WO2005001465A1

WO2005001465A1 - Chemical substance detector and method of detecting chemical substance

Info

Publication number: WO2005001465A1
Application number: PCT/JP2003/008237
Authority: WO
Inventors: Hideo Yamakoshi; Hiroshi Futami; Minoru Danno; Shigenori Tsuruga; Shizuma Kuribayashi
Original assignee: Mitsubishi Heavy Industries, Ltd.
Priority date: 2003-06-27
Filing date: 2003-06-27
Publication date: 2005-01-06
Also published as: CN1623088A; CN100458435C; DE10393404T5

Abstract

Chemical substance detector (100) comprising vacuum ultraviolet lamp (3) whereby a chemical substance to be detected contained in exhaust gas (Gs) is ionized. The ionized chemical substance to be detected is confined in ion trapping unit (10) adapted to generate high-frequency electric field thereinside. The ion group present in the ion trapping unit (10) is energized by SWIFT waveforms containing frequency components excluding the frequency corresponding to the orbit resonance frequency of the ion of chemical substance to be detected to thereby remove impurities. Subsequently, the above ion group is energized by TICKLE waveform having the frequency component corresponding to the orbit resonance frequency of the ion of chemical substance to be detected to thereby fragment the ion of chemical substance to be detected. The masses of resultant fragments are measured by means of mass spectrometer (4), thereby attaining identification of the chemical substance to be detected.

Description

Chemical substance detection device and chemical substance detection method

Technical field

The present invention relates to an apparatus for detecting a chemical substance and a method for measuring the concentration of a chemical substance.

The present invention relates to a chemical substance detection device and a chemical substance detection method for detecting with high accuracy.

Background art

In recent years, in order to reduce dioxins contained in exhaust gas discharged from refuse incineration facilities, attempts have been made to measure dioxins or their precursors contained in exhaust gas in real time and use them for combustion control in incinerators. Has begun. For the measurement of dioxins, a high-resolution G CZMS (Gas Chromatography Z-Mass Spectrometer) measurement method is known. It currently takes several weeks. Therefore, it is extremely difficult to apply to real-time control as described above. To solve this problem, an online monitor has been disclosed that ionizes dioxins and their precursors contained in exhaust gas by atmospheric pressure chemical ionization and measures these ions with a three-dimensional quadrupole mass spectrometer. . The details of this online monitor are described in the 1st Annual Meeting of the Society of Waste Management Research, 2000, so please refer to it if necessary.

By the way, the above-mentioned atmospheric pressure chemical ionization method has the following problems. First, due to its measurement principle, the sensitivity for measuring molecules that are unlikely to become negative ions is low, making it difficult to apply to precise control. Next, the ionization probability of the chemical substance to be measured is greatly affected by the atmosphere and gas composition. Therefore, the measured electrical signal strength In order to calculate the concentration from the force, it is necessary to use an expensive chemical substance containing a C isotope as an internal standard sample, so that the cost required for the measurement was high.

Next, in the above-mentioned atmospheric pressure chemical ionization method, it is generally assumed that there is a correlation with the concentration of dioxins and that phenols having relatively high measurement sensitivity are detected. However, phenols easily adhere to the piping, so they have a large memory effect, and cannot be measured with good sensitivity unless the piping is devised. Also, due to this memory effect, even if the exhaust gas becomes clean, phenols are detected and the measurement accuracy is reduced. Furthermore, if there is a substance in the exhaust gas that is more easily ionized than the precursor to be measured, it will be ionized first, making it difficult to accurately measure the substance to be measured. .

Also, even if a certain precursor (e.g., phenolic trichloride) is an optimal indicator of dioxins concentration in one furnace, other furnaces may have different furnace types and combustion conditions. is there. For this reason, in other furnaces, the indicator substance in one furnace is not always optimal, and the versatility is low if only one precursor can be measured. That is, in order to enhance versatility, it is preferable that various types of chemical substances can be detected at the same time, if possible.

Therefore, the present invention improves the detection sensitivity of the chemical substance to be detected, and controls the combustion conditions even during the operation of an incinerator, a heating furnace, or another combustion furnace. It is an object of the present invention to provide a chemical substance detection apparatus and a chemical substance detection method that can achieve at least one of improving the detection speed of a chemical substance and reducing the cost of a detection facility. . Disclosure of the invention

The chemical substance detection device according to the present invention provides a chemical substance to be detected that has a large ionization potential and a smaller energy than the sum of the ionization potential and the dissociation energy of ions of the chemical substance to be detected. Ionization means for applying to the substance and ionizing the chemical substance to be detected, electric field, magnetic field and other means Ion trap means for confining the ion group containing ions of the chemical substance to be detected ionized by the ionization means according to the above, and a frequency excluding a frequency corresponding to the orbital resonance frequency of the ion of the chemical substance to be detected An impurity removing means for applying energy to the ion group by a SW IFT waveform including a component to remove impurities, and a mass analyzing means for measuring a mass of the chemical substance to be detected.

When the chemical substance to be detected is ionized, the chemical substance detection device is configured to calculate the ionization potential greater than the ionization potential of the chemical substance to be detected and the dissociation energy of the ions of the chemical substance to be detected. A small amount of energy is given to the target chemical. As a result, the chemical substance to be detected can be ionized without being destroyed, so that the ionization efficiency can be increased.

Furthermore, when removing impurities, only a SWIFT waveform is given, so that impurities can be removed quickly. In addition, in the ionization according to the present invention, since the energy required for the ionization is appropriately set, various molecules are not dissociated or ionized indiscriminately. Because of this, the generation of fragments is very small, and the amount of impurities to be removed in the process of removing impurities is extremely small. As a result, the SWIFT voltage can be kept low, so that the remaining detection target chemical substances need not be destroyed, and the detection sensitivity of the mass spectrometry means can be increased. In addition, there is no need to prepare a large power supply unnecessarily, and the manufacturing cost of the device can be reduced. Further, in the chemical substance detection device according to the present invention, the generation of extra fragment ions can be extremely reduced. As a result, it is possible to suppress a decrease in trap efficiency due to a large amount of extra ions in the ion trap. Here, it is preferable to use a time-of-flight measurement method as the mass analysis means, because the measurement time can be shortened. Further, as the ion trap means, a means for confining ions inside by an electric or magnetic field or other electromagnetic force can be used. An electric field, a magnetic field, etc., may be used alone, or a plurality of them may be used in combination as appropriate. Traps are known and are preferred because they are relatively easy to handle (and so on).

The substance to be detected in the present invention refers to, for example, a dioxin precursor or dioxin contained in exhaust gas from an incinerator or the like. In this case, the chemical substance detection device according to the present invention can detect a precursor having a high correlation with dioxins and estimate the concentration of dioxins contained in the exhaust gas. It is also possible to directly detect dioxins contained in exhaust gas and determine their concentrations. The latter can also be used to test precursor estimates. Here, dioxins include molecules generally called dioxins {furan} cobraner PCB. The precursors include, for example, benzenes such as benzene, dichlorobenzene, and monochlorobenzene, and phenols such as phenol.

In addition, SWIFT is a Stored Waveform Inverse Fourier Transform, and Shinoita describes in the literature 〃 Development of a Capillary High-performance Liquid Chromato graphy randem Mass Spectrometry System Using SWIFT Technology in an Ion Trap / Reflectron Time-of-flight Mass Spectrometer Rapid Communication in mass spectrometry, vol. 11 1739-1748 (1997).

The chemical substance detection device according to the next invention detects the energy larger than the ionization potential of the chemical substance to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ion of the chemical substance to be detected. In addition to the target chemical substance, ionization means for ionizing the substance to be detected and an ion group containing ion of the chemical substance to be detected ionized by the ionization means by an electric field, a magnetic field or other means are confined. Ion trap means; impurity removing means for applying energy to the ion group by a SWIFT waveform including a frequency component excluding a frequency corresponding to the orbital resonance frequency of the ion of the detection target chemical substance to remove impurities, In the TICKLE waveform of the frequency component corresponding to the orbital resonance frequency of the ion of the target chemical substance, the ion Energy is given to the group to detect ions of the target substance. Fragmentation means for fragmentation; and mass analysis means for measuring the mass of the fragment of the chemical substance to be detected.

In this chemical substance detection device, the chemical substance to be detected is fragmented by fragmentation means that gives a TICKLE waveform, so even if there is an impurity in the mass number of the chemical substance to be detected, this effect can be eliminated and accurate measurement can be performed . In addition, since the number of fragments generated during ionization is extremely small, the target chemical substance to be detected can be efficiently fragmented when the chemical substance to be detected is fragmented. As a result, almost all of the fragments of the substance to be detected can be measured by the mass spectrometry means, so that the detection sensitivity of the mass spectrometry means can be increased and more precise combustion control can be performed. Here, TICKLE is an operation of fragmenting the chemical substance to be detected and separating the chemical substance to be detected from the impurities whose mass number is similar to that of the chemical substance to be detected. Capillary high—performance Liquid Chromatography Tandem Mass Spectrometry System Using SWIFT Technology in an Ion Trap / Reflectron Time-of-flight Mass Spectrum Meter.

The apparatus for detecting a chemical substance according to the next invention is the apparatus for detecting a chemical substance, wherein the ionization means outputs an energy higher than an ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential. It is characterized by being given to substances. Further, the chemical substance detection device according to the next invention is the chemical substance detection device, wherein the ionization means is a light generation means for generating light having a wavelength of 50 nm or more and 200 nm or less. Features. Further, in the chemical substance detection device according to the next invention, in the chemical substance detection device, the ionization means is a vacuum ultraviolet light lamp.

In the case where energy is applied to the substance to be detected by the ionization means as in these inventions, the energy is preferably higher than the ionization potential and equal to or less than the value obtained by adding 4 eV to the ionization potential. When the chemical substance to be detected is ionized by the energy of light, the wavelength should be 50 nm or more and 200 n m or less is desirable. It is preferable to use a vacuum ultraviolet lamp because such light can be easily obtained.

An apparatus for detecting a chemical substance according to the next invention comprises an ion trap means for confining an ion group including an ion of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means; and a signal intensity higher than a predetermined signal intensity. At a frequency corresponding to the orbital resonance frequency of the impurity present at a concentration that indicates a voltage greater than the voltage amplitude in the frequency band corresponding to the orbital resonance frequency of the impurity existing at a concentration that indicates a signal intensity lower than the predetermined signal intensity Arbitrary waveform generating means for generating a SW IFT waveform having an amplitude; and applying the SW IFT waveform generated by the arbitrary waveform generating means to a group of ions confined in the ion trap means to remove the impurities. Mass spectrometry means for measuring the mass of the target chemical substance or its fragment. Sign.

