CN203870077U - Secondary cold trap enrichment device and GC-FID (Gas Chromatography-Flame Ionization Detector) combined device for detecting trace phosphine - Google Patents
Secondary cold trap enrichment device and GC-FID (Gas Chromatography-Flame Ionization Detector) combined device for detecting trace phosphine Download PDFInfo
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Abstract
The utility model belongs to the technical field of phosphine detection and discloses a secondary cold trap enrichment device and GC-FID (Gas Chromatography-Flame Ionization Detector) combined device for detecting trace phosphine. In the secondary cold trap enrichment device and GC-FID combined device, a carrier gas system of a GC-FID analysis system is connected with a six-way valve of a secondary cold trap enrichment system, and an outlet of a secondary cold trap is connected with a gas phase sampler injector of the GC-FID analysis system through a capillary tube. The combined device has the benefits that carrier gas in the secondary cold trap enrichment system and the GC-FID analysis system is set and controlled by the carrier gas system of the GC-FID analysis system, the gas pressure and the gas flow rate are more accurate and more stable to control, and meanwhile, a good fit with the GC-FID analysis system can be realized, so that the reproducibility and the stability of the system are greatly improved.
Description
Technical field
The utility model belongs to hydrogen phosphide detection technique field, is specifically related to a kind of secondary cold-trap enrichment for detection of trace hydrogen phosphide and GC-FID combined apparatus.
Background technology
Hydrogen phosphide (PH
3) be a kind of important reduction-state form of P elements in physical environment, this viewpoint is generally accepted.Since the people such as Devai in 1988 detect first the existence of hydrogen phosphide in Sewage Plant volatile matter, increasing scientific research personnel has participated in the middle of the research of hydrogen phosphide association area.The research of hydrogen phosphide is not only had to important its significance for geochemistry for understanding P elements in occurring in nature circulation, simultaneously also for the solution of at present day by day serious body eutrophication problem provide a kind of new solution party to.
Hydrogen phosphide quantitatively and method for qualitative analysis mainly contain molybdenum blue colorimetric method and vapor-phase chromatography.The former complicated operation, length consuming time, the low mensuration that is not suitable for a large amount of samples and low concentration sample of sensitivity; The latter is convenient and swift, but sample pretreatment is complicated, and because hydrogen phosphide is easily subject to extraneous factor as the impact of light and oxygen etc., the standard method of analyzing it as hydrogen phosphide not yet at present.The principle that molybdenum blue spectrophotometric method is measured hydrogen phosphide is that other hydrogen phosphide are contacted with strong oxidizer, forms orthophosphate, then by spectrophotometer indirect detection, obtains the content of hydrogen phosphide.The method is because degree of accuracy is not high, disturbing factor how to be particularly only applicable to concentration higher occasion.
Content at Phosphine in Natural Environment is very low, adopts molybdenum blue colorimetric method method almost to can't detect, and this has also caused before vapor-phase chromatography occurs, the research to hydrogen phosphide in environmental area is started late.But through the development of many decades, the application of vapor-phase chromatography and constantly progressive, has driven the constantly perfect of hydrogen phosphide detection technique.
Utility model content
In order to solve the shortcoming and defect part of prior art, the purpose of this utility model is to provide the enrichment of a kind of secondary cold-trap and GC-FID combined apparatus.
The utility model object is achieved through the following technical solutions:
A kind of secondary cold-trap enrichment for detection of trace hydrogen phosphide and GC-FID combined apparatus, comprise cold-trap secondary enrichment system and GC-FID analytic system, described cold-trap secondary enrichment system is comprised of sample feeding device, six-way valve, cold-trap and secondary cold-trap, and in cold-trap and secondary cold-trap, set temperature is at thread detector; Described GC-FID analytic system is comprised of the carrier gas system of gas phase injector, chromatographic column, flame ionization detector (FID) and GC-FID analytic system, the interface of six-way valve connects respectively import and outlet, the import of secondary cold-trap and the carrier gas system of GC-FID analytic system of sample feeding device, a cold-trap, and the outlet of secondary cold-trap is connected to the gas phase injector of GC-FID analytic system by kapillary.
