CN102539219B - A kind of method of purifying dioxin-like chemicals in environmental matrix extraction liquid - Google Patents
A kind of method of purifying dioxin-like chemicals in environmental matrix extraction liquid Download PDFInfo
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- CN102539219B CN102539219B CN201110396419.XA CN201110396419A CN102539219B CN 102539219 B CN102539219 B CN 102539219B CN 201110396419 A CN201110396419 A CN 201110396419A CN 102539219 B CN102539219 B CN 102539219B
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Abstract
The invention discloses a kind of method of purifying dioxin-like chemicals in environmental matrix extraction liquid, it comprises following compound adhesive column purification and Fu Luoli magnesium silicate-alkali alumina combined column purifies two purifying step, filler in compound adhesive post by lower and on be followed successively by glass wool, silica sand, neutral silica gel, alkaline silica gel, neutral silica gel, acidic silica gel, anhydrous sodium sulfate, the filler in Fu Luoli magnesium silicate-alkali alumina combined column by lower and on be followed successively by silanized glass cotton, silica sand, Fu Luoli magnesium silicate, alkali alumina, anhydrous sodium sulfate.Purification process of the present invention is brief, purifying step simple, can shorten to the time of purification process, improves purification efficiency, reduces purifying solvent use amount, saves cost, can promote carrying out fast of dioxin testing.
Description
Technical field
The present invention relates to technical field of environmental detection, be specifically related to a kind of method of purifying dioxin-like chemicals in environmental matrix extraction liquid.
Background technology
Dioxin, also known as dioxa glutinous rehmannia, is a kind of colorless and odorless, liposoluble substance that toxicity is serious, serious to harm.Dioxin is actually dioxin one abbreviation, what it referred to is not a kind of one matter, but the two large class organic compounds comprising numerous congener or isomeride that structures and characteristics is all very similar, namely polychlorinated dibenzo-2 dislikes English (PCDDs) and polychlorinated dibenzo (PCDFs).
In environment, the analysis of dioxin belongs to ultratrace, multicomponent analysis, and matrix effect is complicated, and qualitative and quantitative detection is complicated, and complete purification process is key link for organic micro-pollutant detects.At present in the development of purification process, mainly for the selection of filler and robotization and systematized improvement.At present, the purification method carried out has the five step methods of purification promoted in International Standards Method, national standard method and industry, wherein, five conventional step purification methods are thorough to sample purification, flow process simple, can the content of Accurate Determining dioxin and polychlorinated biphenyl, for environmental evaluation, risk assessment and research pollutant sources return contracting etc. to provide reliable experimental technique guarantee.The method comprises acidic silica gel column purification, the purification of multistage silicagel column, gel permeation chromatographic column purification, alkali alumina column purification Fu Luoli magnesium silicate column purification five purifying step, but there is following shortcoming: whole purification process is long, step is more loaded down with trivial details, the time needed is longer, purification method is complicated, high to the requirement of analyst, higher to the requirement of laboratory condition.Above problem limits carrying out fast of dioxin testing.
Summary of the invention
The object of the present invention is to provide a kind of method of purifying dioxin-like chemicals in environmental matrix extraction liquid, the method is quick, stable, simple and easy, cheap, can be widely used in common organic analysis laboratory, promotes carrying out fast of dioxin testing.
For achieving the above object, the present invention adopts following technical scheme:
A method for purifying dioxin-like chemicals in environmental matrix extraction liquid, is characterized in that comprising following purifying step:
1) compound adhesive column purification: the filler in described compound adhesive post by lower and on be followed successively by glass wool, silica sand, neutral silica gel, alkaline silica gel, neutral silica gel, acidic silica gel, anhydrous sodium sulfate, after environmental matrices extraction drop enters this compound adhesive post, use hexane.This step object is by the disposable removal of most interference matrix in sample, comprises grease, fatty acid, pigment, multiring aromatic hydrocarbon substance and various polar materials etc.