According to the present invention, the voltage amplitude of the SW IFT waveform at a frequency corresponding to the mass number of an impurity present at a concentration higher than a specific signal intensity is increased, and the voltage amplitude at a frequency corresponding to the mass number at a low impurity concentration is increased. By lowering the concentration, highly concentrated impurities can be selectively removed. As a result, impurities can be selectively removed, and the energy required for SWIFT can be reduced. In addition, since the power supply unit can be made compact, it is economical because it is not necessary to use a large power supply without necessity. Here, the impurity that increases the voltage amplitude of the SW IFT waveform is preferably an impurity that exists at a concentration that exhibits a signal intensity at least as high as the signal intensity of the chemical substance to be detected. Although impurities with even lower mass numbers may be targeted, the energy required for SW IFT increases, so it is preferable to target impurities with a signal intensity of 50% or more of the signal intensity of the target chemical substance. .

The chemical substance detection device according to the next invention comprises: an ion trap means for confining an ion group including an ion of the chemical substance to be detected ionized by an electric field, a magnetic field or other means; and a voltage amplitude as the frequency increases. An arbitrary waveform generating means for generating a reduced SW IFT waveform; and Mass spectrometry means for measuring the mass of the chemical substance to be detected or a fragment thereof, after removing the impurities by giving the ions to the group of ions confined in the trapping means.

The chemical substance detection device according to the present invention is configured to give, to an impurity having a large mass number, energy equivalent to energy given to an impurity having a small mass number. Generally, the orbital resonance frequency in an ion trap is a function of the mass number, but as the mass number increases, the frequency decreases, and the frequency interval corresponding to the mass number interval 1 decreases. On the other hand, conventional literature Lleve 丄 opmeir of a Capillary High-performance Liquid Chromatography Tandem Mass Spectrometry System Using SWIFT Tech no logy in an Ion Trap / Reflectron Time-of -flight Mass Spectrometer Rapid Communication in mass spectrometry, vol. 11 1739-1748 In the SW IFT waveform generation generally performed in (1997) and the like, a SW IFT waveform is generated by converting a frequency spectrum having a constant voltage amplitude into a time domain by an inverse Fourier transform. In this case, a sum waveform having a constant voltage amplitude at a constant frequency interval is generated. Therefore, in this case, as the mass number is larger, the number of sine waves per mass number interval 1 is smaller, and the energy per mass number interval 1 is smaller. That is, the energy applied to a molecule having a large mass number becomes relatively small. On the other hand, in the present invention, since the voltage amplitude of the sine wave is increased and compensated by the decrease in the number of sine waves, sufficient energy can be given to ions having a large mass number. Such impurities can be more reliably removed. Also, energy can be given to ions having a small mass number in a necessary and sufficient range, so that the energy use efficiency can be increased. Furthermore, since a large power supply is not required, the installation cost of the equipment can be reduced.

The chemical substance detection device according to the next invention includes an ion trap means for confining an ion group including an ion of the chemical substance to be detected ionized by an electric field, a magnetic field, or the like, and a mass number of a molecule to be removed by SWIFT. An arbitrary waveform generator for generating a SWIFT waveform having a constant voltage amplitude regardless of the SWIFT waveform; Mass spectrometry means for measuring the mass of the chemical substance to be detected or a fragment thereof after applying the T waveform to the ion group confined in the ion trap means to remove the impurities. Features.

In this chemical substance detection device, when the frequency spectrum of the SWIFT waveform whose voltage amplitude is increased as the frequency decreases is converted to the mass number on the horizontal axis, the voltage amplitude per unit mass number is substantially constant. It is made to become. For this reason, substantially constant energy can be given to molecules of any mass to be removed by SWIFT. As a result, sufficient energy can be given to ions having a large mass number, so that such impurities can be more reliably removed. Also, energy can be given to ions having a small mass number in a necessary and sufficient range, so that the energy use efficiency can be increased. In addition, since a large power supply is not required, installation costs can be reduced.

An apparatus for detecting a chemical substance according to the next invention comprises an ion trap means for confining an ion group including an ion of the chemical substance to be detected ionized by an electric field, a magnetic field, or the like, and a mass number of the plurality of chemical substances to be detected. An arbitrary waveform generating means for generating a SW IFT waveform that does not apply a voltage amplitude in a plurality of frequency bands corresponding to the frequency band and gives a voltage amplitude in a frequency band corresponding to the mass number of the impurity; and Fragmentation means for energizing the ion group with a TICKLE waveform having a plurality of frequency components corresponding to the orbital resonance frequency of the elephant chemical to fragment the ions of the plurality of detection target substances, and the SWIFT After giving the waveform to the ions trapped in the ion trap means to remove the impurities, the detection target chemical substance Alternatively, a mass spectrometer for measuring the mass of the fragment is provided.

Since dioxins and their precursors contained in the exhaust gas from incinerators are extremely small, it is extremely important to improve their detection accuracy when controlling the incinerator combustion conditions in real time. The chemical substance detection device according to the present invention provides a SWIFT that does not apply a voltage amplitude in a frequency band corresponding to a plurality of detection target chemical substances. The impurities are removed using the waveform. Then, a plurality of chemical substances to be detected are simultaneously detected by the mass spectrometry means. As described above, since a plurality of chemical substances to be detected are simultaneously detected, highly accurate measurement can be performed, and combustion control accuracy can be increased.

The apparatus for detecting a chemical substance according to the next invention is the above-described apparatus for detecting a chemical substance, wherein the ionization potential of the chemical substance to be detected is larger than the ionization potential of the chemical substance to be detected, and It is characterized in that it comprises ionization means for applying an energy smaller than the sum of the dissociation energy to the chemical substance to be detected and ionizing the chemical substance to be detected. Further, the chemical substance detecting device according to the present invention is the chemical substance detecting device according to the above, wherein the ionizing means is higher than the ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential: ic Energy is given to the chemical substance to be detected.

The chemical substance detection apparatus according to these inventions provides the detection target chemical substance with high ionization potential and smaller energy than the dissociation energy to the detection target chemical substance to ionize the detection target chemical substance. . For this reason, unnecessary fragments are not generated, and the remaining detection target chemical substances do not need to be destroyed, so that the detection sensitivity of the mass spectrometry means can be increased. Therefore, in combination with the action and effect exerted by the above-mentioned chemical substance detection device, the detection sensitivity of the mass spectrometer can be further improved, and highly accurate measurement can be performed. And, in the combustion control of the incinerator, more precise control is possible. Further, since the SWIFT voltage can be kept low, there is no need to prepare a large power supply, and the manufacturing cost of the device can be further reduced.

The method for detecting a chemical substance according to the next invention is characterized in that an energy that is larger than the ionization potential of the chemical substance to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ion of the target substance. An ionization step of ionizing the detection target chemical substance to the detection target chemical substance; an ion trapping step of confining an ion group including ions of the detection target chemical substance ionized by an electric field, a magnetic field, or other means; The SWIFT waveform including a frequency component excluding the frequency corresponding to the orbital resonance frequency of the ions of the chemical substance to be detected An impurity removing step of applying energy to the group to remove impurities, and a mass spectrometric step of measuring the mass of the chemical substance to be detected.

In this method of detecting a chemical substance, when removing impurities, energy that is higher than the ionization potential of the chemical substance to be detected and smaller than the dissociation energy is given to the chemical substance to be detected. For this reason, impurities can be removed without removing the chemical substance to be detected, and when the impurities are removed, generation of unnecessary fragments is extremely small. Accordingly, the detection sensitivity of the mass spectrometry means can be increased because the remaining detection target chemical substance does not have to be destroyed. Furthermore, since only a SW IFT waveform is applied when removing impurities, impurities can be removed quickly. In addition, in the ionization according to the present invention, since the generation of fragments is very small, the amount of impurities to be removed in the process of removing impurities is extremely small. As a result, the SW IFT voltage can be kept low, so there is no need to prepare a large power supply, and the manufacturing cost of the device can be reduced. In the method for detecting a chemical substance according to the next invention, an energy that is larger than the ionization potential of the chemical substance to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ion of the chemical substance to be detected is detected. An ionization step of ionizing the object to be detected, the ion to be detected, and confining an ion group including ion of the ionized chemical to be detected by an electric field, a magnetic field or other means. A trapping step, an impurity removing step of applying energy to the ion group by a SW IFT waveform including a frequency component excluding a frequency corresponding to an orbital resonance frequency of ions of the detection target chemical substance to remove impurities, The energy is applied to the ion group with the TICKLE waveform of the frequency component corresponding to the orbital resonance frequency of the ion of the substance. And having a fragment of step fragmenting Ion detection object chemical substances giving ghee, and a mass analyzing step of measuring the mass of a fragment of the detection target chemical substance.

In this method for detecting a chemical substance, since the TICKLE waveform is given to the target chemical substance to fragment the chemical substance to be detected, impurities are not present in the frequency band corresponding to the mass number of the target chemical substance. However, accurate measurements can be made without this effect. Also, Since very few fragments are generated during ionization, the target chemical substance to be detected can be efficiently fragmented when the chemical substance to be detected is fragmented. As a result, almost all fragments of the chemical substance to be detected can be subjected to mass spectrometry, so that the detection sensitivity of the analysis can be increased in the mass spectrometry process. According to this detection method, more precise combustion control can be performed when controlling the combustion conditions of the incinerator.

A method for detecting a chemical substance according to the next invention comprises: an ion trapping step of confining an ion group containing ion of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means; and a distribution of impurities contained in the ion group. An impurity removal step of applying a SWIFT waveform including a frequency component corresponding to impurities present at a predetermined ratio or more to the ion group to remove impurities, and measuring the mass of the chemical substance to be detected or this fragment. And a mass spectrometry step.

In this method of detecting a chemical substance, impurities present at a predetermined ratio or more are selectively removed. For this reason, necessary and sufficient impurities can be removed with less energy than in the case of removing all impurities. For this reason, the power supply unit can be made smaller and economical. Here, it is preferable that the predetermined ratio targets impurities present at least as high as the signal intensity of the chemical substance to be measured. Although impurities having a smaller signal intensity may be targeted, the energy required for SWIFT is increased, so that impurities having a signal intensity of 50% or more of the signal intensity of the chemical substance to be measured are preferably targeted.

The method for detecting a chemical substance according to the next invention includes an ion trapping step of confining an ion group including ions of the chemical substance to be detected by an electric field, a magnetic field, or other means, and a signal intensity higher than a predetermined signal intensity. At a frequency corresponding to the orbital resonance frequency of the impurity present at the indicated concentration, the voltage amplitude is larger than the voltage amplitude in the frequency band corresponding to the orbital resonance frequency of the impurity present at a concentration indicating a signal intensity lower than the predetermined signal intensity. An impurity removing step of applying a SW IFT waveform having the following to the ion group to remove impurities; Mass spectrometry step of measuring the mass of the component.

