KR20110046179A - Portable GCMS for Real-Time Volatile Organic Compounds Monitoring - Google Patents

Abstract

PURPOSE: A portable gas-chromatograph-mass-spectrometer(GCMS) for monitoring volatile organic compounds is provided to minimize contamination by rapidly verifying and responding contamination source. CONSTITUTION: A gas-chromatograph(GC) part(11) includes a sampling unit(22), a small-sized GC module(21), and nitrogen feed source(23) supplying the carrier gas of the GC module. A mass-spectrometer(SM) part(13) includes a vacuum chamber(31) and a quadrupled mass analyzer(34) installed in the vacuum chamber. In the vacuum chamber, vacuum is maintained. A GCMS interface(12) connects the GC part and the MS part.

Description

Portable GCMS for Real-Time Volatile Organic Compounds Monitoring

The present invention relates to a portable gas chromatograph-mass spectrometer capable of qualitatively and quantitatively analyzing volatile organic compounds in the atmosphere up to a trace amount in real time. The present invention relates to a portable gas chromatograph-mass spectrometer with light weight and minimal consumables.

In general, Gas Chromatograph-Mass Spectrometer (hereinafter, referred to as 'GCMS') is a technique for separating and analyzing components that can be vaporized over time. Like the GCMS, the portable GCMS has a gas chromatograph and a mass spectrometer.

U.S. Patent No. 5,426,300 (Portable GCMS System Using Getter Pump) consists of a vacuum chamber with a gas chromatograph and a membrane interface, which is a device for portable analysis and service modules with a getter pump and a mass spectrometer. Started. In order to maintain the high vacuum of the vacuum chamber, the ion getter pump was used as the auxiliary pump of the non-evaporable getter pump and the getter pump used in the chamber.The service module is a module for forming the initial high vacuum of the portable analysis module. High vacuum pumps such as diffusion pumps are also included. Since the non-evaporable getter pump used to maintain high vacuum in the vacuum chamber of the portable analysis module has no exhaust capacity for the inert gas, the ion getter pump should be used as an auxiliary pump to remove residual inert gas from the portable analysis module. In addition, when the non-evaporable getter pump is used for a certain period of time, the pumping speed becomes worse due to the adsorption of residues in the vacuum chamber of the getter material, and the life of the high vacuum maintenance pump ends. Therefore, it is very consumable, expensive as consumables, and a service module is required separately to make a high vacuum at every replacement. Although it is a portable analysis equipment, a service module that is only a portable analysis equipment becomes a mandatory option, and each time you go out to the field, you have to reach the high vacuum state with a service module and then go out. .

In addition, in the conventional US Patent No. 5,525,799 (Portable Gas Chromatograph Mass Spectrometer), the GCMS is put in a suitcase more easily than a conventional portable GCMS, but a vacuum system using an ion / sorption pump in a vacuum chamber including a mass spectrometer It has the limitations described above.

US Patent No. 6,351,983 (Portable Gas Chromatograph Mass Spectrometer for On-site Chemical Analyses) discloses a portable GCMS with a basic configuration of a laboratory-based GCMS, weighing ˜25 kg. The gas chromatograph unit is divided into a GC column and an injection unit again. The injection is performed using a micro syringe, and the sample is vaporized by heating and injected into the mass spectrometer through the column. A diaphragm pump is used as a turbo pump and an auxiliary pump for the high vacuum of the vacuum chamber including the mass spectrometer. An ionization pump is configured to maintain the vacuum when the sample is not analyzed. The LED display panel is mounted on the unit to show the operation status of vacuum pumps, heaters, valves, etc., and the laptop is connected to perform tuning, heaters, pumps, fans, data collection, and search. It is difficult to analyze the volatile organic compound in real time in the configuration of the sample injecting unit which needs to inject the sample into the microsilage through the separate sample collection.

 In the above-described conventional technology, the mass filter portion of the mass spectrometer is used as a quadrupole, while in US Patent No. 5,515,061 (Miniaturized Chromatograph Mass Spectrometer System), the mass spectrometer is used as a magnetic sector analyzer. The module presented an integrated GCMS in the thermal zone. Turbo pumps and mechanical pumps were used to maintain the vacuum in the vacuum chamber including the magnetic sector analyzer, and various sample injection methods including the concentrator were proposed by improving the existing GCMS, but only 2-way or 3-way valves were used. Injecting into gas chromatograph or mass spectrometer because it is composed of a conduit, and especially, it is injected in a single direction regardless of the molecular weight of all volatile organic compounds injected during sample injection using the concentration device and discharged from the concentration device in the injected direction. No injection focusing of the sample is done. In addition, since the GC column is in the oven, there is a limit in power consumption and miniaturization.