2) purification of Fu Luoli magnesium silicate-alkali alumina combined column: the filler in described Fu Luoli magnesium silicate-alkali alumina combined column by lower and on be followed successively by silanized glass cotton, silica sand, Fu Luoli magnesium silicate, alkali alumina, anhydrous sodium sulfate, by step 1) environmental matrices extraction after purification is after drop enters this Fu Luoli magnesium silicate-alkali alumina combined column, first use normal hexane/methylene chloride mixed liquor wash-out, wash-out must contain the sample solution of PCBs and other components, this part solution is discarded, the sample solution containing PCDD/Fs is obtained again with eluent methylene chloride.This step object is to remove organo-chlorine pesticide, low pole material, and separating most polychlorinated biphenyl (PCBs) and PBDE (PBDEs) etc., finally reaches the object of purification of target thing PCDD/Fs.Fu Luoli magnesium silicate is a kind of silicon alkaline soil material used at U.S. Register, and it and alkali alumina have similar purification function, optionally can remove organo-chlorine pesticide and low pole material.In addition, had experiment to prove, it has good effect to separation PCDD/Fs and PCBs.The chemical property of PCBs with PCDD/Fs is similar, and its chromatographic behavior is also similar.If be not separated in pre-treatment flow process and just carry out instrumental analysis, some compound will occur causing the phenomenon of overflowing altogether mutual interference, have impact on the Accurate Determining of PCDD/Fs.Therefore, must by two groups of compound separation in pre-treatment.
Preferably, step 2) in the normal hexane of normal hexane/methylene chloride mixed liquor and the volume ratio of methylene chloride be 95: 5.
Preferably, compound adhesive post selection blade diameter length ratio is the normal pressure pressure glass chromatography column of 1: 5 ~ 10, lower bands tetrafluoro section door.The sulfurization of what this compound adhesive post played a major role is sulfuric acid, therefore acidic silica gel is placed in upper strata, first remove most matrix effect, contribute to the clean-up effect of lower post chromatography.And between alkaline silica gel, add one deck neutral silica gel pad every, affect clean-up effect to avoid the neutralization reaction of alkaline silica gel.
Preferably, step 1) in, the internal diameter 2.5cm of compound adhesive post, column length 25cm, glass wool filler height 1cm, quartz sand filler height 1cm, neutral silica gel 3g, alkaline silica gel 4g, neutral silica gel 3g, acidic silica gel 40g, anhydrous sodium sulfate height 1cm.
Preferably, step 1) and step 2) filler before use through following process:
Neutral silica gel: be placed in exsiccator with muffle furnace 550 DEG C activation > 12h and save backup;
Alkali alumina: activate 8 hours with 500 DEG C of muffle furnaces, be placed in exsiccator and be down to room temperature, sealing is preserved, and uses in 72 hours;
Fu Luoli magnesium silicate: 140 DEG C of activation more than 24h, taking-up is placed in exsiccator and is down to room temperature interior use half an hour;
Anhydrous sodium sulfate: 450 DEG C of more than roasting 4h, are cooled to room temperature, is contained in be placed in exsiccator in port grinding bottle and saves backup;
Cotton and the silica sand of silanized glass: 450 DEG C of roastings more than 4 hours are for subsequent use;
Cotton and filter paper: with after methylene chloride ultrasonic half an hour three times, after vacuum drains solvent, be placed in exsiccator and save backup.
Preferably, the blade diameter length ratio of Fu Luoli magnesium silicate-alkali alumina combined column is 1: 5 ~ 10.
Preferably, step 2) in silanized glass cotton packing height 1cm, quartz sand filler height 1cm, Fu Luoli magnesium silicate 1g, alkali alumina 1g, anhydrous sodium sulfate height 1cm.
First to infiltrate by normal hexane pre-flush after compound adhesive column packing, first infiltrate by normal hexane pre-flush after Fu Luoli magnesium silicate-alkali alumina combined column filler.
Compared with prior art, the beneficial effect that the present invention produces is: the time that can shorten to purification process guaranteeing clean-up effect while, improves purification efficiency and improves, reduce purifying solvent use amount, save cost.
Accompanying drawing explanation
Fig. 1 is the structural representation of compound adhesive post of the present invention;
Fig. 2 is the structural representation of Fu Luoli of the present invention magnesium silicate-alkali alumina combined column.
Embodiment
Below in conjunction with specific embodiment, the present invention is described in further detail.