In the method for detecting a chemical substance according to the present invention, the voltage amplitude of the SWIFT waveform having a frequency corresponding to an impurity present at a concentration indicating a signal intensity higher than a predetermined signal intensity is increased, and the frequency of a portion having a low impurity concentration is increased. The voltage amplitude is reduced. Therefore, particularly high-concentration impurities can be selectively removed, and the energy required for removing low-concentration impurities can be reduced. As a result, the energy required for SW IFT is reduced, and the power supply device can be made compact, so that a large power supply need not be used unnecessarily, which is economical. Here, the impurity that increases the voltage amplitude of the SW IFT waveform is preferably an impurity that has at least the same signal intensity as the signal intensity of the chemical substance to be measured. Although impurities with a smaller mass number may be targeted, the energy required for SWIFT will increase, so impurities with a signal intensity of 50% or more of the signal intensity of the chemical substance to be measured should be targeted. Is preferred. '

The method for detecting a chemical substance according to the next invention includes an ion trapping step of confining an ion group including ions of the chemical substance to be detected by an electric field, a magnetic field, or other means, and a voltage amplitude as the included frequency increases. And a mass spectrometry step of measuring the mass of the chemical substance to be detected or a fragment thereof by applying a SWIFT waveform with a reduced value to the ion group to remove impurities.

In the method for detecting a chemical substance according to the present invention, an impurity having a large mass number is supplied with the same energy as an energy given to an impurity having a small mass number. In general, the orbital resonance frequency in an ion trap is a function of the mass number. As the mass number increases, the frequency decreases and the frequency interval corresponding to mass interval 1 also decreases. On the other hand, the conventional literature `` Development of a Capillary High-performance Liquid Chromatography Tandem Mass Spectrometry System Using SWIFT Technology in an Ion Trap / Ref lectron Time-of-flight Mass Spectrometer Rapid Communication in mass spectrometry, vol. 11 1739-1748 ( 1997) In the SWIFT waveform generation performed in (1), a SW IFT waveform is generated by converting a frequency spectrum having a constant voltage amplitude into a time domain by an inverse Fourier transform. In this case, a waveform of a sum of sine waveforms having a constant voltage amplitude is generated at a constant frequency interval. Therefore, in this case, as the mass number increases, the number of sine waves per mass number interval 1 decreases, so the energy per mass number interval 1 decreases. In other words, the energy applied to a molecule having a large mass number becomes relatively small.

On the other hand, in the present invention, since the voltage amplitude of the relatively small divided sine wave is increased and corrected, sufficient energy can be given to ions having a large mass number. Even impurities can be more reliably removed. Also, energy can be given to ions having a small mass number in a necessary and sufficient range, so that the use efficiency of energy can be increased. Furthermore, since a large power supply is not required, installation costs can be reduced.

The method for detecting a chemical substance according to the next invention is based on an ion trapping step of confining an ion group containing ions of a chemical substance to be detected by an electric field, a magnetic field, or other means, and a method of detecting the number of molecules to be removed by SWIFT. An arbitrary waveform generating step of generating a SWIFT waveform having a constant voltage amplitude distribution, and applying the SWIFT waveform to the ions confined in the ion trap means to remove the impurities, And a mass spectrometry step of measuring the mass of the target chemical substance or its fragment.

This chemical substance detection method is such that when the frequency spectrum of a SW IFT waveform whose voltage amplitude increases as the frequency decreases becomes smaller, the voltage amplitude per mass number becomes a substantially constant value when the mass number is converted to the horizontal axis. It is made to become. Therefore, almost constant energy can be given to molecules of any mass to be removed by SWIFT. As a result, sufficient energy can be given to ions having a large mass number, so that such impurities can be more reliably removed. In addition, for ions with a small mass number, the energy is necessary and Energy efficiency can be increased. Furthermore, since a large power supply is not required, installation costs can be reduced.

The method for detecting a chemical substance according to the next invention includes an ion trapping step of confining an ion group including ion ions of the target chemical substance to be ionized by an electric field, a magnetic field, or other means; Applying a SW IFT waveform that does not give a voltage amplitude to the ion group to remove impurities and leave a plurality of substances to be detected in a plurality of frequency bands corresponding to the mass number; And a mass spectrometry step for measuring the mass of the substance or the fragment. Since dioxins and their precursors contained in the exhaust gas from incinerators are extremely small, it is extremely important to improve their detection accuracy when controlling the incinerator combustion conditions in real time. In the method for detecting a chemical substance according to the present invention, impurities are removed by using a SWIFT waveform that does not provide a voltage amplitude in a frequency band corresponding to a plurality of detection target substances. Then, a plurality of chemical substances to be detected are simultaneously detected by the mass spectrometry means. As described above, since a plurality of chemical substances to be detected are detected simultaneously, for example, even if the accuracy of detecting each of the target substances is insufficient, dioxins and dioxins are included as a total of the plurality of chemical substances. Accurate measurement can be performed by determining the correlation between the parameters and evaluating the combustion state, and the accuracy of combustion control can be improved.

The method for detecting a chemical substance according to the next invention comprises: an ion trapping step of confining an ion group containing ions of a plurality of target chemical substances having different mass numbers by an electric field, a magnetic field, or other means; Applying a SW IFT waveform not giving a voltage amplitude to the ion group to remove impurities and leaving a plurality of chemical substances to be detected in a plurality of frequency bands corresponding to the mass number of the chemical substance; A fragmentation step of fragmenting the chemical substances to be detected in ascending order of chemical substances among the chemical substances to be output, and a mass spectrometry step of measuring the mass of the chemical substances to be detected or the fragments. .

In this chemical substance detection method, the mass number of multiple Fragmentation is performed in order starting from the smallest chemical substance to be detected. For this reason, fragmentation of the chemical substance to be detected having a small mass number can prevent a fragment of a substance having a mass number greater than that of the substance to be detected from being broken. As a result, all of the plurality of target substances can be detected, so that the sensitivity in mass spectrometry can be increased and more accurate measurement can be performed.

The method for detecting a chemical substance according to the next invention comprises: an ion trapping step of confining an ion group including ion ions of a plurality of target chemical substances having different mass numbers by an electric field, a magnetic field, or other means; Applying a SWIFT waveform that does not provide a voltage amplitude to the ion group to remove impurities and leave a plurality of detection target chemical substances in a plurality of frequency bands corresponding to the mass number of the target chemical substance; and Providing a TICKLE waveform including frequencies corresponding to at least two of the isotopes of the substance, and fragmenting at least two of the isotopes of the target chemical substance; and Mass spectrometry for measuring the mass of the substance or its fragment. In this method of detecting a chemical substance, a TICKLE waveform including frequencies corresponding to at least two of the isotopes of the target chemical substance is given, and at least two of the isotopes of the target chemical substance are detected. Fragment and submit to mass spectrometry. As described above, since multiple isotopes are used in mass spectrometry, detection accuracy can be improved even when only a trace amount of dioxins or their precursors is present in exhaust gas. Also, when used for combustion control in incinerators, control accuracy can be increased.

In the method for detecting a chemical substance according to the next invention, in the method for detecting a chemical substance, in the mass spectrometry step, at least two types of isotopes of fragments generated from the chemical substance to be detected are to be measured. It is characterized.

In this method of detecting chemical substances, at least two types of isotopes of fragments generated from the target chemical substance are subjected to mass spectrometry. As described above, since isotopes of a plurality of fragments are used in mass spectrometry, detection accuracy can be improved even when dioxins and their precursors are present in only a trace amount in exhaust gas. Ma In addition, when used for combustion control of an incinerator, the control accuracy can be increased.

The method for detecting a chemical substance according to the next invention is the method for detecting a chemical substance, wherein, before the ion trapping step, the ionization potential of the chemical substance to be detected is large. An ionization step of applying energy smaller than the sum of the dissociation energies of ions of the chemical substance to be detected to the chemical substance to be detected and ionizing the chemical substance to be detected is provided. In the chemical substance detection method according to the next invention, in the ionization step, the ionization potential is high, and energy equal to or less than a value obtained by adding 4 eV to the ionization potential is given to the detection target substance. It is characterized.

In the method for detecting a chemical substance according to these inventions, the ionization potential of the chemical substance to be detected is large, and the energy smaller than the sum of the ionization potential and the dissociation energy of the ions of the chemical substance to be detected is obtained. This is given to the chemical substance to be detected, and the substance to be detected is ionized. As a result, unnecessary fragments are not generated, and the remaining detection target chemical substance does not need to be destroyed, so that the detection sensitivity in mass spectrometry can be increased. Therefore, in combination with the effect of the chemical substance detection method described above, the detection sensitivity of the mass spectrometer can be further improved, and highly accurate measurement can be performed. And, in the combustion control of the incinerator, more precise control is possible. Furthermore, since the SW IFT voltage can be kept low, there is no need to provide a large power supply 1 without any need, and the production cost of the apparatus can be further reduced. Brief Description of Drawings

FIG. 1 is an explanatory diagram showing a chemical substance detection device according to Embodiment 1 of the present invention. FIG. 2 is a flowchart showing a chemical substance detection method according to Embodiment 1 of the present invention. FIG. 3 is an explanatory diagram showing the ion signal intensity distribution with respect to the RF voltage when the trap frequency is fixed, and FIG. 4 is a graph showing the ion signal with respect to the RF frequency when the RF voltage is fixed. FIG. 5 is an explanatory diagram showing a signal intensity distribution, and FIG. 5 shows a relationship between a SW IFT frequency and an amplitude, an ion signal, FIG. 6 is an explanatory diagram showing a frequency spectrum of a SWIFT waveform according to Embodiment 5 of the present invention, and FIG. 7 is a diagram showing a frequency spectrum of a conventional SWIFT waveform. FIG. 8 is an explanatory diagram showing a frequency spectrum of a SWIFT waveform according to the sixth embodiment of the present invention, and FIG. 9 is a diagram showing a SWIFT waveform according to the seventh embodiment of the present invention. FIG. 10 is an explanatory diagram showing a frequency spectrum, FIG. 10 is an explanatory diagram showing a frequency spectrum of a TICKLE waveform according to Embodiment 7 of the present invention, and FIG. FIG. 19 is an explanatory diagram in which a frequency spectrum of a TICKLE waveform according to the ninth embodiment of the invention is converted with a mass number as a horizontal axis. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail with reference to the drawings. It should be noted that the present invention is not limited by the embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same. Further, components in the following embodiments include those that can be easily assumed by those skilled in the art.

(Embodiment 1)

FIG. 1 is an explanatory diagram showing a chemical substance detection device according to Embodiment 1 of the present invention. The chemical substance detection device 100 includes an ion chamber 1, a gas introduction device 2, a vacuum ultraviolet light lamp 3 as ionization means, and a time-of-flight mass spectrometer 4 as mass analysis means. ing. The ionization chamber 1 is provided with an RF ion trap device 10 having an RF (Radio Frequency) ring as an ion trap means. In this method, the detection target chemical substance in the ionized exhaust gas is confined in the trap 11 by a high-frequency electric field formed inside.

