above example will be explained. In this experiment, a resin standard sample for measuring phthalates containing 100 mg/kg DBP (manufactured by Shimadzu Corporation, P/N: 225-31003-91) was repeatedly measured, and the mass chromatogram obtained for each measurement was Gram's peak shape (symmetry) was confirmed. The peak shape is represented by an index called a symmetry coefficient, and the greater the tailing of the peak, the greater the value of the symmetry coefficient. Normally, when the symmetry coefficient exceeds 2.5, it is determined that the column is contaminated, and the column is replaced.

FIG. 8 shows the results of measurement using the column 14 of the above example (measurement conditions are the same as in the above example in FIG. 4). The graph in FIG. 8 plots changes in the symmetry coefficient with respect to the number of measurements. A column without a guard column usually had a symmetry coefficient of more than 2.5 after 300-400 measurements. . In other words, conventionally, it was necessary to replace the column every time 300 to 400 measurements were performed. It can be seen that the durability of the column 14 is more than doubled without the need for any work.

The above embodiment is just an example, and can be modified as appropriate in line with the spirit of the present invention. In the above example, Py-GC-MS1 was used to thermally desorb the controlled compound by the Py/TD-GC/MS method to screen the sample for analysis. It is also possible to screen the sample to be analyzed by The apparatus configuration for the Py-GC/MS method is the same as in the above examples, and the sample heating temperature by the pyrolyzer is different. Moreover, it is also possible to employ a configuration in which a controlled compound is vaporized from a sample using a thermal desorption device that does not use a pyrolyzer. In any of these, the maximum temperature at which the resin sample is heated in order to vaporize the target compound contained in the resin sample is higher than the heating temperature of the separation column. Since other substances (decomposition products of the resin and contaminant compounds) are introduced into the analysis column 14, contamination of the separation column 142 can be prevented by providing the guard column 141 as in the above embodiment. In addition, since the guard column 141 and the separation column 142 are integrally configured without connecting fittings such as nuts and ferrules, compounds that easily adsorb and decompose, such as phthalates and flame-retardant brominated compounds, are not used. can be measured correctly.

Also, in the above example, each compound flowing out from the column 14 was configured to be subjected to mass spectrometry, but each compound can also be detected by a method other than mass spectrometry. Such detectors include, for example, flame ionization detectors (FID), thermal ionization detectors (FTD), flame photometric detectors (FPD), electron capture detectors (ECD), sulfur chemiluminescence detectors (SCD). , thermal conductivity detector (TCD), barrier discharge ionization detector (BID), etc. can also be used.

[Aspect]
It will be appreciated by those skilled in the art that the multiple exemplary embodiments described above are specific examples of the following aspects.

(Section 1)
A method for measuring a phthalate ester and a brominated flame retardant compound according to one aspect of the present invention comprises:
heating a sample containing a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group to vaporize the target compound contained in the sample;
An analysis column having a separation column internally provided with a stationary phase for separating the target compound, and a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts. , adjusting the temperature to a temperature lower than the maximum temperature at which the target compound is vaporized,
introducing the vaporized target compound into the analysis column;
A target compound flowing out from the separation column is detected.

(Section 8)
Another aspect of the present invention is a gas chromatograph column used in carrying out a method for measuring phthalates and brominated flame retardant compounds,
a separation column provided with a stationary phase for separating a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group;
and a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts.

The gas chromatograph column described in Section 8 is used in the method for measuring phthalates and brominated flame retardant compounds in Section 1. In this gas chromatograph column, the separation column and the guard column are integrally constructed without using connecting parts, so there is no need to connect them. Also, the target compound is not adsorbed and decomposed. Therefore, deterioration of the separation column can be suppressed without requiring complicated work, and phthalate esters and brominated flame-retardant compounds, which tend to adhere to the separation column or decompose, can be measured correctly.

(Section 2)
In the method for measuring phthalates and brominated flame retardants according to item 1,
The target compound is vaporized in the pyrolyzer.

In the method for measuring phthalates and brominated flame retardant compounds in Section 2, by appropriately setting the temperature at which the sample is heated in the pyrolyzer, the target compound is vaporized by thermal decomposition and the target by thermal desorption. The method of vaporizing the compound can be properly used.

(Section 3)
In the method for measuring the phthalates and brominated flame retardant compounds according to

item

1 or 2,
Of the analysis columns, only the separation column is provided with a stationary phase.

Some conventionally used guard columns have a stationary phase (liquid phase) inside. By providing the stationary phase inside the guard column, contaminants are more likely to be collected and less likely to reach the separation column, so that the separation column is less likely to be contaminated. On the other hand, however, contaminants trapped in the stationary phase of the guard column flow out, and the peak tends to tail when the target compound is measured. In the method for measuring phthalates and brominated flame retardants in Section 3, an analysis column in which a stationary phase is provided only in the separation column is used. Content can be measured accurately.