Embodiment 1
1) preparation of reagent is purified
1. neutral silica gel: 70 ~ 230 orders, purchased from Merk company (Darmstadt, Germany), is placed in exsiccator with muffle furnace 550 DEG C activation > 12h before using and saves backup;
2. acidic silica gel (40%H
2sO
4): in flask, take 60g activated silica gel, add the 40g concentrated sulphuric acid, vibration of jumping a queue is to silica gel uniformly flow state; The concentrated sulphuric acid (top grade is pure) is purchased from Guangzhou Chemical Reagent Factory;
3. alkaline silica gel (1.2%): add the sodium hydroxide solution that 30g concentration is 1mol/L in 100g activated silica gel, shake up, for subsequent use; Solid sodium hydroxide is purchased from Guangzhou Chemical Reagent Factory;
4. alkali alumina: high-purity alkali alumina, all activates 8 hours with 500 DEG C of muffle furnaces before using, is placed in exsiccator and is down to room temperature, and sealing is preserved, and uses in 72 hours;
5. Fu Luoli magnesium silicate: 60 ~ 100 orders, uses front 140 DEG C of activation more than 24h, and taking-up is placed in exsiccator and is down to room temperature interior use half an hour;
6. anhydrous sodium sulfate: top grade is pure, for 450 DEG C of more than roasting 4h before using, is cooled to room temperature, is contained in be placed in exsiccator in port grinding bottle to save backup.
7. the cotton and silica sand of silanized glass, 450 DEG C of roastings more than 4 hours are for subsequent use;
8. cotton and filter paper, with after methylene chloride ultrasonic half an hour three times, after vacuum drains solvent, is placed in exsiccator and saves backup.
2) preparation of compound adhesive post
Select internal diameter 2.5cm, the normal pressure pressure glass chromatography column of column length 25cm lower bands tetrafluoro section door, by lower and on insert the high glass wool filler of 1cm, quartz sand filler, 3g neutral silica gel, 4g alkaline silica gel, 3g neutral silica gel, 40g acidic silica gel, anhydrous sodium sulfate height 1cm that 1cm is high successively, as shown in Figure 1.Fill in rear 80ml normal hexane pre-flush and infiltrate glue post.
3) Fu Luoli magnesium silicate-alkali alumina combined column preparation
Select internal diameter 2.5cm, the normal pressure pressure glass chromatography column of column length 25cm lower bands tetrafluoro section door, by lower and on insert 1cm height silanized glass cotton, 1cm height silica sand, 3g neutral silica gel, 4g alkaline silica gel, 3g neutral silica gel, 40g acidic silica gel, anhydrous sodium sulfate height 1cm successively, as shown in the figure.Fill in rear 25ml normal hexane pre-flush and infiltrate glue post.
4) environmental matrices is extracted drop and enter compound adhesive post, with the normal hexane 120ml drip washing compound adhesive post of low polarity, and recovery sample solution.
5) step 4 is got) sample solution that obtains drips into Fu Luoli magnesium silicate-alkali alumina combined column, first obtain the sample solution containing PCBs and other components with normal hexane/eluent methylene chloride that 25ml volume ratio is 95: 5, a little sample segment solution is discarded, then obtains the sample solution containing pure PCDD/Fs with 50ml eluent methylene chloride.
Embodiment 2 method of the present invention and existing five contrasts of step purification method on solvent and time consumption
Prepare 12 identical environmental matrices extract samples, 6 samples adopt existing method to purify, namely acidic silica gel column purification, the purification of multistage silicagel column, gel permeation chromatographic column purification, alkali alumina column purification Fu Luoli magnesium silicate column purification five step purification process is carried out successively, record purifies the quantity of solvent and clarification time that use, results averaged, as shown in table 1; 6 samples adopt method of the present invention to purify, and record purifies the quantity of solvent and clarification time that use, and results averaged is as shown in table 1; Height explanation gas chromatography/high-resolution double focussing mass spectrometer combined instrument that the model finally using Waters, US to produce is HP6890N GC/Autospec Premierr uses Isotopic Internal Standard to determine the concentrated by rotary evaporation liquid of method to 12 samples after purification and detects, and the value of the FCDD/Fs in 12 samples is basically identical.
The existing five step methods of purification of table 1 and the contrast of the inventive method on solvent and time consumption
Contrasted from table 1, the clarification time can be reduced to 9 hours by 24 hours by method of the present invention, and purification efficiency improves more than 60%, and two kinds of purifying solvent use amounts decrease 458ml and 122ml respectively, save 66% and 71% respectively.
Embodiment 3 method of the present invention is applied in the result of actual sample extract
Use this optimization method, purifying is carried out to the PCDD/Fs in environmental matrices (comprising soil, sediment) extract, after final concentrate adds the interior mark of sample introduction, high-resolution gas chromatography/high-resolution double focusing magnetic GC-MS (HRGC/HRMS) is used to carry out instrumental analysis, instrument manufacturer facility man is Waters, US, and model is " HP6890N GC/Autospec Premier ".The instrument analytical method adopted is Isotopic Internal Standard sizing technique.The analysis result of all samples all meets the quality control and quality assurance that national and foreign standards requires.(1) quality control standard substance.
QCS or SRM, refers to the sample comprising concentration known all or part target compound, performs usefulness (US EPA, 1994) for checking experiment room.In adopting method of the present invention to detect batch two, QCS (EDF-5184, the sediment) extract that adds purifies, and the purification concentrate obtained carries out instrumental analysis, the analytical instrument of use.The experimental result of different batches is in table 2: twice experimental result of this method test stone reference substance is substantially identical compared with standard value, except 234678-HxCDF, all within the deviation range of reference value, and the target recovery, at 46-93%, demonstrates the good reproduction of this method in the extraction of 15 kinds of 13C marks.
Table 2: quality control standard substance (EDF-5184) analysis result (unit: ng/kg)
(2) actual sample.
Choose six soils and sediments samples that may affect by same pollution source, be numbered S1-S6, S1, S2, S3 are pedotheque, and S4, S5, S6 are sediment sample.Adopt this experimental technique, determine 17 kinds of PCDD/Fs of S1-S6.The recovery of precision and the agent of the recovery (OPR) each compound isotopic dilution in each compound recovery of 43 ~ 100%, 12C-PCDD/Fs at 90-140%.It is 49-106% that the isotope of 15 kinds of PCDD/Fs of S1-S6 sample extracts the interior mark recovery.Specifically as shown in Table 3.
The analysis result of table 3 S1-S6 soils and sediments sample
(3) the 15 dioxin international comparison activities
Participate in the 15 dioxin international comparison activity (" the 15th round of the 2010international laboratory comparison of dioxin "), comprise four sediment sample (sediment A, sediment B, sediment C, sediment D).
What this was participated in presides over " taking turns the comparison of dioxin International Laboratory in 2010 the 15 " activity by Orebro university of Sweden, " International Laboratory comparison work group " chairman Albertvan professor Bavel, and the laboratory effectively participated in has 64.According to the statistical method of international comparison in the past, deviation is greater than 2 times of standard deviations (SD), i.e. Z=(x-X)/SD, | the data that Z| is greater than 2 are considered to exceptional value, and exceptional value is not used in assembly average.The relative standard deviation of single measurement data is defined as R=(x-X) * 100/X, can think the degree of closeness of single measurement data and mean value.
Table 4 the 15 sediment of international comparison and the measurement result of standard solution
Continuous upper table
Participate in the ensemble average analysis level in all laboratories analyzed from statistics (table 4), carry out judgment experiment ability from the compare of analysis result in this laboratory report value and other laboratories.Can judge from result, the Z value of each sample is basic in [-2,2], and the measurement result in this laboratory is for satisfied.That is, the PCDD/Fs in this lab analysis sediment and similar matrix thereof reaches or approaches advanced international standards.
Above-mentioned embodiment is only the preferred embodiment of the present invention, can not limit protection scope of the present invention with this, and the change of any unsubstantiality that those skilled in the art does on the basis of invention and replacement all belong to the present invention's scope required for protection.
Claims (2)
1. a method for purifying dioxin-like chemicals in environmental matrix extraction liquid, is characterized in that comprising following purifying step:
1) filler pre-treatment:
Neutral silica gel: be placed in exsiccator with muffle furnace 550 DEG C activation more than 12h and save backup;
Alkali alumina: activate 8 hours with 500 DEG C of muffle furnaces, be placed in exsiccator and be down to room temperature, sealing is preserved, and uses in 72 hours;
Fu Luoli magnesium silicate: 140 DEG C of activation more than 24h, taking-up is placed in exsiccator and is down to room temperature interior use half an hour;
Anhydrous sodium sulfate: 450 DEG C of more than roasting 4h, are cooled to room temperature, is contained in be placed in exsiccator in port grinding bottle and saves backup;
Cotton and the silica sand of silanized glass: 450 DEG C of roastings more than 4 hours are for subsequent use;
Cotton and filter paper: with after methylene chloride ultrasonic half an hour three times, after vacuum drains solvent, be placed in exsiccator and save backup;
2) compound adhesive column purification: the filler in described compound adhesive post by lower and on be followed successively by glass wool, silica sand, neutral silica gel, alkaline silica gel, neutral silica gel, acidic silica gel, anhydrous sodium sulfate, first infiltrate by normal hexane pre-flush, then after environmental matrices extract being transferred to this compound adhesive post, with hexane; Described compound adhesive post selection blade diameter length ratio is the normal pressure glass chromatography column of 1:5 ~ 10, lower bands tetrafluoro section door; Wherein, glass wool filler height 1cm, quartz sand filler height 1cm, neutral silica gel 3g, alkaline silica gel 4g, neutral silica gel 3g, acidic silica gel 40g, anhydrous sodium sulfate height 1cm;
3) Fu Luoli magnesium silicate-alkali alumina combined column purification: the filler in described Fu Luoli magnesium silicate-alkali alumina combined column by lower and on be followed successively by silanized glass cotton, silica sand, Fu Luoli magnesium silicate, alkali alumina, anhydrous sodium sulfate, then infiltrate by normal hexane pre-flush; Wherein silanized glass cotton packing height 1cm, quartz sand filler height 1cm, Fu Luoli magnesium silicate 1g, alkali alumina 1g, anhydrous sodium sulfate height 1cm; By step 2) after environmental matrices extract after purification is transferred to this Fu Luoli magnesium silicate-alkali alumina combined column, be first the normal hexane/methylene chloride mixed liquor wash-out of 95:5 with volume ratio, then obtain with dichloromethane eluent and contain the sample solution of PCDD/Fs.
2. the method for purifying dioxin-like chemicals in environmental matrix extraction liquid as claimed in claim 1, is characterized in that: the blade diameter length ratio of Fu Luoli magnesium silicate-alkali alumina combined column is 1:5 ~ 10.
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| CN103645086B (en) * | 2013-12-30 | 2015-11-18 | 宁波市环境监测中心 | The pre-treating method of multiclass persistence organic pollutant in environment purification medium while of a kind of |
| CN104258596A (en) * | 2014-09-25 | 2015-01-07 | 上海市农业科学院 | Solid-phase extraction column for enriching and purifying deoxidized nivalenol |
| CN105259013A (en) * | 2015-10-26 | 2016-01-20 | 哈尔滨工业大学 | Method for purifying bisphenol compound in surface water sample extraction liquid |
| CN105974001A (en) * | 2016-04-21 | 2016-09-28 | 广州普诺环境检测技术服务有限公司 | Method for pretreating soil or sediment sample and method for determining dioxin |
| CN107064382B (en) * | 2017-03-15 | 2019-11-05 | 广州普诺环境检测技术服务有限公司 | A kind of preprocess method of plant leaf blade and the measuring method of dioxin |
| CN112666295A (en) * | 2020-12-30 | 2021-04-16 | 生态环境部华南环境科学研究所 | Method for extracting, cooperatively separating and detecting polychlorinated biphenyl and dioxin in soil |
| CN115963213A (en) * | 2023-02-08 | 2023-04-14 | 生态环境部华南环境科学研究所(生态环境部生态环境应急研究所) | Method for purifying and separating dioxin, polychlorinated biphenyl and polybrominated diphenyl ether in environmental medium |
| CN116908356A (en) * | 2023-07-19 | 2023-10-20 | 生态环境部华南环境科学研究所(生态环境部生态环境应急研究所) | Purifying device and method for brominated dioxin compounds in environmental sample |
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| CN102235949B (en) * | 2010-04-30 | 2013-01-30 | 中国科学院大连化学物理研究所 | Gas phase-liquid phase on-line combined dioxin sample purification device |
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