CN104655473A - Method for detecting trace mercury in water - Google Patents
Method for detecting trace mercury in water Download PDFInfo
- Publication number
- CN104655473A CN104655473A CN201510088571.XA CN201510088571A CN104655473A CN 104655473 A CN104655473 A CN 104655473A CN 201510088571 A CN201510088571 A CN 201510088571A CN 104655473 A CN104655473 A CN 104655473A
- Authority
- CN
- China
- Prior art keywords
- mercury
- water
- ionic liquid
- mercury ion
- enrichment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a method for enriching and detecting trace mercury in water. The method comprises the following steps: extracting mercury in water samples by utilizing an N-octyl pyridine ionic liquid, forming an emulsion in water by introducing perchlorate to the ionic liquid solution, and thus quickly extracting the mercury in water, and realizing the enriching of the trace mercury in water; enabling an extraction phase to be dissolved in a moderate amount of acetonitrile solution, releasing the mercury in the extraction phase, and performing electrochemical detection by using acetonitrile as a solvent. The method provided by the invention is used for improving the sensitivity and selectivity of the existing electrochemical mercury measurement method, and can be applied to the field/laboratory detection of the trace mercury in the water.
Description
Technical field
The present invention relates to trace element and detect analysis technical field, relate more specifically to a kind of method detecting Determination of Trace Mercury In Water.
Background technology
Mercury is a kind of heavy metal element having harm, due to its biological accumulation, even if content is very micro-in water environment, still can cause murder by poisoning to the ecosystem.In CNS GB3838-2002 (" GB3838-2002 water environment quality standard "), require that in I, II class water quality, mercury content is less than 0.00005 milligrams per liter, namely 0.05 microgram often rises.Multiple conventional detection method, such as ultraviolet-visible pectrophotometer method, flame atomic absorption method etc., be all not enough to the mercury identifying low content like this.
Electrochemical Stripping voltammetry is a kind of detection method measuring heavy metal ion in solution, is characterized in that instrument is simple, highly sensitive, is thus suitable for Site Detection or on-line monitoring.The method detects lead, cadmium, copper, zinc plasma in water, and detection limit can be low to moderate microgram and often rise, and has had commercialization instrument available, but the method still cannot meet the detection limit of mercury at present.On the other hand, there is contents of many kinds of heavy metal ion in actual water sample to be detected, their content is likely significantly higher than the content of mercury simultaneously.When implementing the deposition step of stripping voltammetry, excessive copper easily and mercury formation alloy, causes the stripping overlap of peaks of copper and mercury, cannot Measurement accuracy mercury content.Thus urgently find and a kind of improve stripping voltammetry sensitivity and optionally method.
In analytical chemistry field, extraction is a kind of method of effective raising testing concentration.Such as often utilize chelate extraction method to extract in analytical chemistry and enriched in metals ion, but the selection specificity of chelate to mercury and copper conventional is at present not high, metallic ion and chelate are combined closely, and lose reactivity, cause it cannot be compatible with stripping voltammetry.In addition, traditional extracting process needs organic solvent, the contaminated environment and organic reagent easily volatilizees; Extraction process needs, with special container, water and organic solvent convection current are mixed the long period, is thus difficult to implement at the scene.
Thus, in prior art field, there is no a kind of scheme and can solve the portable test problems of high-sensitivity measurement and scene simultaneously.
Summary of the invention
In view of this, fundamental purpose of the present invention is the method providing Trace Hg in a kind of measure water, thus it is easy to realize checkout equipment, can avoid effective effect of the element disturbance testing results such as copper.
To achieve these goals, as one aspect of the present invention, the invention provides the method for mercury ion in a kind of enrichment water, comprise the following steps:
The ionic liquid as extraction agent is added in pending water sample;
The reagent that described extraction phase can be made to become microlayer model is added in described pending water sample;
Be separated described microlayer model, obtain the mercury ion of enrichment.
Wherein, the kation of described ionic liquid is N-octylpyridinium, 2-methyl-N-octyl pyridine, 3-methyl-N-octyl pyridine or 4-methyl-N-octyl pyridine.
Wherein, the negative ion of described ionic liquid is tetrafluoroborate [BF
4]
-, two trifluoromethanesulfonamide [Tf
2n]
-, trifluoromethayl sulfonic acid root [TfO]
-or perfluorobutane sulfonate [NfO]
-.