(Section 4)
In the method for measuring phthalates and brominated flame retardant compounds according to any one of items 1 to 3,
The guard column has a length of 50 cm or more and 4 m or less.

In the method for measuring phthalates and brominated flame retardants in Section 4, the use of a guard column with a length of 50 cm or longer causes contaminants such as resin decomposition products to enter the separation column and contaminate the separation column. can be prevented. In addition, since the guard column is 4 m or shorter, the target compound can be measured at the same linear velocity by increasing the flow rate of the carrier gas by about 30% compared to when the guard column is not used.

(Section 5)
In the method for measuring phthalates and brominated flame retardant compounds according to any one of items 1 to 4,
The separation column has a length of 10 m or more and 30 m or less.

In the measurement method for phthalates and brominated flame-retardant compounds in Section 5, the controlled compounds contained in the sample can be sufficiently separated by using a separation column with a length of 10m or longer. Moreover, since the length of the separation column is 30 m or less, the measurement time does not become extremely long.

(Section 6)
In the method for measuring phthalates and brominated flame retardant compounds according to any one of items 1 to 5,
The target compound flowing out from the separation column is detected by mass separation.

Resin samples containing phthalates and brominated flame retardant compounds contain various contaminants other than the target compound. In addition, decomposition products of the resin also enter the column of the gas chromatograph when the target compound is vaporized. In the measurement method for phthalates and brominated flame-retardant compounds in Section 6, each compound that has flowed out from the separation column is detected by mass separation, so even if contaminants co-eluted with the target compound are present, Contaminants can be found with high accuracy and the content of target compounds can be measured correctly.

(Section 7)
In the method for measuring phthalates and brominated flame retardant compounds according to any one of items 1 to 6,
The sample is screened based on whether the content of the target compound is within a predetermined range.

The method for measuring the phthalate esters and brominated flame retardant compounds described in items 1 to 6 is as described in item 7. Whether the content of the target compound is within a predetermined range or not It can be suitably used for screening the sample based on the above. In particular, by using an analysis column having a guard column and a separation column having lengths as described in the fourth and fifth items, the sample to be analyzed can be screened with high efficiency.

DESCRIPTION OF SYMBOLS 1... Thermal desorption-gas chromatography/mass spectrometer 10... Gas chromatograph part 11... Sample vaporization chamber 12... Pyrolyzer 13... Carrier gas flow path 14... Column (analysis column)
141... Guard column 142... Separation column 1421... Stationary phase 15... Column oven 20... Mass spectrometer 21... Vacuum chamber 22... Electron ionization source 23... Ion lens 24... Quadrupole mass filter 25... Ion detector 30... Control/ Processing unit 31 Storage unit 311 Relative response coefficient database 32 Reference compound determination unit 33 Standard sample measurement unit 34 Analysis sample measurement unit 35 Reference compound quantification unit 36 Reference compound quantification unit 37 Screening unit 4 Input Part 5... Display part

Claims

heating a sample containing a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group to vaporize the target compound contained in the sample;
An analysis column having a separation column internally provided with a stationary phase for separating the target compound, and a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts. , adjusting the temperature to a temperature lower than the maximum temperature at which the target compound is vaporized,
introducing the vaporized target compound into the analysis column;
A method for measuring phthalate esters and brominated flame-retardant compounds, wherein the target compound flowing out from the separation column is detected.
The method for measuring phthalate esters and brominated flame retardant compounds according to claim 1, wherein the target compound is vaporized in a pyrolyzer.
The method for measuring phthalates and brominated flame-retardant compounds according to claim 1, wherein only the separation column of the analysis columns is provided with a stationary phase.
The method for measuring phthalates and brominated flame retardant compounds according to claim 1, wherein the guard column has a length of 50 cm or more and 4 m or less.
The method for measuring phthalates and brominated flame-retardant compounds according to claim 1, wherein the separation column has a length of 10 m or more and 30 m or less.
The method for measuring phthalates and brominated flame-retardant compounds according to claim 1, wherein the target compounds flowing out from the separation column are detected by mass separation.
Further, the method for measuring phthalate esters and brominated flame retardant compounds according to claim 1, wherein the sample is screened based on whether the content of the target compound is within a predetermined range.
a separation column provided with a stationary phase for separating a target compound belonging to at least one of the phthalates, the polybrominated biphenyl group, and the polybrominated diphenyl ether group;
A gas chromatograph column comprising: a guard column provided integrally with the separation column on the inlet side of the separation column without using connecting parts.