Therefore, in order to qualitatively and quantitatively analyze volatile organic compounds in the air in real time in the field, it is required to develop a compact and lightweight portable GCMS that is not only sufficient performance, but also durable, convenient, and easy to maintain and maintain. .

Accordingly, an object of the present invention is to provide a field-applicable portable GCMS for qualitatively and quantitatively analyzing trace amounts of volatile organic compounds in the field in real time while solving the above problems.

Portable GCMS for real-time monitoring of volatile organic compounds according to the present invention

A gas chromatograph (GC) including a sampling device into which a volatile organic compound is injected, a small gas chromatograph module, and a nitrogen source for supplying a carrier gas of the gas chromatograph module;

A mass spectrometer (MS) including a vacuum chamber in which a vacuum is maintained by a vacuum system and a quadrupole mass spectrometer included in the vacuum chamber;

A GCMS interface connecting the GC unit and the MS unit; Is configured integrally.

On the other hand, the sampling device is characterized in that it comprises an atmospheric sample concentrator comprising an adsorbent consisting of carbon nanotube-metal nanocomposite.

In this case, it is preferable that the sampling device includes a sampling loop or an atmospheric sample concentrator which can be replaced and inserted, and the sampling device preferably includes a switching valve for converting a pipeline as a pseudo switching device.

On the other hand, the vacuum system preferably comprises a small turbopump and a small diaphragm pump.

On the other hand, the nitrogen source can be recharged portable and the small gas chromatograph module is removable.

The portable GCMS for real-time monitoring of volatile organic compounds according to the present invention has a power supply system using a secondary battery or wired / wireless data transmission and reception with internal and external, and any one or more of a small computer for analyzing data of the GC unit and the MS unit. This may be further included integrally.

As described above, the portable GCMS for real-time monitoring of volatile organic compounds according to the present invention can detect, classify and monitor volatile organic compounds in the field up to the extremely low concentration range.

Therefore, the environmental improvement effect is to know in detail the generation or emission information of pollutants through real-time on-site measurement of harmful substances in the air, thereby minimizing the pollution level by identifying the source of pollutant sources and responding quickly, and fostering the future as a backbone industry. Real-time monitoring of pollutants in micro-hazardous gases and semiconductor manufacturing equipment in advanced industries such as semiconductor-related industries, as well as in the analysis of biomaterials and in the medical industry, in the detection of military chemicals and biological materials, This equipment can detect and check the smuggling of prohibited drugs and can be used very effectively in airports and harbors.

Hereinafter, the portable GCMS 10 for real-time volatile organic compound monitoring as described above will be described in detail with reference to the accompanying drawings. In describing the present invention, when it is determined that a detailed description of a related known function or known configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. And certain features shown in the drawings are enlarged or reduced or simplified for ease of description, the drawings and their components are not necessarily drawn to scale. However, those skilled in the art will readily understand these details.

The portable GCMS 10 for real time volatile organic compound monitoring of the present invention will be apparent from the description below.

1 is a block diagram of a portable GCMS 10 for real-time volatile organic compound monitoring according to the present invention, Figure 2 is a plan view schematically showing a portable GCMS 10 for real-time volatile organic compound monitoring according to the present invention. .

The portable GCMS 10 for real-time monitoring of volatile organic compounds according to the present invention

A gas chromatograph (11) including a sampling device (22) into which a volatile organic compound is injected, a small gas chromatograph module (21), and a nitrogen source (23) for supplying a carrier gas of the gas chromatograph module; A mass spectrometer (13) comprising a vacuum chamber (31) in which a vacuum is maintained by the vacuum system (32) and a quadrupole mass spectrometer (34) included in the vacuum chamber (31); A GCMS interface 12 connecting the GC 11 and the MS 13; A self power supply system 40 using a secondary battery; And a wired / wireless data transmission / reception with the inside and outside, and includes a small computer 53 for analyzing the data of the GC unit 11 and the MS unit 13 integrally.

The sampling device 22 includes a sampling loop and / or an atmospheric sample concentrator that can be inserted and replaced in a configuration in which the volatile organic compound is injected, so that the concentration and characteristics of the desired volatile organic compound can be changed. Therefore, selective sampling is possible. In addition, it is characterized in that it is controlled by using a switching valve for switching the pipeline as a similar opening and closing control device.

At this time, the atmospheric sample concentrator (preconcentrator) of the sampling device 22 includes a carbon nanotube-metal nanocomposite, so as to apply a carbon nanotube-metal nanocomposite to the direct sampling of volatile organic compounds in the air in the field and At the same time, it is desirable to have a high concentration effect. Carbon nanotube-metal nanocomposite used as the adsorbent is US Patent No. 7,217,311 (Method of Producing Metal Nanocomposite Powder Reinforced with Carbon Nanotubes and the Powder Prepared Thereby) and Korea Patent Publication 10-2005-0012556 Reinforced metal nanocomposite powder and a method for preparing the same) can be used.

The nitrogen source 23 is 100-150 psi of nitrogen to the portable canister in which nitrogen is supplied as a carrier gas of the volatile organic compound injected through the sampling loop or the atmospheric sample concentrator of the small gas chromatograph module 21. It is designed to be installed by charging it, and it can be used as a rechargeable through the carrier gas cartridge to prevent the carrier gas, which is frequently used during the operation of the equipment, from being consumable in the field. In addition, when high purity nitrogen can be supplied indoors rather than outdoors, high purity nitrogen may be directly supplied.

The volatile organic compound injected through the sampling loop or the atmospheric sample concentrator of the sampling device 22 passes through the small gas chromatograph module 21. The small gas chromatograph module 21 carries most of the existing gas chromatograph. By removing the oven of the occupied column, winding and heating the capillary column and the heating wire to increase the temperature of the capillary column uniformly and modularizing, greatly reducing the volume while maintaining the separation capacity of the capillary column, the temperature sensor in the center of the column module Inserted to accurately measure the temperature of the small gas chromatograph module 21, the fan for cooling the small gas chromatograph module 21 is mounted together. Since the use of the capillary column varies depending on the long-term use of the capillary column or the characteristics of the volatile organic compounds of the material to be analyzed, the small gas chromatograph module 21 itself is a separate real-time method of the present invention. It can be separated from the portable GCMS 10 for monitoring volatile organic compounds.

 Gas Chromatograph (GC) including the sampling device 22, the small gas chromatograph module 21, the nitrogen source 23 and the small diaphragm pump 32b for sampling and a flow control device (not shown). (11) The machine is 150 × 150 × 100 mm, the weight is 3 kg or less, the temperature control of the small gas chromatograph module 21, the temperature control of the fan, heater, and sampling device 22, the switching valve for switching the pipe and 2-way and 3-way valves, small diaphragm pump 32b for field sampling of volatile organic compounds in the air, and heater operation to prevent condensation in the conduit until volatile organic compounds are injected into the mass spectrometer 34 The back GC unit 11 is automatically controlled by the GC unit control device 51.

The GCMS interface 12 connecting the MS 13 and the GC 11, which will be described later, may include a PDMS between a small gas chromatograph module 21 at atmospheric pressure and a vacuum chamber 31 having a high vacuum of 10 ^-6 torr. The high vacuum of the vacuum chamber 31 was maintained by using a semi-permeable membrane made of Polydimethylsiloxane), and the semi-permeable membrane was volatile in the field in real time because the semi-permeable membrane had a concentration effect of 100 times or more volatile organic compounds during the sample introduction process of the small quadrupole mass spectrometer 34. The detection limit of the organic compound was lowered to allow measurement to a trace concentration.

The vacuum chamber 31 includes the mass spectrometer 34, and volatile organic compounds injected into the sample introduction portion of the quadrupole mass spectrometer 34 through the GCMS interface 12 are stored in the vacuum chamber 31. Ionized by the electron impact, the generated ions pass through the quadrupole filter to measure the ions according to each mass to obtain information on the molecular weight and structure of the volatile organic compound.

The vacuum system 32 uses a small diaphragm pump 32b as an auxiliary pump of the small turbo pump 32a and the small turbo pump 32a to maintain the high vacuum of the vacuum chamber 31, which must always maintain a high vacuum. use. The vacuum system 32 is integral with the portable GCMS 10 for real time volatile organic compound monitoring of the present invention. Therefore, the mass spectrometer 34 has a size of 190 x 360 x 120 mm in the vacuum chamber 31 including the mass spectrometer 34, and the total weight including the vacuum system 32 is about 6.0 kg. The turbopump used in the vacuum system 32 is simpler, faster, and more resistant to contamination than other high vacuum pumps. It is easy to maintain and there is no risk of contamination of the medium. Instead, there is some vibration, but if the problem is a vibration isolator can be installed to some extent. In addition, a mechanical pump is required when using a turbo pump, in which a small diaphragm pump 32b is used, and the diaphragm pump is used for a field requiring suction, transportation, and compression of air, neutral gas, and some corrosive gas. Small and easy to move The introduction of the small turbopump 32a and the small diaphragm pump 32b into the vacuum system 32 has taken into account the economics of the weight reduction of the equipment and the cost of consumables for maintenance and repair by the consumable pump.

The control system of the present invention is largely composed of the GC unit control unit 51 and the MS unit control unit 52. As described above, the GC unit control unit 51 is a GCMS interface (from the real-time sampling of volatile organic compounds). 12), the control of the operation of the quadrupole mass spectrometer 34, including the vacuum system 32 is automatically controlled through the MS control unit 52.

The above-described small computer 53 is mounted on the main body for convenient and easy real-time control and analysis. The data transmission system between the GC control unit 51 and the MS control unit 52 is RS 422, and the GC control unit 51 exchanges all data with the small computer 53 through the MS control unit. . The MS control device controls the equipment or collects data from the equipment through USB communication with the small computer 53 mounted thereon. Therefore, the 271 × 205 × 27 mm mounted on the main body of the present invention, the touch screen-type small computer 53 based on windows XP with a weight of 1.25 kg, the user in the field including the software for driving the equipment and analysis software Can analyze in real time and create files.

The self power supply system 40 is used for field analysis as a power source for the operation of the configuration. Any used rechargeable battery may be used. However, in the present invention, a lithium polymer battery having a size of 200 × 52 × 45 mm and a weight of 1.7 kg is configured in six series in which a voltage per cell is 3.7 Volt. At the state of 22.2 Volt, 10600 mAh, the portable GCMS 10 was able to be driven using a battery for more than 2 hours in real time in the field.

The present invention is a portable GCMS (10) for real-time monitoring of volatile organic compounds in the field to reduce the small size, light weight and the generation of consumables as much as possible, and to be portable, so as to facilitate rapid field movement and quantitative and qualitative analysis.

1 is a block diagram of a portable GCMS for real-time volatile organic compound monitoring according to the present invention.

2 is a plan view of a portable GCMS for real-time volatile organic compound monitoring according to the present invention.

**** Explanation of symbols for the main parts of the drawing ****

10: portable GCMS 11: GC part

12: GCMS interface 13: MS unit

21: small gas chromatograph module 22: sampling device

23: nitrogen source

31: vacuum chamber 32: vacuum system

32a: small turbopump 32b: small diaphragm pump

33: vacuum gauge 34: mass spectrometer

40: Scion Power Supply System

51: GC unit control unit 52: MS unit control unit

53: small computer

Claims (7)

A gas chromatograph (11) including a sampling device (22) into which a volatile organic compound is injected, a small gas chromatograph module (21), and a nitrogen source (23) for supplying a carrier gas of the gas chromatograph module; Wow The vacuum chamber 31 and the vacuum chamber 31 in which the vacuum is maintained by the vacuum system 32 which is subjected to the primary vacuum by the small diaphragm pump 32b and forms a high vacuum by the small turbo pump 32a connected thereto. An MS section including a quadrupole mass spectrometer 34 included in the mass spectrometer 13; And A GCMS interface 12 connecting the GC 11 and the MS 13; Portable GCMS (10) for real-time volatile organic compound monitoring is integrally formed. The method of claim 1, The sampling device (22) is a portable GCMS (10) for real-time volatile organic compound monitoring, characterized in that it comprises an atmospheric sample concentrator comprising an adsorbent consisting of carbon nanotube-metal nanocomposite. The method of claim 1, The sampling device (22) is portable GCMS (10) for real-time monitoring of volatile organic compounds, characterized in that it comprises a replaceable sampling loop or atmospheric sample concentrator. The method of claim 1, The sampling device (22) is a portable GCMS (10) for real-time monitoring of volatile organic compounds, characterized in that it comprises a switching valve for switching the pipeline as a pseudo switchgear. The method of claim 1, One or more of the power supply system 40 using a secondary battery or a small computer 53 capable of transmitting and receiving data to and from the inside and outside, and analyzing the data of the GC unit 11 and the MS unit 13 Portable GCMS (10) for real-time monitoring of volatile organic compounds, characterized in that further included. The method of claim 1, The nitrogen source (23) is portable GCMS (10) for real-time volatile organic compound monitoring, characterized in that the portable rechargeable. The method of claim 1, The small gas chromatograph module 21 is portable GCMS for real-time volatile organic compound monitoring, characterized in that the removable.

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