Means that confine ions inside by electric or magnetic fields or other electromagnetic forces can be used. The electric field, the magnetic field, and the like may be used alone, or may be used in an appropriate combination. With such ion trap means There are several types, and among them, the above-mentioned RF ion trap device 11 in which a high-frequency electric field is formed is preferable because it is relatively easy to handle. As other ion trap means, a Penning trap using a DC voltage and a static magnetic field can be used in addition to the RF type.

The RF ion trap device 10, which is an ion trap means, includes a first end cap 12, a second end cap 13, and an RF ring 14, and is a three-dimensional quadrupole type. As shown in FIG. 1, the RF ring 14 is disposed inside the first end cap 12 and the second end cap 13. A high-frequency power supply 21 for applying a trap voltage is connected to the RF ring 14, and applies a high-frequency voltage as a trap voltage to the RF ring 14. Due to this high frequency, chemical substances to be detected and other substances in the ionized exhaust gas are trapped in the trap 11 1. An arbitrary waveform generator 20 as an arbitrary waveform generating means is connected to the first and second end caps 12 and 13, and a specific frequency is applied between both end caps at the time of SWIFT and TICKLE described later. Apply voltage.

The gas introduction device 2 is provided with a gas injection tube 5, and the gas injection tube 5 is formed by an on-off valve using an orifice such as a pulse valve or a capillary tube. The exhaust gas G s from the incinerator and the like introduced into the gas injection pipe 5 is introduced into the ionization chamber 1. A heater 6 is provided around the gas injection pipe 5. The heater 6 is a heating device for preventing the chemical substance to be detected from adhering to the inner wall of the gas injection pipe 5.

The ionization chamber 1 is provided with a vacuum ultraviolet light lamp 3 as ionization means for applying energy to the detection target chemical substance to perform ionization. Vacuum ultraviolet light lamp 3, A r, K r, and rare gas such as _{_{X e, H 2, 0 2}} , C 1 2 etc. A r, generating vacuum ultraviolet light L by discharge gas added to the H e I do. In this embodiment, Lymana light having a wavelength of 121.6 nm from hydrogen plasma is used.

The vacuum ultraviolet light lamp 3 generates vacuum ultraviolet light by changing the type of gas to be discharged. The amount of photon energy of external light can be changed. For this reason, it is possible to apply a photon energy that is larger than this and does not dissociate the target chemical substance according to the ionization potential of the target chemical substance. As a result, ionization of a mixed substance having an ionization potential higher than the photon energy can be prevented, and fragmentation of the detection target chemical substance can be suppressed.

Further, as the ionization means, a laser or a harmonic thereof can be used instead of the vacuum ultraviolet light lamp 3. In this case, by using a tunable laser, the amount of generated photon energy can be changed to select a substance to be ionized. A well-known tunable laser can be used. Incidentally, vacuum ultraviolet light having a wavelength of 50 nm or more and 200 nm or less can be applied to the present invention, more preferably 100 nm or more and 200 nm, and the generation of unnecessary fragments is further reduced. From the viewpoint of suppression, the range of 1 1 2 11 111 or more and 1 38 nm is desirable.

Further, as a means for applying energy to the chemical substance to be detected and ionizing the same, a laser or an excimer lamp having a wavelength of vacuum ultraviolet light may be used. Further, for example, ions such as He ions may be ejected by a particle accelerator to collide with a detection target chemical substance contained in the sample gas in the ionization chamber 1. Furthermore, the electron beam may be separated at each sector to extract an electron beam having an energy of about 10 eV and collide with the detection target chemical contained in the exhaust gas in the ionization chamber 1.

The time-of-flight mass spectrometer 4, which is a mass spectrometer, specifies the chemical substance to be detected by measuring the mass of the ion of the chemical substance to be detected in the exhaust gas ionized in the ionization chamber 1. The ionized chemical substance to be detected is introduced into the mass spectrometer 4 by applying a pulsed extraction voltage to the second end cap 13 of the RF ion trap device 10, and flies through the mass spectrometer 4. . The flying ions are detected by the ion detector 30, and the signal detected here is amplified by the preamplifier 31 and then taken into the data processor 32 for data processing. Note that, in the present embodiment, a microchannel plate is used for the ion detector to increase the ion detection sensitivity. Mass spectrometer 4 Measure line time. Since there is a high-level correspondence between the time of flight and the mass of the flying substance, the mass of the flying substance is detected from the time of flight, and the substance is identified from this mass.

Next, a procedure for detecting a precursor to be detected in exhaust gas using the chemical substance detection apparatus 100 will be described with reference to FIG. Here, FIG. 2 is a flowchart showing a method for detecting a chemical substance according to Embodiment 1 of the present invention. First, the exhaust gas Gs of the incinerator is introduced into the ionization chamber 1 (step S101). Next, the vacuum ultraviolet light lamp 3 irradiates vacuum ultraviolet light L to the exhaust gas G s introduced into the ionization chamber 1, and the exhaust gas G s is ionized by receiving photon energy from the vacuum ultraviolet light L. (Step S102). Here, the ionization potential of the precursor to be inspected is in the range of 8.5 to 10 OeV. Further, as described above, the vacuum ultraviolet light used in the present embodiment has a wavelength of 121.6 nm, and its photon energy is 101.5 eV. As described above, since the energy is applied to a degree slightly larger than the ionization potential of the precursor, the precursor can be ionized without giving extra energy to the precursor.

As a result, it has become possible to efficiently measure the ionized precursor, which is a target chemical substance to be detected. This is because the generation of fragments is very small in ionization by vacuum ultraviolet light, so that almost all ionized precursors can be measured by the mass spectrometer 4. In particular, this effect is significant because only a very small amount of precursor is present in the exhaust gas from the incinerator. In addition, a decrease in trap efficiency of the trap 11 can be suppressed. Here, when there are many fragmented ions, the potential created by the ions generated by the ions confined in the trap 11 acts to cancel the potential of the trap. However, in the ionization using the vacuum ultraviolet light, the generation of extra fragment ions can be extremely suppressed, so that the reduction in the trapping efficiency of the ion trap device 11 can be reduced.

Further, the SWIFT voltage described below can be kept low. here, SW IFT is an operation to change the trajectory of the ion by applying a voltage waveform having a specific frequency between the first end cap 12 and the second end cap 13 of the trap 11 to remove impurities. Say. In the ionization method, which generates a lot of fragments, the mass number to be removed in the process of SW IFT generates a large amount of fragments with the precursor to be detected or the other molecule as a parent molecule. I will. Since a very large voltage is required to remove this by SW IFT, a high-output SW IFT voltage generator (arbitrary waveform generator) is required. On the other hand, if the SW IFT voltage is increased, molecules having a mass number other than the mass number to be exfoliated will also be exfoliated, so that the precursor to be retained will be exfoliated. As a result, the accuracy of mass spectrometry is reduced. '

In the ionization according to the present invention, since the generation of fragments is very small, the number of fragments to be removed in the process of SW IFT becomes extremely small. As a result, since the SWIFT voltage is kept low and the remaining precursor is not destroyed, the above problems can be almost avoided. In addition, when TICKLE described later is applied to the parent molecule remaining after SWIFT or when COOLING is performed, fragments are generated from various parent molecules by the ionization method with many fragments. As a result, fragments other than the target precursor were included as impurities, resulting in a decrease in the accuracy of mass spectrometry. However, according to the ionization method of the present invention, since the number of fragments generated during ionization is extremely small, this problem can be substantially avoided.

Next, SW IFT will be described. This is an operation to remove unnecessary substances other than the target chemical substance present in the exhaust gas. For this purpose, the orbital resonance frequency of the material to be removed by the arbitrary waveform generator 20 is placed between the first end cap 12 and the second end cap 13 of the RF ion trap device 10. A voltage is applied at a wide band frequency. Thereby, the impurity removing means according to the present invention is formed. The orbital resonance frequency corresponding to the frequency of the mass number of the chemical substance to be detected is eliminated from the frequency in the wide band. This removes The material to be shaken has a large amplitude, collides with the wall of the RF ion trap device 10, loses electric charge, and does not exist as ions. The chemical to be detected remains trapped in the trap 11 by the trap voltage applied to the RF ring 14. Such an operation is referred to as SWIFT. By this operation, impurities other than the chemical substance to be detected can be removed (step S103).

Next, TICKLE will be described. TICKLE is an operation in which the chemical substance to be detected is fragmented to separate the chemical substance to be detected from the impurity whose mass number is close to that of the chemical substance to be detected. Then, the target chemical substance is identified by measuring the mass number of a fragment generated from the molecule of the target chemical substance that is the parent molecule. Also, by measuring the amount of the fragment, the concentration of the chemical substance to be detected can be obtained. TICKLE, unlike the above-described SWIFT, applies a voltage between the first end cap 12 and the second end cap 13 at a frequency corresponding to the orbital resonance frequency of the target chemical substance to be detected, which is the parent molecule. At this time, the voltage of the frequency is applied between the end caps by the arbitrary waveform generator 20. This constitutes the fragmentation means according to the present invention. Then, ions of the chemical substance to be detected collide with other substances coexisting in the trap 11 to fragment the chemical substance to be detected. This completes fragmentation by TICKLE (step S104).

When the fragmentation by TI CKLE is completed, the application of the voltage to the RF ring 14 is stopped, and a pulsed extraction voltage is applied to the second end cap 13, so that the ions of the fragmented chemical substance to be detected are massed. Pull out to analyzer 4 side (step S105). The ions of the chemical substance to be detected fly in the mass spectrometer 4, and the time of flight is measured by the mass spectrometer 4. As described above, since there is an altitude correspondence between the time of flight and the mass of the flying material, the mass of the flying material is detected from the time of flight, and the material is identified from this mass (step S106). ), The measurement ends (step S107).

The time-of-flight mass spectrometer used in this embodiment is a single Since the measurement is completed, there is the advantage that the measurement time is very fast and the response is excellent. Therefore, it is particularly suitable for controlling combustion conditions in real time in an actual plant. As other mass spectrometry means, mass spectrometry means such as an electric field type or an RF coil type can be used. In particular, since the RF coil type only needs to provide an ion detector at the exit of the trap 11, a mass spectrometer can be configured with a simple structure.

(Embodiment 2)

The chemical substance detection device 100 according to the present invention ionizes a substance to be measured by directly irradiating exhaust gas introduced into the trap 11 with vacuum ultraviolet light. Then, SWIFT and TICKLE are applied to this to fragment the ions of the target substance. For this reason, SWIFT and fragmentation may not always succeed under the same conditions as the conventional ionization. Thus, here, the conditions of SWIFT and TICKLE will be described. FIG. 3 is an explanatory diagram showing an ion signal intensity distribution with respect to an RF voltage when a trap frequency is fixed. FIG. 4 is an explanatory diagram showing the ion signal intensity distribution with respect to the RF frequency when the RF voltage is fixed.