A described cold-trap or secondary cold-trap are comprised of enrichment capillary column and cold-trap cup, capillary column is placed in cold-trap cup, in cold-trap cup, pour liquid nitrogen into, cold-trap cup can be placed on lifting table, and regulate the distance between liquid nitrogen liquid level and capillary column in cold-trap cup to realize the constant of condenser temperature by lifting table, described enrichment capillary column preferred length is 100cm, and diameter is 0.53mm, interior filling Al
2o
3-Na
2sO
4capillary column (Kromat Corporation); Described temperature online detecting device control system is used Pt100 resistance and temperature analyzer.
The pretreating device of hydrogen phosphide enrichment can be set before the sample feeding device of described cold-trap secondary enrichment system, and described pretreating device is the drying tube (50mm * 4mm) of two series connection, and porous carrier NaOH particle dry agent is housed in drying tube.
The above-mentioned secondary cold-trap enrichment of a kind of use and GC-FID combined apparatus detect the method for trace hydrogen phosphide, concrete detecting step is: the carrier gas flux of being set and being controlled in gas circuit by the carrier gas system of GC-FID analytic system is 1.5mL/min, then hydrogen phosphide detects sample and enters six-way valve by sample feeding device, under carrier gas drives, enter a cold-trap and carry out an enrichment, after an enrichment, rotate six-way valve to corresponding position, the hydrogen phosphide of enrichment is detected to sample and carry out that pyrolysis is analysed and by six-way valve, enter secondary cold-trap under carrier gas drives carries out secondary enrichment, the temperature of cold-trap and secondary cold-trap is all controlled as-90 ℃, after secondary enrichment completes, carrying out pyrolysis analyses, detection sample after pyrolysis is analysed enters chromatographic column from the gas phase injector of GC-FID analytic system under carrier gas drives, under 90 ℃ of conditions of column temperature, carry out separation, finally enter flame ionization detector (FID) detects at 220 ℃.
By device tool of the present utility model, have the following advantages and beneficial effect:
(1) in pick-up unit of the present utility model, carrier gas is all set and is controlled by the carrier gas system of GC-FID analytic system, external carrier gas compared to existing technology, air pressure and gas flow rate are controlled more precise and stable, and can better coordinate with GC-FID analytic system, greatly improved reappearance and the stability of system;
(2) adopt device of the present utility model, can reduce the detection limit of hydrogen phosphide and increase substantially the precision that hydrogen phosphide detects;
(3) GC-FID analytic system of the present utility model adopts flame ionization detector (FID), there is the advantages such as simple in structure, easy to operate, price economy, simultaneously insensitive to gas flow rate, pressure, temperature variation again, reduced Environmental Trace hydrogen phosphide and detected operation easier and the financial cost of analyzing, for more researchists participate in the research of hydrogen phosphide in environment, provided convenience.
Accompanying drawing explanation
Fig. 1 is the agent structure schematic diagram of the enrichment of secondary cold-trap and GC-FID combined apparatus in the utility model embodiment 1.
In figure, mark is described as follows: 1-sample feeding device; 2-six-way valve; Cold-trap of 3-; Bis-cold-traps of 4-; 5-on-line temperature monitoring device; 6-gas phase injector; 7-chromatographic column; 8-flame ionization detector (FID); The carrier gas system of 9-GC-FID analytic system; 1.-6. represent 6 interfaces of six-way valve.
Embodiment
Below in conjunction with embodiment, the utility model is described in further detail, but embodiment of the present utility model is not limited to this.
Embodiment 1
As shown in Figure 1, a kind of secondary cold-trap enrichment for detection of trace hydrogen phosphide and the GC-FID combined apparatus of the present embodiment, comprise cold-trap secondary enrichment system and GC-FID analytic system, described cold-trap secondary enrichment system is comprised of sample feeding device 1, six-way valve 2, cold-trap 3 and secondary cold-trap 4, and in cold-trap and secondary cold-trap, set temperature is at thread detector 5; Described GC-FID analytic system is comprised of the carrier gas system 9 of gas phase injector 6, chromatographic column 7, flame ionization detector (FID) 8 and GC-FID analytic system, the interface mode of six-way valve is: at 1. number interface, connect sample feeding device, 2. number interface is Waste gas outlet, 3. the import of number interface connecting secondary cold-trap, 4. number interface connects the carrier gas system of GC-FID analytic system, 5. number interface connects the outlet of a cold-trap, 6. number interface connects the import of a cold-trap, and the outlet of secondary cold-trap is connected to the gas phase injector of GC-FID analytic system by kapillary.