Wherein, described ionic liquid is [OPy]
+[BF
4]
-, [OPy]
+[Tf
2n]
-, [OPy]
+[TfO]
-, [OPy]
+[NfO]
-or [4MOPy]
+[BF
4]
-.
Wherein, the concentration of the ionic liquid added in described pending water sample is saturation concentration or close to saturation concentration.
Wherein, the described reagent that extraction phase can be made to become microlayer model is the reagent containing perchlorate anion.
Wherein, the described reagent containing perchlorate anion is perchloric acid or lithium perchlorate.
As another aspect of the present invention, the invention provides a kind of method detecting Determination of Trace Mercury In Water, comprise the following steps:
The ionic liquid as extraction agent is added in pending water sample;
Be separated the described extraction phase containing ionic liquid, be dissolved in appropriate acetonitrile to discharge the mercury ion wherein extracted;
Employing Electrochemical Stripping voltammetry detects the trace amount mercury ion in above-mentioned acetonitrile solution.
Described method also comprises: before being dissolved in acetonitrile by described extraction phase, adopts the method for mercury ion in the enrichment water as above described in any one to be enriched in microlayer model by mercury ion, and described microlayer model is dissolved in the step in described acetonitrile.
Wherein, described Electrochemical Stripping voltammetry adopts gold electrode as working electrode.
Known based on technique scheme, the amount of reagent that method of the present invention consumes is little, processing ease, speed is fast, and necessary instrument equipment is comparatively simple, is easy to carry about with one, because of but a kind of quick, portable and high-sensitive mercury detection scheme, be specially adapted to the Site Detection of mercury pollution in water environment.Enrichment of the present invention and detection method all can be implemented at the scene, thus significantly improve the ageing of mercury pollution monitoring; And when it can be used as test in laboratory method, relatively existing method also possesses the simple and lower-cost advantage of supports conditions.
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of the method for enrichment trace mercury ion in water of the present invention.
Embodiment
For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in further detail.
Ionic liquid (Ionic Liquids) is the ionic compound for liquid under a large class normal temperature, non-volatile, easily reclaims.Ionic liquid is generally made up of anions and canons, and its cationic is generally the positively charged compound such as imidazoles, pyridine substituent, and negative ion can be the multiple acid ions such as tetrafluoro boric acid, acetic acid, Loprazolam.By changing the composition of anions and canons, the multifrequency nature such as the fusing point of adjustable ionic liquid, density, water-soluble, viscosity, dissolving power.
The present invention by using ionic liquid as extractant, and implements anodic stripping voltammetry and successfully solves the not high and problem be easily disturbed of Electrochemical Stripping voltammetry sensitivity in acetonitrile, is particularly suitable for Site Detection and on-line monitoring.
As preferably, the kation of ionic liquid of the present invention can be N-octylpyridinium (N-octylpyridinium, [OPy]
+), 2-methyl-N-octyl pyridine (2-methyl-N-octylpyridinium, [2MOPy]
+), 3-methyl-N-octyl pyridine (3-methyl-N-octylpyridinium, [3MOPy]
+) or 4-methyl-N-octyl pyridine (4-methyl-N-octylpyridinium, [4MOPy]
+), its molecular formula is as follows:
Negative ion is such as tetrafluoroborate ([BF
4]
-), two trifluoromethanesulfonamide ([Tf
2n]
-), trifluoromethayl sulfonic acid root ([TfO]
-), perfluorobutane sulfonate ([NfO]
-).
Embodiment
In a preferred embodiment, the present invention tests 5 kinds of ionic liquids, and its kation is respectively N-octylpyridinium ([OPy]
+) and 4-methyl-N-octyl pyridine ([4MOPy]
+), negative ion is respectively tetrafluoroborate ([BF
4]
-), two trifluoromethanesulfonamide ([Tf
2n]
-), trifluoromethayl sulfonic acid root ([TfO]
-), perfluorobutane sulfonate ([NfO]
-).Can find that the partition factor of each ionic liquid to each heavy metal ion is as shown in table 1 from test result.
Partition factor is under equilibrium state, and something ratio of concentration in concentration and aqueous phase in extraction phase, has reacted the extracting power size of extractant to something.Further experiment shows, the kation of ionic liquid is N-octylpyridinium, and during the methyl substitute of N-octylpyridinium, all has certain specificity extracting power to mercury.Negative ion is then relevant to solubleness in maximum enrichment times and water etc.