In the ionization using a combination other than vacuum ultraviolet light, which has been used so far, the chemical substance to be detected is ionized outside the trap 11. When fragmenting the chemical substance to be detected, a collision gas such as an inert gas or a nitrogen gas is supplied into the trap 11 from the outside to fragment the chemical substance to be detected. Therefore, almost no atmospheric components such as water vapor and oxygen contained in the exhaust gas as the gas to be measured were present in the trap 11. Therefore, the ion signal intensity distribution as shown in FIG. 3 (a) and FIG. 4 (a) was shown.

However, in the ionization method according to the present invention, the exhaust gas introduced into the trap 11 is directly irradiated with vacuum ultraviolet light to ionize the chemical substance to be detected. Therefore, the trap 11 contains atmospheric components such as water vapor and oxygen present in the exhaust gas. In an environment where such atmospheric components such as water vapor and oxygen coexist with the chemical substance to be detected, a TI CKLE voltage described later is applied to fragment the chemical substance to be detected. Fragmentation may result in a condition where fragments cannot be trapped. For example, when the RF voltage exceeds 1500 V, fragments can no longer be trapped (Fig. 3 (b)). When the RF frequency is lower than 1.0 MHz, fragments can no longer be trapped (Fig. 4 (b)). Here, the trap condition refers to a value of an RF voltage and an RF frequency applied to the RF ring 14. This is because the water vapor, that is, water molecules and oxygen molecules have polarities, and the orbit of the fragmented chemical substance to be detected increases, so that the ions collide with the wall surface of the trap 11 and lose charge. It is thought that this is the cause.

Therefore, it is necessary to adjust the trapping conditions so that the fragmented ions of the chemical substance to be detected can be trapped even when the water molecules and the oxygen molecules coexist. For example, using the TCB (mass number 180, 182, 184) as the parent molecule, a fragment from which chlorine was removed (mass number 145, 147), a fragment from which two chlorine and one hydrogen were removed ( Let us consider the case of detecting fragments (mass number 74) with mass numbers of 109 and 1 1 1) and 3 chlorines and 1 hydrogen. In the conventional ionization method, when the RF frequency was 1. OMHz, the fragment ions could be trapped appropriately when the RF voltage was set to be between 1,000 V and 200 OV (see FIG. 3 (a)).

In the coexistence of oxygen and water molecules, under the same frequency conditions, trapping can be performed favorably when the RF voltage is 700 V or more and 130 OV or less, and more stable when the RF voltage is 900 V or more and 110 OV or less. Ions can be trapped (see Fig. 3 (b)). When the RF voltage is set to 160 OV, the RF frequency of 1.OMhz is appropriate in the conventional method, but in this method, the RF frequency is 1.2 MHz or more and 1.7 MHz or less. Within this range, fragment ions can be stably trapped. Furthermore, when the RF frequency is in the range of 1.4 MHz to 1.6 MHz, fragment ions can be trapped more stably (see Fig. 4 (b)).

(Embodiment 3) At the time of SWIFT, it is necessary to increase the trapping efficiency of the target substance, which is the parent molecule with a high mass. On the other hand, during TI CKLE, it is necessary to increase the trapping efficiency of fragmented measurement objects with low mass numbers. Therefore, at the time of SWIFT, the setting is such that the energy value applied to the RF ring 14, that is, the product of the RF voltage and the RF frequency is increased. And at TI CKLE, it is set so that the product of RF voltage and RF frequency becomes small. By doing so, the trapping efficiency of the target substance and its fragments during SWIFT and TI CKLE can be increased.

For example, assuming that the RF frequency is constant at 1 MHz, trap at 1600 V during SWIFT and 1000 V during TICKLE. Alternatively, the RF voltage may be kept constant at 1600 V, and the RF frequency may be trapped at 1.4 MHz during SWIFT and may be trapped at 1.0 MHz during TICKLE. You can also change both the RF frequency and the RF voltage. This change may be changed in a step response or may be changed gradually. In addition, since the chemical substance to be detected is dissipated from the trap 11 to the outside with a certain life, it is preferable that the time required for TICKLE be appropriately shortened. Specifically, it is preferable to increase the T I CKLE voltage.

Since the mass of the target chemical is smaller after fragmentation by TI CKLE than before fragmentation, the RF voltage applied to the RF ring 14 should be set at least after the end of TI CKLE. It is necessary to increase the RF frequency. However, if the RF voltage applied to the RF ring 14 is decreased or the RF frequency is increased, the trapping efficiency of fragments having a small mass number decreases. Therefore, if much time elapses after the end of TIC KLE in this state, the number of the fragments decreases, and the detection sensitivity in the mass spectrometer 4 decreases. Therefore, it is preferable to switch as described above immediately after the time for fragmentation of the target chemical substance has elapsed after the input of the TICKLE waveform. (Embodiment 4)

In SW IFT, substances other than the chemical substance to be detected are removed, but the mass that must be removed at this time is the same as the mass number of fragment ions generated when the chemical substance to be detected is fragmented. Is an impurity having This is because, in the mass spectrometry after fragmentation by TICKLE, this impurity is also measured together with the fragment ion, and as a result, the measurement accuracy of the target chemical substance is reduced. In addition, when impurities other than the above are present in a large amount in the trap 11, the trap 11 is saturated and the trap efficiency is reduced, so that impurities other than the chemical substance to be detected are minimized during SW IFT. It is better to remove it. However, in order to remove all impurities other than the target chemical, a SWIFT waveform having a frequency component corresponding to a very wide mass number range must be applied. However, since the SWIFT waveform having a wide range of frequency components has low energy per unit frequency, the energy that can be added to a molecule having a certain mass number is also small. As a result, the efficiency of removing impurities is reduced, and the detection accuracy of the target chemical substance is also reduced. Therefore, when a SW IFT waveform having a wide range of frequency components is added, the high-frequency generator 21 that is the SWIFT waveform generation source is made to have high performance, the output of an amplifier that amplifies this output is increased, or the amplification is performed. It is necessary to widen the frequency band. As a result, the device becomes large and expensive.

Therefore, the mass spectrum of the impurities contained in the exhaust gas is examined, and the impurities are removed using a SW IFT waveform having a frequency component corresponding to the range of the mass number that must be removed at a minimum. The range of the mass number that must be removed at a minimum can be determined by, for example, making the signal intensity of the mass spectrum include impurities having a certain value or more. This constant value should be at least as high as the signal intensity of the chemical substance to be measured, and it is preferable to target impurities with a signal intensity higher than this value. Although impurities with even lower mass numbers may be targeted, the energy required for SWIFT increases. Therefore, chemical substances to be measured It is preferable to target impurities having a signal intensity of 50% or more of the signal intensity of the above.

In one incinerator example, for example, the range where the mass number is 48 or more and 355 or less is the minimum range that must be removed, so impurities are removed by SWIFT waveforms having a frequency component corresponding to this range. I do. In this way, the chemical substance to be detected can be measured with practically sufficient accuracy without increasing the energy input to the trap 11 indiscriminately. This eliminates the necessity of using a large device unnecessarily, and reduces the cost of the device.

(Embodiment 5)

FIG. 5 is an explanatory diagram showing the relationship between SWIFT frequency and amplitude and the relationship between ion signal and mass number. Here, the mass number in FIG. 5 corresponds to the SWIFT frequency in FIG. FIG. 6 is an explanatory diagram showing a frequency spectrum of a SWIFT waveform according to Embodiment 5 of the present invention. The frequency spectrum represents the intensity (voltage amplitude) of the SWIFT waveform or TICKLE waveform as a function of the frequency of the SWIFT waveform or the like. To remove very high concentration impurities, it is necessary to apply a very high SWIFT voltage, but in the conventional SWIFT, the frequencies corresponding to all mass numbers are applied with the same voltage amplitude. That is, the SWIFT voltage is determined by the voltage required to remove the highest concentration impurity. For this reason, when removing very high concentration impurities, very high voltage amplitude is required as a whole, and energy use efficiency is reduced. In addition, power supplies and devices need to have large capacities, resulting in increased costs. Furthermore, in order to leave the parent molecule, which is the chemical substance to be detected, the frequency band corresponding to the mass number of the substance to be detected is reduced from the SWIFT waveform, but a high voltage amplitude is obtained. In the case of stamping, the range of the mass number actually remaining becomes smaller even if the same frequency band is excluded. As a result, there is also a problem that the detection target chemical substance is partially removed, and the detection accuracy is reduced. This is because the frequency spectrum of the actual SWIFT waveform is not an ideal rectangle as shown by the solid line in Fig. 5 (a), but is a break in Fig. 5 (b). This is because the shape is slightly divergent as shown by the line. In other words, since the frequency spectrum of the SWIFT waveform actually has a divergent shape, the frequency band corresponding to the mass number of the target chemical substance indicated by ΔF in the figure becomes smaller, resulting in lower detection accuracy. It is.

For this reason, as shown in FIG. 6, the voltage amplitude of the SWIFT waveform having a frequency corresponding to the mass number of the high-concentration impurity is increased, and the voltage amplitude is reduced in a portion where the impurity concentration is low. In this way, particularly high-concentration impurities can be selectively removed. Here, the impurity that increases the voltage amplitude of the SWIFT waveform is preferably an impurity having at least the same signal intensity as the signal intensity of the chemical substance to be measured. Although impurities with even lower mass numbers may be targeted, the energy required for SWIFT is increased. For this reason, it is preferable to target impurities having a signal intensity of 50% or more of the signal intensity of the chemical substance to be measured. As a result, the voltage amplitude of the SWIFT waveform can be suppressed as a whole, so that the energy use efficiency can be increased and impurities can be removed. In addition, since a power supply having a small capacity can be used, the size of the power supply can be reduced, and the cost can be reduced. Furthermore, even if the SWIFT operation is performed, the detection target chemical substance can be reliably left, so that the detection accuracy of the mass spectrometer 4 can be increased.

(Embodiment 6)

FIG. 7 is an explanatory diagram showing a frequency spectrum of a conventional SWIFT waveform. FIG. 8 is an explanatory diagram showing a frequency spectrum of a SWIFT waveform according to Embodiment 6 of the present invention. Here, (b) in both figures is obtained by converting the frequency spectrum of the SWIFT waveform on the horizontal axis of the mass number, that is, as a function of the mass number. A normal SWIFT waveform is generated by performing an inverse Fourier transform on a rectangular frequency spectrum whose amplitude does not change even if the ion resonance frequency increases (Fig. 7 (a)). The SWIFT waveform at this time is a waveform in which a resonance frequency corresponding to the mass number of the impurity to be removed is superimposed. This waveform is ideally a continuous waveform containing all orbital resonance frequencies corresponding to a certain mass range. However, in practice, since the inverse Fourier transform is always performed based on data of a finite number of resonance frequencies, the frequency components included in the obtained SW IFT waveform are discrete, and the frequency pitch is constant. Conversely, when this is converted into a mass number, the frequency pitch is coarse in the region with a large mass number and fine in the region with a small mass number.