The secondary cold-trap enrichment of the present embodiment and GC-FID combined apparatus are for detection of the method for trace hydrogen phosphide:
Gas detects sample and injects before six-way valve, the carrier gas flux of first setting in gas circuit by the carrier gas system of GC-FID analytic system is 1.5mL/min, gas detects sample and under carrier gas drives, enters one-level cold-trap after by sample feeding device and six-way valve, in one-level cold-trap, carry out an enrichment, after an enrichment, rotate six-way valve to corresponding position, sample pyrolysis after an enrichment is analysed and through six-way valve, enter and in secondary cold-trap, carry out the enrichment of secondary cold-trap under carrier gas drives, the temperature of cold-trap and secondary cold-trap is all controlled as-90 ℃, after secondary enrichment, trigger gas chromatography makes it in acquisition state, the gaseous sample after secondary enrichment is analysed in pyrolysis, under driving, carrier gas enters chromatographic column from the gas phase injector of GC-FID analytic system, under 90 ℃ of conditions of column temperature, carry out separation, finally enter flame ionization detector (FID) detects at 220 ℃.
Embodiment 2
A kind of secondary cold-trap enrichment for detection of trace hydrogen phosphide and the GC-FID combined apparatus of the present embodiment, comprise cold-trap secondary enrichment system and GC-FID analytic system, cold-trap secondary enrichment system is comprised of sample feeding device, six-way valve, cold-trap and secondary cold-trap, in cold-trap and secondary cold-trap, Pt100 resistance and temperature analyzer is set, cold-trap and secondary cold-trap are 100cm by length, diameter is 0.53mm, interior filling Al
2o
3-Na
2sO
4enrichment capillary column and cold-trap cup form, capillary column is placed in cold-trap cup, in cold-trap cup, pours liquid nitrogen into, cold-trap cup is placed on lifting table, and regulates the distance between liquid nitrogen liquid level and capillary column in cold-trap cup to realize the constant of condenser temperature by lifting table; GC-FID analytic system is comprised of the carrier gas system of gas phase injector, chromatographic column, flame ionization detector (FID) and GC-FID analytic system, the interface of six-way valve connects respectively sample feeding device, the import of secondary cold-trap, the carrier gas system of GC-FID analytic system, import and the outlet of a cold-trap, and the outlet of secondary cold-trap is connected to the gas phase injector of GC-FID analytic system by kapillary.The series connection drying tube that two specifications are 50mm * 4mm is also set before the sample feeding device of described combined apparatus, porous carrier NaOH particle dry agent (Merek KGaA, 64271Darmstadt, Germany) is housed in drying tube.
The secondary cold-trap enrichment of the present embodiment and GC-FID combined apparatus are for detection of the method for trace hydrogen phosphide, and concrete detecting step is:
(1) before test, prepare
First carry out the peripheral inspection of equipment, comprise hydrogen, high pure nitrogen and dry air that gaseous sample, liquid nitrogen and gas chromatography are used, check that the capacity of liquid nitrogen container and gas cylinder guarantees the unlikely interruption of use procedure, make regular check on its valve simultaneously and guarantee experiment safety.Start preheating, opens GC, downloads experimental arrangement method after igniting, and preheating 1～2h, observes and after GC baseline stability, can start to test sample.After baseline stability, prepare cold-trap, first liquid nitrogen is poured in cold-trap cup, cold-trap is placed on lifting table, slowly cold-trap is risen, kapillary is immersed in cold-trap, treat that temperature drops to subzero 90 ℃ and can start sample introduction.
(2) sample introduction and enrichment for the first time
Gas detects sample and injects before sample feeding device, and the drying tube that is first 50mm * 4mm through the specification of two series connection, is equipped with porous carrier NaOH particle (Merek KGaA, 64271Darmstadt, Germany), to remove CO in pipe
2, H
2o, H
2s gas.The carrier gas flux of controlling in gas circuit by the carrier gas system of GC-FID analytic system is 1.5mL/min, gas after filtration enters one-level cold-trap after by six-way valve under carrier gas drives, in the enrichment capillary column of one-level cold-trap, carry out enrichment (enrichment behavior comprised under cryogenic conditions, be adsorbed on capillary surface and reach boiling point after liquefy), enriching column is that a segment length is 100cm, diameter is 0.53mm, interior filling Al
2o
3-Na
2sO
4kapillary (Kromat Corporation), this enrichment is separated by the hydrogen phosphide gas lower with boiling points such as hydrocarbon, oxygen, nitrogen.From sample introduction, start timing, enrichment time 1min.
(3) secondary enrichment
After an enrichment, rotate six-way valve to corresponding position, the cold-trap cup of falling a cold-trap exposes enrichment capillary column, with warm braw, evenly purging enrichment capillary column surface makes its temperature rise to room temperature, be enriched in hydrogen phosphide in capillary column in intensification afterwards rapidly from capillary desorption and gasification, under carrier gas drives, through six-way valve, enter in the enrichment capillary column of secondary cold-trap and carry out the enrichment of secondary cold-trap, by the enrichment of secondary cold-trap, improve the accumulation rate of hydrogen phosphide, increase response signal value.From warm braw, purge and start timing, enrichment time 1min.
(4) enter gas chromatography
After secondary enrichment, trigger gas chromatography makes it in acquisition state, and the cold-trap cup of falling secondary cold-trap exposes enrichment capillary column, evenly purges enrichment capillary column surface make its temperature rise to room temperature with warm braw.Former be enriched in hydrogen phosphide in kapillary in intensification afterwards rapidly from capillary desorption and gasification, under carrier gas drives, from the gas phase injector of GC-FID analytic system, enter chromatographic column and carry out separation under 90 ℃ of column temperatures, finally enter flame ionization detector (FID) and detect at 220 ℃.Before measuring actual sample, need to test hydrogen phosphide standard correction sample, to determine the appearance time of hydrogen phosphide, make the typical curve that phosphine concentration detects simultaneously.When measuring actual sample, the sample peak value that gas chromatograph is recorded and typical curve are compared and are drawn sample concentration value.
By the checkout equipment of the present embodiment and method, to paddy rice in typical water rice field, In Guangzhou Area, the content of the rice soil combined hydrogen phosphide (MBP) when each growth period detects respectively, before detection, first rice soil is prepared into gas and detects sample, concrete preparation process is: gather fresh paddy rice pedotheque, 1g sample is put into digestion tube, utilize the H that 5mL concentration is 0.5mol/L
2sO
4solution carries out heating and decompose to it in digestion tube, with high pure nitrogen, takes out of and clears up the gas obtaining, and finally these gases (being the gas hydrogen phosphide that combined hydrogen phosphide discharges) is detected by this detection system.Testing result is as shown in table 1.
Table 1 rice soil combined hydrogen phosphide (MBP) content detection result
System repeatability and stability checking:
Experimental group: choosing phosphine concentration is 1.39ng/m
3standard model and the jointing stage sample in embodiment 2 adopt equipment and method in embodiment 2 to measure, sample size is 60ml, sample replication 4 times, analyzes the coefficient of variation of each sample, and result represents by the relative standard deviation (RSDs) of peak area.
Contrast groups: checkout equipment is that secondary cold-trap enrichment system is provided power and is not connected with the carrier gas system of GC-FID analytic system by external carrier gas with method and the difference of embodiment 2.
Experimental group and contrast groups result are as shown in table 2.
Table 2 experimental group and contrast groups system repeatability and stability the result
By table 2 result, can be found out, the relative standard deviation of experimental group sample peak area is 4.289% and 5.367%, the coefficient of variation obtaining is all at tolerance interval, illustrate that this method has good repeatability and stability, and compare with contrast groups, repeatability and the stability of the utility model device and method are better.
Detection limit checking:
To concentration, be 1.39ng/m
3hydrogen phosphide calibrating gas by the equipment of embodiment 2 and method, measure, sampling volume is 30mL, 60mL, 90mL, 120mL and 150mL, linear equation between hydrogen phosphide peak area and sampling volume is: y=579.773x-221.000, wherein x is hydrogen phosphide sampling volume (mL), y is peak area (pA), fitting coefficient (R Square)=0.9996, detects and is limited to 0.0417pg.