Table 1 five kinds of ionic liquids extract the partition factor of various heavy metal ion from water
Traditional liquid-liquid extraction method needs to shake the long period by after extractant and water mixing, for making extract in two alternate abundant exchanges and reaching balance, generally needs dozens of minutes to a few hours.In order to adapt to the needs of Site Detection, the present invention proposes one liquid-phase micro extraction technique fast.Be characterized in allowing extraction phase in water, form a large amount of superfine little microlayer model, the contact surface area of extraction phase and aqueous phase significantly increases.Extract can pass through two-phase interface rapidly, rate of extraction is significantly improved, is as short as in several minutes and completes.Its principle first makes extraction phase be dissolved completely in water, and close to saturation solubility, then add a kind of electrolyte of special selection, this electrolyte can reduce the solubleness of extraction phase in water, makes solution supersaturation, and namely extraction phase is separated out and formed aforesaid microlayer model.
Below with N-octylpyridinium tetrafluoro boric acid ([OPy]
+[BF
4]
-) ionic liquid is the preferred embodiment that example elaborates the method for measurement Determination of Trace Mercury In Water of the present invention.
First N-octylpyridinium tetrafluoro boric acid ([OPy] is adopted
+[BF
4]
-) ionic liquid is as extractant.The saturation solubility of N-octylpyridinium tetrafluoro boric acid in water is 2.6%.
In tip centrifuge tube, add the water sample to be measured after clearing up, then add the N-octylpyridinium tetrafluoro boric acid of mass ratio 2.4%, fully concussion makes it dissolve completely.
Then the lithium perchlorate aqueous solution taking a morsel dense, pouring into fast in above-mentioned solution and to shake for several times, solution presents muddiness at once.
Above-mentioned emulsion centrifuge 20 minutes, can obtain a small amount of ion liquid abstraction phase bottom centrifuge tube.Through inductivity coupled plasma mass spectrometry test, in ion liquid abstraction original solution about 90% mercury ion, and other metallic ions of < 1%.Carefully the water on upper strata is removed, then add be equivalent to original solution volume 1/10th acetonitrile buffer with dissolved ions liquid.Comprise perchloric acid that 40 mMs often rise and the lithium chloride that 0.6 mM often rises in acetonitrile buffer as supporting electrolyte, wherein perchloric acid also can substitute with the lithium perchlorate of equivalent volumetric molar concentration, and lithium chloride also can substitute with the hydrochloric acid of equivalent volumetric molar concentration.
Through said process, mercury ion, by ion liquid abstraction, enters acetonitrile solution, and ultimate density improves 10 times.And other metallic ions are not extracted, do not enter in final solution, thus method significantly improves selectivity and the sensitivity of mercury measurement.
The equipment that above-mentioned employing electrochemical process measures mercury content can adopt commercially available electrochemical workstation (Gamry Reference 600), working electrode is the golden disk electrode of finished product, adopt platinum to electrode, contrast electrode adopts the silver/silver chloride electrode of finished product.Concrete testing process can use anodic stripping voltammetry program, and sedimentation time is chosen according to measurement range.The concentration measured is lower, chooses sedimentation time longer.Coordinate magnetic agitation to improve rate of sedimentation during deposition.
Differential pulse voltammetry scanning sequence is adopted during stripping step.Through experimental verification, under one group of experiment condition optimized, be that 0-5 microgram often rises to the measure linear scope of mercury, detection limit 0.05 microgram often rises, and meets GB I, II class surface water testing requirement.
Try out through actual detection, large relative to the scheme pervasive device build of high-sensitivity measurement in prior art, energy consumption is high, special gas is needed to work, thus can only run in the lab, the ageing poor present situation of result, when method of the present invention carries out environmental monitoring, have employed can the electrochemical analyser of miniaturization, and strengthen its sensitivity by enriching step, enriching step adopts the microlayer model extraction of ionic liquid, thus speed is fast, step is simple, consume little, do not need mixing and lessivation for a long time, do not need temperature-pressure, the problem that in classic method, organic reagent volatilization is polluted is not had yet, thus outstanding advantages is possessed.
Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. the method for mercury ion in enrichment water, comprises the following steps:
The ionic liquid as extraction agent is added in pending water sample;
The reagent that described extraction phase can be made to become microlayer model is added in described pending water sample;
Be separated described microlayer model, obtain the mercury ion of enrichment.
2. the method for mercury ion in enrichment water according to claim 1, the kation of wherein said ionic liquid is N-octylpyridinium, 2-methyl-N-octyl pyridine, 3-methyl-N-octyl pyridine or 4-methyl-N-octyl pyridine.
3. the method for mercury ion in enrichment water according to claim 1, the negative ion of wherein said ionic liquid is tetrafluoroborate [BF
4]
-, two trifluoromethanesulfonamide [Tf
2n]
-, trifluoromethayl sulfonic acid root [TfO]
-or perfluorobutane sulfonate [NfO]
-.
4. the method for mercury ion in enrichment water according to claim 1, wherein said ionic liquid is [OPy]
+[BF
4]
-, [OPy]
+[Tf
2n]
-, [OPy]
+[TfO]
-, [OPy]
+[NfO]
-or [4MOPy]
+[BF
4]
-.
5. the method for mercury ion in enrichment water according to claim 1, the concentration wherein adding the ionic liquid in described pending water sample is saturation concentration or close to saturation concentration.
6. the method for mercury ion in enrichment water according to claim 1, the wherein said reagent that extraction phase can be made to become microlayer model is the reagent containing perchlorate anion.
7. the method for mercury ion in enrichment water according to claim 6, the wherein said reagent containing perchlorate anion is perchloric acid or lithium perchlorate.
8. detect a method for Determination of Trace Mercury In Water, comprise the following steps:
The ionic liquid as extraction agent is added in pending water sample;
Be separated the described extraction phase containing ionic liquid, be dissolved in appropriate acetonitrile to discharge the mercury ion wherein extracted;
Employing Electrochemical Stripping voltammetry detects the trace amount mercury ion in above-mentioned acetonitrile solution.
9. the method for detection Determination of Trace Mercury In Water according to claim 8, also be included in before described extraction phase is dissolved in acetonitrile, adopt the method for mercury ion in the enrichment water as described in claim 1 to 7 any one to be enriched in microlayer model by mercury ion, and described microlayer model is dissolved in the step in described acetonitrile.
10. the method for detection Determination of Trace Mercury In Water according to claim 9, wherein said Electrochemical Stripping voltammetry adopts gold electrode as working electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510088571.XA CN104655473B (en) | 2015-02-26 | 2015-02-26 | Enrichment and the method for detection Determination of Trace Mercury In Water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510088571.XA CN104655473B (en) | 2015-02-26 | 2015-02-26 | Enrichment and the method for detection Determination of Trace Mercury In Water |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104655473A true CN104655473A (en) | 2015-05-27 |
| CN104655473B CN104655473B (en) | 2017-08-11 |
Family
ID=53246861
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510088571.XA Active CN104655473B (en) | 2015-02-26 | 2015-02-26 | Enrichment and the method for detection Determination of Trace Mercury In Water |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104655473B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105866213A (en) * | 2016-06-21 | 2016-08-17 | 河南理工大学 | Mercury ion selective electrode based on sulfydryl functionalized ionic liquid-carboxylated multi-walled carbon nanotube and preparation method and application thereof |
| CN110308189A (en) * | 2019-06-28 | 2019-10-08 | 湖北科技学院 | A kind of Screen-printed electrochemical biosensor and its application for mercury ion detecting |
| CN111389049A (en) * | 2020-03-31 | 2020-07-10 | 浙江大学 | Liquid-liquid micro-extraction method for ultra-micro sample |
| CN113788788A (en) * | 2021-07-23 | 2021-12-14 | 浙江工业大学 | Fluorescent ionic liquid and synthesis method and application thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102798657A (en) * | 2012-09-04 | 2012-11-28 | 中国水产科学研究院黄海水产研究所 | Site fast detection method for copper, zinc, lead and cadmium as heavy metals in seawater |
-
2015