Using such a SW IFT waveform, ions with a low mass number are given an amplitude at a high energy density, and conversely, large ions and a small ion are given an amplitude only at a small energy density ( Fig. 7 (b)). For this reason, ions with a small mass number can be easily broken, but ions with a large mass number are not easily broken and remain as impurities. In addition, extra fragments are generated by T I KCL, thereby reducing the accuracy of mass spectrometry.

Therefore, as the resonance frequency corresponding to the mass number of the ion increases, a SWIFT waveform generated by performing an inverse Fourier transform on the frequency spectrum with the reduced voltage amplitude is used (FIG. 8 (a)). In this way, sufficient energy can be given to ions with a large mass number (Fig. 8 (b)). In other words, since a SW IFT waveform having a constant voltage amplitude distribution can be given regardless of the mass number of the molecule to be removed by SW IFT (Fig. 8 (b)), even if the ion has a large mass number It can be removed more reliably. In addition, energy can be given to ions having a small mass number in a sufficient range, so that the energy use efficiency can be increased. In addition, since a large power supply is unnecessary, installation costs can be reduced.

(Embodiment 7)

FIG. 9 is an explanatory diagram showing a frequency spectrum of a SW IFT waveform according to Embodiment 7 of the present invention. FIG. 10 is an explanatory diagram showing a frequency spectrum of a TICKLE waveform according to Embodiment 7 of the present invention. When measuring chemical substances to be detected, such as dioxin precursors, with this chemical substance detection device 100, simultaneous measurement of multiple chemical substances to be detected can increase the detection accuracy. Wear. Particularly, since the precursors of the dioxins contained in the exhaust gas of the incinerator are extremely small, it is extremely important to improve the detection accuracy when controlling the combustion conditions of the incinerator in real time.

Therefore, in order to simultaneously measure a plurality of chemicals to be detected, the voltage amplitude in the resonance frequency band corresponding to the mass number of the chemicals to be detected was set to 0 in SWI FT, that is, the SWI without voltage amplitude was applied. The frequency spectrum of the FT waveform is used (Fig. 9). Then, an inverse Fourier transform is performed on the frequency spectrum of the SWIFT waveform to generate a SWIFT waveform. When SWIFT is performed using the SWIFT waveform after the inverse conversion, the chemical substance to be detected remains trapped in the trap 11 of the ion trap device 10 and can be separated from other impurities.

Next, the TICKLE frequency spectrum, which has a large amplitude in the frequency band corresponding to the mass number of the target substances, is inversely Fourier-transformed and the TICKLE waveform is used to generate the target objects. Fragment the substance (Fig. 10 (a)). Then, the ions of the fragmented chemical substance to be detected can be measured by the mass spectrometer 4 (see Fig. 1) to identify the chemical substance to be detected and determine its concentration. In addition, TI CKLE is applied by a TI CKLE waveform generated by performing an inverse Fourier transform of the TI CKLE frequency spectrum having a large amplitude in a range including all the frequencies corresponding to the mass numbers of the plurality of detection target chemical substances. (Fig. 10 (b)). Furthermore, the respective frequencies corresponding to the mass numbers of the plurality of chemical substances to be detected may be provided singly and sequentially.

(Embodiment 8)

As described above, it is preferable to simultaneously measure a plurality of chemical substances to be detected because detection accuracy can be increased. When measuring multiple chemical substances to be detected simultaneously, there are the following problems. For example, to obtain a fragment pattern with TCB (trichlorobenzene) and DCB (dichlorobenzene) as parent molecules at one time, the TCB fragment has a mass number of 145 and a DCB with a mass number of 146. The mass numbers differ only by 1. Therefore, the TCB and DCB are When CKLE is applied, the fragment of the adjacent TCB may be damaged by the TI CKLE frequency of the DCB. In this case, the TCB is fragmented to separate the TCB from impurities having a mass number similar to that of the TCB, and it is no longer possible to determine the TCB concentration or the like by measuring the signal of the fragment. As a result, the accuracy of TCB detection is reduced. Therefore, in the TI CKLE according to the seventh embodiment, various precautions are required, such as accurately giving a frequency corresponding to the mass number and appropriately adjusting the TI CKLE voltage. Moreover, even with such precautions, fragmentation may not be performed properly.

Therefore, in the present embodiment, the detection target chemical substance having a small mass number is broken by TI CKLE and fragmented, and the detection target chemical substance and impurities within the mass number range of the detection target chemical substance are removed. deep. Then, the TI CKLE is applied to the chemical substance having a larger mass number to detect the chemical substance having a larger mass number within the range of the mass number in which the chemical substance having the smaller mass number was present. Generate a fragment of the target chemical.

With this configuration, when the detection target chemical substance having a large mass number is fragmented, the detection target chemical substance having a small mass number has already been fragmented. Fragments of the target are not destroyed by the TI CKLE, a chemical with a low mass number. Therefore, even if a plurality of chemical substances to be detected having different mass numbers are simultaneously detected, highly accurate measurement can be performed.

Specifically, TCB (mass number 180, 182, 184, 186), DCB (mass number 146, 148, 150) ぉ 1〇8 (monochrome benzene: mass number 1 12, 1 14) are detected simultaneously Consider the case. Prior to TI CKLE, SWIFT removes these impurities and removes other impurities. Next, in order to fragment the MCB, a TI CKLE frequency corresponding to the mass number of the MCB is applied to the first and second end caps 12 and 13 to generate a 77 mass fragment. At this time, the inside of the trap 11 of the ion trap device 10 The substance of mass number 112 to 114 does not exist.

After fragmenting the MCB, the TICBLE frequency corresponding to the mass number of the DCB is applied to fragment the DCB. This fragment has a mass number of 111 and 113 with one chlorine separated from DCB and a mass of 75 with two chlorine and one hydrogen separated. Finally, a frequency corresponding to the mass number of the TCB is applied to fragment the TCB. The fragments generated at this time are those with a mass number of 145, 147 and 149 where one chlorine is separated, those with a mass number of 109 and 111 where two chlorines and one hydrogen are separated, and three chlorines. And one hydrogen separated with a mass number of 74. The above fragments are applied with respective TICKLE frequencies sequentially with a certain time difference.

After the fragmentation of the chemical substance to be detected is completed, the voltage of the fragment ions in the trap 11 is changed to C 0 01 in without applying a voltage between the first and second end caps 12 and 13 of the ion trap device 10. Cooling means that fragment ions collide with a neutral gas in the trap 11 and lose energy, whereby the fragment ions are cooled. The accuracy of mass measurement by the mass spectrometer 4 can be improved by using Coo ling.

After the completion of Cooling, the fragment is guided to the mass spectrometer 4 by applying an extraction voltage to the second end cap 13 and the mass thereof is measured, whereby the concentration of the chemical substance to be detected can be measured. Specifically, the concentration of MCB can be obtained by selecting the fragment signal intensity of mass number 77, and the concentration of DCB can be obtained by selecting the fragment signal intensity of mass numbers 113 and 75. The concentration of TCB can be determined by selecting a mass number that does not overlap with the above-mentioned MCB and DCB fragments, such as the signal intensity of mass numbers 145, 147, 149, 109, and 74.

In addition, if the mass numbers of the fragments generated from the chemicals to be detected do not overlap, the chemicals to be detected, for example, TCB and TCP, can be simultaneously destroyed by the TI CKLE waveform. For example, by breaking the MCB and MCP first, then breaking the DCB and DCP, and finally breaking the TCB and TCP, six types of detection Elephant chemicals can be measured simultaneously. In this case, since two types of fragments are used, the time required for fragmentation is approximately three times that of one type.

(Embodiment 9)

Some target chemicals have isotopes, and even the same target chemical has a different mass number. For example, MC B has isotopes with mass numbers of 112 and 114. This is because there are two kinds of chlorine, 35 and 37, in the mass number of chlorine bonded to the benzene ring. In the detection target chemical substance having such an isotope, the density of the target substance is lower than the total density of the target substance, and thus the density of the target substance is lower than that of the entire target substance. If only the mass number is used as the substance to be measured in the mass spectrometer 4, the measurement sensitivity is reduced.

Taking the above MCB as an example, if only the MCB with a mass number of 11 is targeted for measurement, the MCB with a mass number of 114 will not be measured. As a result, the concentration is detected lower by the MCB with a mass number of 114, which was not measured as the whole MCB. In particular, since the concentration of dioxin precursors, which are the chemical substances to be detected in the exhaust gas from incinerators, is extremely low, it is necessary to increase the detection sensitivity even a little. Therefore, if at least two isotopes of at least two chemicals to be detected are fragmented, the above problem of the decrease in measurement sensitivity can be avoided. Here, the isotope of TCB will be described as an example, but the object of application of the present invention is not limited to TCB, and any chemical substance to be detected having an isotope can be applied. FIG. 11 is an explanatory diagram in which the frequency spectrum of the TICKLE waveform according to the ninth embodiment of the present invention is converted with the mass number on the horizontal axis. FIG. 3A shows the distribution of isotopes in the TCB ion.

For example, the fragmentation of all isotopes of the target chemical substance, the removal of theoretically low-concentration isotopes from all isotopes, or the detection of target substances by removing mass numbers with a high percentage of impurities It can fragment an isotope of a substance. At this time, the TICKLE waveform contains at least two chemicals to be detected. An inverse Fourier transform of a frequency spectrum that gives a large amplitude over a wide resonance frequency band and includes mass numbers for all isotopes of quality can be used (Fig. 11 (b)). .

In addition, since the resonance frequency has a certain range in the mass number that affects the ion, if a frequency spectrum with a constant amplitude is used, the isotopes with the largest and smallest mass numbers are less likely to be subjected to TI CKLE, and the middle Isotopes are relatively susceptible to TI CKLE. For this reason, if the frequency spectrum is set so that the voltage amplitude at the part where the mass number of the chemical substance isotope to be detected is the largest and the part where the mass number is the smallest is almost constant for all of the multiple isotopes targeted by TI CKLE. TI CKLE can be applied. Thereby, fragmentation can be performed substantially uniformly. In addition, the frequency spectrum in which the voltage amplitude is large in the part where the mass number is the largest and the part where the mass number is small among the isotopes to be fragmented, and the voltage amplitude in the part where the mass number is medium is relatively small (The solid line in Fig. 11 (c)). Further, in an isotope having a relatively low ion signal intensity, a frequency spectrum in which the voltage amplitude is smaller than that in an isotope having a relatively high ion signal intensity may be used (first example). 1 (dashed line in Fig. (C)).

On the other hand, a large amount of impurities having a mass number substantially the same as a certain isotope may exist. For example, suppose that a large amount of impurities having the same mass number as the TCB isotope having a mass number of 180 in FIG. 11 (d) existed. In such a case, a high-precision measurement may be performed by fragmenting a plurality of isotopes excluding the isotope and not fragmenting a large amount of impurities. In this case, from the isotopes (here, the isotopes of TCB), a plurality of isotopes with few impurities in the same mass number are selected, and a plurality of isotopes are selected from the plurality of resonance frequencies corresponding to the mass number. A TICKLE waveform obtained by inverse Fourier transforming a frequency spectrum can be used (Fig. 11 (d)).

(Embodiment 10)

Isotopes also exist in the target chemical, but fragments of the target chemical Also have isotopes. Therefore, the same problem as described in the eighth embodiment exists for the measurement of fragments. Conventionally, the concentration of the target chemical substance was estimated by measuring the concentration of the target chemical substance with only one fragment or by matching the appearance pattern of the fragments.

However, sufficient sensitivity cannot be measured by measuring only one isotope of a fragment in a substance that exists only at a very low concentration, such as a dioxin precursor contained in the exhaust gas of an incinerator. . In addition, even for pattern matching using multiple fragments, the absolute amount of fragments is small with only one isotope, which is insufficient for statistically estimating the concentration.

Therefore, at least two types of isotopes of fragments generated from the chemical substance to be detected are measured. Specifically, of the spectrum (signal voltage) of a fragment, the sum of the maximum values of the spectra of multiple isotopes that appear, or the sum of the areas of the spectrums of multiple isotopes that appear, is calculated as Used as the measured value of mass spectrometer 4. In this way, all isotopes of a fragment can be used, so that the measurement sensitivity can be increased in the measurement by the mass spectrometer 4 even when the concentration of the substance to be measured is extremely low. When there is a spectrum with a large noise component, such as when an impurity fragment appears in the mass number of a certain isotope, the mass number of the isotope excluding the spectrum of the isotope is calculated. It suffices to select and determine the concentration of the measurement object. In this way, noise such as impurities can be eliminated, so that more accurate measurement can be performed.

As described above, in the chemical substance detection device according to the present invention, when the detection target chemical substance is ionized, the ionization potential is larger than the ionization potential of the detection target chemical substance and the ionization potential of the detection target chemical substance. Ion dissociation energy An energy smaller than the sum of the dissociation energy and the ion is given to the chemical substance to be detected. For this reason, the target chemical substance can be ionized without being destroyed, and the generation of unnecessary fragments that are a problem when removing impurities by SW IFT is extremely small. Therefore, it is not necessary to remove the remaining chemicals to be detected. Can be higher. Furthermore, when removing impurities, only a SW IFT waveform is given, so that impurities can be removed quickly. As a result, the detection speed of the target chemical substance can be increased, which is suitable for actual incinerator control.

Also, in the chemical substance detection device according to the present invention, the chemical substance to be detected is fragmented by the fragmentation means for giving a TICKLE waveform, so that impurities in the frequency band corresponding to the mass number of the chemical substance to be detected are included. Even if there is, measurement can be performed accurately by eliminating this effect. In addition, since fragments generated during ionization are extremely small, when the chemical substance to be detected is fragmented, the target chemical substance to be detected can be efficiently fragmented. As a result, the detection sensitivity of the mass spectrometer can be increased, and more precise combustion control can be performed.

In the chemical substance detection device according to the present invention, when energy is applied to the chemical substance to be detected by the ionization means, the value is higher than the ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential. In the case where the substance to be detected is ionized by the energy of light, the wavelength is set to 5 nm or more and 200 nm or less. Therefore, impurities can be removed without generating unnecessary fragments. And since such a light uses a vacuum ultraviolet lamp, it is easy to handle and the configuration of the device can be simplified.

Further, in the chemical substance detection device according to the present invention, the voltage amplitude of the SW IFT waveform having a frequency corresponding to the mass number of the impurity present at a high concentration that gives a signal intensity higher than the specific signal intensity is increased, The voltage amplitude was reduced in the portion where the impurity concentration was low. Therefore, particularly high-concentration impurities can be selectively removed, and the impurities can be selectively removed, so that the energy required for SW IFT can be reduced. This makes it possible to reduce the size of the power supply device, so that there is no need to use a large power supply indiscriminately, which is economical.

In the chemical substance detection device according to the present invention, more energy is given to impurities having a large mass number than energy given to impurities having a small mass number. In the chemical substance detection device according to the present invention, the frequency is low. W

37 When the frequency spectrum of the SWIFT waveform whose voltage amplitude was increased as the distance became larger and the mass number was converted to the horizontal axis, the voltage amplitude per unit mass was made to be a substantially constant value. For this reason, sufficient energy is given to impurities having a large mass number to remove them, and energy can be given to a small mass ion and an ion in a necessary and sufficient range, thereby increasing the energy use efficiency. it can. This eliminates the need for a large power supply, which can reduce installation costs.

Further, in the chemical substance detection device according to the present invention, impurities are removed using a SW IFT waveform that does not give a voltage amplitude in a frequency band corresponding to a plurality of chemical substances to be detected. Then, multiple chemical substances to be detected were detected simultaneously by mass spectrometry. As described above, since a plurality of chemical substances to be detected are simultaneously detected, highly accurate measurement can be performed, and combustion control accuracy can be increased.

Further, in the chemical substance detecting apparatus according to the present invention, the chemical substance detecting apparatus may further have a larger ion ion potential than the chemical substance to be detected. An ion irradiation unit is provided which gives an energy smaller than the sum of the dissociation energy of the ion to the substance to the detection target substance and ionizes the detection target chemical substance. Further, in the chemical substance detecting apparatus according to the present invention, in the chemical substance detecting apparatus, the ionization means detects an energy higher than an ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential. It was given to target chemical substances. The chemical substance detection device according to these inventions detects an energy larger than the ionization potential of the chemical substance to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ion of the chemical substance to be detected. This was given to the target chemical substance, and the detection target chemical substance was ionized. For this reason, the detection sensitivity of the mass spectrometry means can be increased because unnecessary fragments are not generated and the remaining chemical substances to be detected need not be destroyed. Therefore, in combination with the action and effect exerted by the chemical substance detection device, the detection sensitivity of the mass spectrometer can be further improved, and highly accurate measurement can be performed.

Further, in the method for detecting a chemical substance according to the present invention, when the ionization is performed, An energy larger than the ionization potential of the chemical substance and smaller than the sum of the ionization potential of the chemical substance and the dissociation energy of the ions of the chemical substance to be detected is given to the chemical substance to be detected. Therefore, it can be ionized without destroying the chemical substance to be detected, and the generation of unnecessary fragments during ionization is extremely small. Therefore, it is not necessary to destroy remaining detection target chemical substances, and the detection sensitivity of the mass spectrometry method can be increased.

Further, in the method for detecting a chemical substance according to the present invention, a TICKLE waveform is given to the chemical substance to be detected to fragment the chemical substance to be detected. Therefore, even if there is an impurity in the frequency band corresponding to the mass number of the chemical substance to be detected, it is possible to measure accurately by eliminating this effect. As a result, almost all the fragments of the target chemical substance can be subjected to mass spectrometry, and the detection sensitivity of the analysis can be increased in the mass spectrometry process.

In the method for detecting a chemical substance according to the present invention, impurities present at a predetermined ratio or more are selectively removed. For this reason, necessary and sufficient impurities can be removed with less energy than in the case of removing all impurities. Also, less energy is required, so the power supply can be made smaller and more economical.

Further, in the method for detecting a chemical substance according to the present invention, the voltage amplitude of the SW IFT waveform at a frequency corresponding to an impurity giving a signal intensity higher than a predetermined signal intensity is increased, and the frequency of a portion where the impurity concentration is low is increased. The voltage amplitude was reduced. Therefore, particularly high-concentration impurities can be selectively removed, so that the energy required for removing low-concentration impurities can be reduced. This requires less energy to remove impurities, and is economical because it is not necessary to use a large power source unnecessarily.

Further, in the method for detecting a chemical substance according to the present invention, larger energy is given to an impurity having a large mass number than to an impurity having a small mass number. Further, in the method for detecting a chemical substance according to the present invention, when the frequency spectrum of the SW IFT waveform whose voltage amplitude increases as the frequency decreases becomes smaller, the voltage amplitude per mass number is converted when the mass number is plotted on the horizontal axis. Is almost constant Cried. As a result, sufficient energy is given to ions having a large mass number to remove the ions, and energy can be given to a small mass ion or ion in a necessary and sufficient range. Efficiency can be increased. This eliminates the need for a large power supply, which can reduce installation costs.

In the method of detecting a chemical substance according to the present invention, impurities are removed using a SWIFT waveform that does not give a voltage amplitude in a frequency band corresponding to a plurality of chemical substances to be detected. Then, multiple chemical substances to be detected were detected simultaneously by mass spectrometry. As described above, since a plurality of chemical substances to be detected are simultaneously detected, highly accurate measurement can be performed.

Further, in the method for detecting a chemical substance according to the present invention, the fragmentation is performed in order from the detection target substance having the smallest mass number among the plurality of detection target chemical substances. As a result, all of the multiple chemical substances to be detected can be detected, so that the sensitivity in mass spectrometry can be increased, and more accurate measurement can be performed.

Further, in the method for detecting a chemical substance according to the present invention, the method for detecting a chemical substance may include providing a TICKLE waveform including frequencies corresponding to at least two types of isotopes of the chemical substance to be detected, At least two of the chemical isotopes were fragmented for mass spectrometry. As described above, since a plurality of isotopes are used in mass spectrometry, detection accuracy can be improved even when only a trace amount of dioxins or their precursors is present in exhaust gas.

In the method for detecting a chemical substance according to the present invention, at least two of the isotopes of fragments generated from the chemical substance to be detected are subjected to mass spectrometry. As described above, since isotopes of a plurality of fragments are used in mass spectrometry, detection accuracy can be improved even when dioxins and their precursors are present only in trace amounts in exhaust gas.

Further, in the method for detecting a chemical substance according to the present invention, the method for detecting a chemical substance may further include, before the ion trapping step, an ionization potential that is larger than an ionization potential of the chemical substance to be detected. Object Energy smaller than the sum of the dissociation energies of the ions is given to the target chemical substance to ionize the target chemical substance. In the method for detecting a chemical substance according to the present invention, in the ionization step, energy higher than an ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential is applied to the chemical substance to be detected. did. For this reason, the detection sensitivity in mass spectrometry can be increased because unnecessary fragments are not generated and the target chemical substance to be left is not destroyed. Therefore, in addition to the action and effect exerted by the above-described method for detecting a chemical substance, the detection sensitivity of the mass spectrometer can be further improved, and highly accurate measurement can be performed. Industrial applicability

As described above, the chemical substance detection device and the chemical substance detection method of the present invention are useful for highly accurately detecting dioxins and their precursors contained in very small amounts in exhaust gas from refuse incineration facilities and the like. It is suitable for improving the detection speed of the target chemical substance to the extent that the combustion conditions can be controlled even while operating a heating furnace or other combustion furnace.

Claims

The scope of the claims

1. The energy is given to the chemical substance to be detected, which is larger than the ionization potential of the chemical substance to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ions of the chemical substance to be detected. Ionization means for ionizing the chemical substance to be detected;

An ion trap means for confining an ion group containing ions of the chemical substance to be detected ionized by the ionization means by an electric field, a magnetic field, or the like, and corresponding to an orbital resonance frequency of ions of the chemical substance to be detected Impurity removing means for applying energy to the group of ions by a SW IFT waveform including a frequency component excluding a frequency to remove impurities.

Mass spectrometry means for measuring the mass of the detection target chemical substance,

An apparatus for detecting a chemical substance, comprising: 2. An energy larger than the ionization potential of the target chemical substance and smaller than the sum of the ionization potential and the dissociation energy of the ions of the target chemical substance is given to the target chemical substance. Ionization means for ionizing a substance;

An ion trap means for confining an ion group containing ions of the detection target chemical substance ionized by the ionization means by an electric field, a magnetic field, or the like; and a frequency corresponding to an orbital resonance frequency of the ions of the detection target chemical substance. Impurity removing means for removing energy by applying energy to the ion group by a SWIFT waveform including the removed frequency component;

Fragmentation means for applying energy to the group of ions with a TICKLE waveform of a frequency component corresponding to the orbital resonance frequency of the ions of the chemical substance to be detected to fragment the ions of the chemical substance to be detected,

Mass spectrometry means for measuring the mass of the fragment of the detection target chemical substance, 2005/001465

Chemical substance detection device characterized by comprising 42,

3. The method according to claim 1 or 2, wherein the ionization means provides the detection target chemical substance with an energy higher than an ionization potential and not more than a value obtained by adding 4 eV to the ionization potential. The chemical substance detection device according to Item 2.

4. The chemical substance according to claim 1 or 2, wherein the ionizing means is a light generating means for generating light having a wavelength of 50 nm or more and 200 nm or less. Detection device.

5. The chemical substance detection device according to claim 1, wherein the ionization means is a vacuum ultraviolet light lamp.

6. An ion trap means for confining an ion group containing ions of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means;

At a frequency corresponding to the orbital resonance frequency of the impurity present at a concentration indicating a signal intensity higher than the predetermined signal intensity, the orbital resonance frequency of the impurity existing at a concentration indicating a signal intensity lower than the predetermined signal intensity is determined. Arbitrary waveform generating means for generating a SWIFT waveform having a voltage amplitude larger than the voltage amplitude in the corresponding frequency band, and the SWIFT waveform generated by the arbitrary waveform generating means, wherein the ions are trapped in the ion trap means. Mass spectrometry means for measuring the mass of the chemical substance to be detected or a fragment thereof after removing the impurities by applying the chemical substance to the chemical substance.

7. ion trap means for confining ions containing ions of the chemical to be detected ionized by an electric field, a magnetic field or other means;

Generates SW IFT waveform with reduced voltage amplitude as frequency increases Means for generating an arbitrary waveform,

Mass spectrometry means for measuring the mass of the chemical substance to be detected or this fragment after applying the SWIFT waveform to the ions confined in the ion trap means to remove the impurities,

An apparatus for detecting a chemical substance, comprising:

8. An ion trap means for confining a group of ions including ions of the chemical substance to be detected ionized by an electric field, a magnetic field or other means;

Arbitrary waveform generating means for generating a SWIFT waveform having a constant voltage amplitude distribution regardless of the mass number of molecules to be removed by SWIFT,

Mass analysis means for measuring the mass of the chemical substance to be detected or this fragment after applying the SWIFT waveform to the ion group confined in the ion trap means to remove the impurities,

An apparatus for detecting a chemical substance, comprising:

9. An ion trap means for confining an ion group including ions of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means;

An arbitrary waveform generating means for generating a SWIFT waveform that does not apply a voltage amplitude in a plurality of frequency bands corresponding to the mass numbers of a plurality of chemical substances to be detected and provides a voltage amplitude in a frequency band corresponding to the mass number of impurities; ,

Fragmentation means for energizing the ion group with a TICKLE waveform having a plurality of frequency components corresponding to the orbital resonance frequencies of the plurality of detection target chemicals to fragment the plurality of detection target chemicals; ,

Mass spectrometry means for measuring the mass of the chemical substance to be detected or the fragment after applying the SWIFT waveform to the ion group confined in the ion trap means to remove the impurities;

An apparatus for detecting a chemical substance, comprising:

10. Further, an energy that is larger than the ionization potential of the target chemical substance and smaller than the sum of the ionization potential and the dissociation energy of the ion of the target chemical substance is given to the chemical substance to be detected. 10. The chemical substance detection device according to claim 6, further comprising an ionization means for ionizing the detection target chemical substance.

11. The method according to claim 10, wherein the ionization means provides the detection target substance with energy higher than an ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential. An apparatus for detecting a chemical substance according to the above item.

1 2. The energy that is greater than the ionization potential of the chemical to be detected and less than the sum of the ionization potential and the dissociation energy of the ions of the chemical to be detected is given to the chemical to be detected. An ionization process for ionizing chemical substances;

An ion trapping step for confining an ion group including ions of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means;

An impurity removing step of applying energy to the ion group by a SWIFT waveform including a frequency component excluding a frequency corresponding to an orbital resonance frequency of the ions of the detection target chemical substance to remove impurities by applying an energy to the ion group;

Mass spectrometry step of measuring the mass of the detection target chemical substance,

A method for detecting a chemical substance, comprising:

1 3. The energy given to the target substance is larger than the ion potential of the target substance and smaller than the sum of the ionization potential and the dissociation energy of the ions of the target substance. An ionization step for ionizing the chemical substance to be detected; An ion trapping step for confining an ion group including ions of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means;

An impurity removal step of applying energy to the ion group by a SWIFT waveform including a frequency component excluding a frequency corresponding to an orbital resonance frequency of ions of the chemical substance to be detected to remove impurities.

A fragmentation step of energizing the ion group with a TICKLE waveform of a frequency component corresponding to the orbital resonance frequency of the ion of the chemical substance to be detected to fragment the ion of the chemical substance to be detected,

A mass spectrometry step of measuring the mass of a fragment of the chemical substance to be detected, and a method for detecting a chemical substance.

1 4. An ion trap process for confining an ion group including ions of the chemical substance to be detected ionized by an electric field, a magnetic field, or other means;

An impurity removal step of measuring a distribution of impurities contained in the ion group and applying a SWIFT waveform including a frequency component corresponding to an impurity present at a predetermined ratio or more to the ion group to remove the impurities;

A mass spectrometry step of measuring the mass of the detection target chemical substance or a fragment thereof;

A method for detecting a chemical substance, comprising:

.

15. An ion trapping step for confining ions containing ions of the chemical substance to be detected by an electric field, a magnetic field, or other means;

At a frequency corresponding to the orbital resonance frequency of the impurity present at a concentration indicating a signal intensity higher than the predetermined signal intensity, the orbital resonance frequency of the impurity existing at a concentration indicating a signal intensity lower than the predetermined signal intensity is determined. An impurity removing step of applying a SWIFT waveform having a voltage amplitude larger than the voltage amplitude in the corresponding frequency band to the ions to remove impurities; A mass spectrometry step of measuring the mass of the detection target chemical substance or a fragment thereof;

A method for detecting a chemical substance, comprising:

16. An ion trapping step of confining ions containing ions of the chemical substance to be detected by an electric field, a magnetic field, or other means;

An impurity removing step of applying a SW I F T waveform having a reduced voltage amplitude as the included frequency increases to the ion group to remove impurities,

A method for detecting a chemical substance, comprising:

1 7. An ion trap process for confining a group of ions including ions of the chemical to be detected, which is ionized by an electric field, a magnetic field, or other means;

An arbitrary waveform generation step of generating a SWIFT waveform having a constant voltage amplitude distribution regardless of the mass number of the molecule to be removed by SWIFT;

A mass spectrometry step of measuring the mass of the chemical substance to be detected or the fragment after applying the SW IFT waveform to the ions confined in the ion trap means to remove the impurities;

A method for detecting a chemical substance, comprising:

18. An ion trapping step for confining ions containing ions of the chemical substance to be detected by an electric field, a magnetic field, or other means;

In a plurality of frequency bands corresponding to the mass number of the plurality of substances to be detected, a SW IFT waveform that does not give a voltage amplitude is given to the group of ions to remove impurities and leave a plurality of detected chemical substances. Process and

Mass spectrometry step for measuring the mass of the chemical substance to be detected or its fragment When,

A method for detecting a chemical substance, comprising:

1 9. An ion trapping process for confining an ion group containing ions of a plurality of target chemical substances having different mass numbers by an electric field, a magnetic field, or other means; Applying a SW IFT waveform that does not provide a voltage amplitude to the group of ions in a plurality of corresponding frequency bands to remove impurities and leave a plurality of detection target chemical substances;

A fragmentation step of fragmenting in order from the detection target chemical substance having a smaller mass number among the plurality of detection target chemical substances;

A method for detecting a chemical substance, comprising:

20. An ion trapping process to confine a group of ions containing multiple ions of the target chemical substance with different mass numbers ionized by electric field, magnetic field, or other means, and to respond to the mass numbers of multiple target chemical substances. Applying a SW IFT waveform that does not provide a voltage amplitude to the ion group in a plurality of frequency bands to remove impurities and leave a plurality of detection target chemical substances;

Fragmentation by giving a TICKLE waveform containing frequencies corresponding to at least two types of isotopes of the target chemical substance and fragmenting at least two of the isotopes of the target chemical substance Process and

A method for detecting a chemical substance, comprising:

2 1. In the above mass spectrometry process, the flag generated from the chemical substance to be detected The method for detecting a chemical substance according to any one of claims 12 to 20, wherein at least two types of isotopes of the element are measured.

2 2. Furthermore, prior to the ion trapping step, an energy that is greater than the ionization potential of the chemical to be detected and smaller than the sum of the ionization potential and the dissociation energy of the ions of the chemical to be detected is set to The method for detecting a chemical substance according to any one of claims 14 to 20, further comprising an ionization step of giving the substance and ionizing the chemical substance to be detected.

23. The method according to claim 22, wherein in the ionization step, energy higher than the ionization potential and equal to or less than a value obtained by adding 4 eV to the ionization potential is given to the chemical substance to be detected. Method for detecting the described chemical substance.