Above-described embodiment is preferably embodiment of the utility model; but embodiment of the present utility model is not restricted to the described embodiments; other any do not deviate from change, the modification done under Spirit Essence of the present utility model and principle, substitutes, combination, simplify; all should be equivalent substitute mode, within being included in protection domain of the present utility model.
Claims (4)
1. the secondary cold-trap enrichment for detection of trace hydrogen phosphide and GC-FID combined apparatus, comprise cold-trap secondary enrichment system and GC-FID analytic system, it is characterized in that: described cold-trap secondary enrichment system is comprised of sample feeding device, six-way valve, cold-trap and secondary cold-trap, in cold-trap and secondary cold-trap, set temperature is at thread detector; Described GC-FID analytic system is comprised of the carrier gas system of gas phase injector, chromatographic column, flame ionization detector and GC-FID analytic system, the interface of six-way valve connects respectively import and outlet, the import of secondary cold-trap and the carrier gas system of GC-FID analytic system of sample feeding device, a cold-trap, and the outlet of secondary cold-trap is connected to the gas phase injector of GC-FID analytic system by kapillary.
2. a kind of secondary cold-trap according to claim 1 enrichment and GC-FID combined apparatus, it is characterized in that: cold-trap or secondary cold-trap are comprised of enrichment capillary column and cold-trap cup, capillary column is placed in cold-trap cup, in cold-trap cup, pours liquid nitrogen into, and cold-trap cup is placed on lifting table.
3. a kind of secondary cold-trap according to claim 2 enrichment and GC-FID combined apparatus, is characterized in that: it is 100cm that described enrichment capillary column refers to long, and diameter is 0.53mm, interior filling Al
2o
3-Na
2sO
4enrichment capillary column.
4. a kind of secondary cold-trap according to claim 1 enrichment and GC-FID combined apparatus, is characterized in that: the drying tube of two series connection is set before the sample feeding device of described cold-trap secondary enrichment system, porous carrier NaOH particle dry agent is housed in drying tube.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104007196A (en) * | 2014-05-21 | 2014-08-27 | 华南理工大学 | Secondary cold trap enrichment and GC-FID (Gas Chromatography-Flame Ionization Detector) combining device and method for detecting trace hydrogen phosphide |
| CN106526015A (en) * | 2016-10-28 | 2017-03-22 | 中国南玻集团股份有限公司 | Apparatus for detecting trace phosphor impurity in hydrogen and detection method thereof |
| CN107643281A (en) * | 2017-09-29 | 2018-01-30 | 通标标准技术服务有限公司 | Industrial silicon dirt content test method |
| CN109030679A (en) * | 2018-07-19 | 2018-12-18 | 浙江赛鹭鑫仪器有限公司 | A kind of second level pyrolysis analysis system |
| CN109142575A (en) * | 2018-08-31 | 2019-01-04 | 四川永祥新能源有限公司 | The detection method of Phosphine content in a kind of production of polysilicon hydrogen |
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2014
- 2014-05-21 CN CN201420262648.1U patent/CN203870077U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104007196A (en) * | 2014-05-21 | 2014-08-27 | 华南理工大学 | Secondary cold trap enrichment and GC-FID (Gas Chromatography-Flame Ionization Detector) combining device and method for detecting trace hydrogen phosphide |
| CN106526015A (en) * | 2016-10-28 | 2017-03-22 | 中国南玻集团股份有限公司 | Apparatus for detecting trace phosphor impurity in hydrogen and detection method thereof |
| CN106526015B (en) * | 2016-10-28 | 2020-05-05 | 中国南玻集团股份有限公司 | Detection device and detection method for trace phosphorus impurities in hydrogen |
| CN107643281A (en) * | 2017-09-29 | 2018-01-30 | 通标标准技术服务有限公司 | Industrial silicon dirt content test method |
| CN109030679A (en) * | 2018-07-19 | 2018-12-18 | 浙江赛鹭鑫仪器有限公司 | A kind of second level pyrolysis analysis system |
| CN109142575A (en) * | 2018-08-31 | 2019-01-04 | 四川永祥新能源有限公司 | The detection method of Phosphine content in a kind of production of polysilicon hydrogen |
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| C14 | Grant of patent or utility model | ||
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Granted publication date: 20141008 Termination date: 20170521 |