- 2015-02-26 CN CN201510088571.XA patent/CN104655473B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102798657A (en) * | 2012-09-04 | 2012-11-28 | 中国水产科学研究院黄海水产研究所 | Site fast detection method for copper, zinc, lead and cadmium as heavy metals in seawater |
Non-Patent Citations (4)
| Title |
|---|
| DANIEL MARTÍN-YERGA等: "Electrochemical determination of mercury: A review", 《TALANTA》 * |
| H.M. AL-SAIDI等: "The recent developments in dispersive liquid–liquid microextraction for preconcentration and determination of inorganic analytes", 《JOURNAL OF SAUDI CHEMICAL SOCIETY》 * |
| KERSTIN LEOPOLD等: "Preconcentration techniques for the determination of mercury species in natural waters", 《TRENDS IN ANALYTICAL CHEMISTRY》 * |
| 孙浩等: "离子液体萃取水中汞离子的研究", 《第六届全国环境化学大会》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105866213A (en) * | 2016-06-21 | 2016-08-17 | 河南理工大学 | Mercury ion selective electrode based on sulfydryl functionalized ionic liquid-carboxylated multi-walled carbon nanotube and preparation method and application thereof |
| CN110308189A (en) * | 2019-06-28 | 2019-10-08 | 湖北科技学院 | A kind of Screen-printed electrochemical biosensor and its application for mercury ion detecting |
| CN110308189B (en) * | 2019-06-28 | 2024-04-16 | 湖北科技学院 | Silk-screen printing electrochemical sensor for mercury ion detection and application thereof |
| CN111389049A (en) * | 2020-03-31 | 2020-07-10 | 浙江大学 | Liquid-liquid micro-extraction method for ultra-micro sample |
| CN113788788A (en) * | 2021-07-23 | 2021-12-14 | 浙江工业大学 | Fluorescent ionic liquid and synthesis method and application thereof |
| CN113788788B (en) * | 2021-07-23 | 2023-12-05 | 浙江工业大学 | Fluorescent ionic liquid and synthesis method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104655473B (en) | 2017-08-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ganjali et al. | Sm3+ potentiometric membrane sensor as a probe for determination of some pharmaceutics | |
| Davarani et al. | A selective electromembrane extraction of uranium (VI) prior to its fluorometric determination in water | |
| CN103926300A (en) | Improved method for determining free chlorine ions in cement paste or mortar | |
| CN104655473A (en) | Method for detecting trace mercury in water | |
| Cheraghi et al. | Voltammetric sensing of thallium at a carbon paste electrode modified with a crown ether | |
| CN107727791A (en) | The determination method of chlorion in a kind of quartz sand | |
| Zamani et al. | Gadolinium (III) Ion‐Selective Electrode Based on 3‐Methyl‐1H‐1, 2, 4‐triazole‐5‐thiol | |
| CN102539362B (en) | Ultraviolet quantitative determination method for concentration of electrolyte of positive electrode of vanadium battery and application thereof | |
| CN102879452A (en) | Method for determining content of micro chlorine ions in surface treatment solution | |
| CN104569127A (en) | Method for determining content of trace rear earth inclusion in steel | |
| Lo et al. | Dithiocarbamate extraction and Au (III) back extraction for determination of mercury in water and biological samples by anodic stripping voltammetry | |
| CN103776823A (en) | Heavy-metal detection method, as well as test paper and preparation method thereof | |
| CN104569104A (en) | Tin (II) ion-selective electrode and preparation method thereof and method for measuring tin (II) ion concentration | |
| FUJINAGA et al. | Use of a Ternary Mixture as a Solvent in Polarographic Analysis | |
| CN103018398B (en) | Quantitative detection method for corrosive sulphur in insulating oil | |
| CN102901765B (en) | Potentiometric titration method for measuring content of Hg<2+> in solution | |
| CN110220856A (en) | The method that Flow Injection Analysis detects chloride ion content in the electrodeposit liquid of electrolytic copper foil | |
| Okugaki et al. | Development of high performance electrochemical solvent extraction method | |
| CN104569105A (en) | Copper ion-selective electrode and method for measuring copper ion concentration by using copper ion-selective electrode | |
| TWI447386B (en) | Chloride ion-selective electrode | |
| Zutshi | Introduction to polarography and allied techniques | |
| CN104655762B (en) | Method for determining content of anions in cleaning fluid of nuclear pump | |
| CN103822855B (en) | The method measuring metal extraction agent optimum extraction condition | |
| CN103675074A (en) | Method for continuously determining content of zinc and cadmium in zinc sulfate procedure | |
| CN101614716B (en) | Methods for indirectly determining sulfur content of oil field waste water and analyzing valence of sulfur |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |