WO2009064044A1 - On-line analysis system for heavy metal using an electrochemical analysis method - Google Patents

On-line analysis system for heavy metal using an electrochemical analysis method Download PDF

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Publication number
WO2009064044A1
WO2009064044A1 PCT/KR2008/001965 KR2008001965W WO2009064044A1 WO 2009064044 A1 WO2009064044 A1 WO 2009064044A1 KR 2008001965 W KR2008001965 W KR 2008001965W WO 2009064044 A1 WO2009064044 A1 WO 2009064044A1
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WO
WIPO (PCT)
Prior art keywords
electrode
heavy metal
solution
enriched
analysis system
Prior art date
Application number
PCT/KR2008/001965
Other languages
French (fr)
Inventor
Hee Jin Yang
Min Jin Ha
Hyung Soo Park
Sun Il Yang
Moon Sik Hyun
Hong Suk Kim
Byung Sun Park
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Korea Biosystems Corp.
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Publication date
Application filed by Korea Biosystems Corp. filed Critical Korea Biosystems Corp.
Priority to CN2008801246459A priority Critical patent/CN101910831A/en
Publication of WO2009064044A1 publication Critical patent/WO2009064044A1/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/28—Electrolytic cell components
    • G01N27/30—Electrodes, e.g. test electrodes; Half-cells
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/28—Electrolytic cell components
    • G01N27/30—Electrodes, e.g. test electrodes; Half-cells
    • G01N27/38—Cleaning of electrodes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/416—Systems
    • G01N27/42—Measuring deposition or liberation of materials from an electrolyte; Coulometry, i.e. measuring coulomb-equivalent of material in an electrolyte
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/416—Systems
    • G01N27/48—Systems using polarography, i.e. measuring changes in current under a slowly-varying voltage

Definitions

  • the present invention relates to an on-line analysis system for heavy metal using an electrochemical analysis method, and more particularly, to an on-line analysis system for heavy metal using an electrochemical analysis method capable of reducing generation of environmental oontamination materials and improving surface stability and reproducibility.
  • GC gas chromatography
  • ICP inductively coupled plasma
  • AS atomic absorption spectroscopy
  • AES atomic emission spectroscopy
  • measurement devices in which spectroscopy is used including major components such as a light source, are very expensive, and exchange and A/S of the components require additional maintenance and management cost.
  • a dropping mercury electrode method may cause breakage of a mercury electrode when a conductive medium of undiluted mercury solution is used, making it difficult to obtain stable and continuous measurement.
  • the present invention is directed to an on-line analysis system for heavy metal using an electrochemical analysis method capable of reducing generation of environmental contamination materials and improving surface stability and reproducibility.
  • One aspect of the present invention provides an on-line analysis system for heavy metal using an electrochemical analysis method including a working electrode for measuring the type and concentration of heavy metal by applying a voltage for a certain time to enrich heavy metal ions existing in a sample solution, and gradually applying an opposite voltage to strip an enriched material to thereby measure a current, characterized in that the working electrode is formed of an enriched metal electrode in which a metal solution is adsorbed onto a bottom electrode to form an electrode film.
  • the enriched metal electrode may be formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and simultaneously enriching heavy metal ions existing in the sample solution.
  • the enriched metal electrode may be formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and then enriching heavy metal ions existing in the sample solution.
  • the metal solution may be formed of any one of a bismuth solution and a gold solution
  • the enriched metal electrode may be formed of any one of an enriched bismuth electrode and an enriched gold electrode.
  • the enriched bismuth electrode may be formed by selectively adsorbing the bismuth solution onto any one of a glassy carbon electrode and a bismuth rod electrode as a conductive medium that constitutes the bottom electrode.
  • the enriched gold electrode may be formed by selectively adsorbing the gold solution onto any one of a glassy carbon electrode and a gold rod electrode as a conductive medium that constitutes the bottom electrode.
  • the enriched metal electrode may be formed by selectively adsorbing a solution having good reaction with respect to heavy metal ions to be measured, selected from the bismuth solution and the gold solution, onto the bottom electrode.
  • the bottom electrode may be formed of any one of conductive media such as a glassy carbon electrode, a bismuth rod electrode, and a gold rod electrode.
  • the working electrode may be provided over an electrochemical cell, into which a sample solution dissociated into heavy metal ions by at least one of hydrochloric acid and nitric acid in a pre-processing device is introduced.
  • a reference electrode and a counter electrode may be further provided over the electrochemical cell.
  • a constant voltage unit to which the working electrode, the reference electrode, and the counter electrode are connected, may be controlled by a processing unit which applies a potential to the respective electrodes and detects a response signal corresponding thereto.
  • the processing unit may analyze the response signal and display the analyzed response signal through a display unit.
  • the metal ions adsorbed onto the surface of the bottom electrode and the heavy metal ions remaining on the electrochemical cell may be cleaned by at least one of an ultrasonic vibrator and distilled water.
  • a stirrer may be further installed under the electrochemical cell to stir the sample solution.
  • a conductive medium of the working electrode is formed of a metal solution which is not mercury and is harmless to a human body, generation of contamination materials can be suppressed to perform environmentfriendly and stable measurement.
  • FIG. 1 is a schematic front view of an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention
  • FIG. 2 is a block diagram of the on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention
  • FIG. 3 shows graphs in which lead is measured in various electrolytes using
  • FIG. 4 shows graphs of current versus bismuth concentration and deposition time in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a third exemplary embodiment of the present invention
  • FIG. 5 shows graphs in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fourth exemplary embodiment of the present invention
  • FIG. 6 shows graphs of correlation coefficients between CDncentrations of heavy metals and current values of FIG. 5;
  • FIG. 7 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a glassy carbon electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fifth exemplary embodiment of the present invention
  • FIG. 8 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a bismuth rod electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fifth exemplary embodiment of the present invention
  • FIG. 9 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIGS. 7 and 8;
  • FIG. 10 shows graphs representing concentration variations of copper under the oondition of different concentrations of lead, cadmium, and zinc in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a sixth exemplary embodiment of the present invention
  • FIG. 11 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 10;
  • FIG. 12 shows graphs in which arsenic is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a seventh exemplary embodiment of the present invention
  • FIG. 13 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 12;
  • FIG. 14 shows graphs in which antimony is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with an eighth exemplary embodiment of the present invention.
  • FIG. 15 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 14.
  • FIG. 1 is a schematic front view of an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention
  • FIG. 2 is a block diagram of the on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention.
  • the on-line analysis system for heavy metal using an electrochemical analysis method may include an analysis unit 10, a reagent storage unit 60, and a controller 7Q
  • the reagent storage unit 60 stores a reagent such as an electrolyte and a standard solution required for analysis.
  • An electrochemical cell 43 may be provided in the analysis unit 10 to measure heavy metal ions contained in a supplied sample solution.
  • a working electrode 42 provided in the analysis unit 10 and in which heavy metal ions contained in the sample solution are enriched and stripped, may be formed of an enriched metal electrode, in which a metal ion other than mercury is adsorbed to form an electrode film.
  • the analysis unit 10 may include a pre-processing device 20, a thermostat 30, the electrochemical cell 43, and a constant voltage unit 5Q
  • the pre-processing device 20 may include a heater 22 and a stirrer 24.
  • the heater 22 may heat a sample solution to a temperature of 120 to 150 C.
  • the stirrer 24 may supply nitric acid or hydrochloric acid into the sample solution to remove organic materials, thereby preventing existence of various types of compounds in the sample solution.
  • the pre-processing device 20 can dissociate the heavy metals contained in the sample solution into ions to more smoothly perform electrochemical reaction.
  • the sample solution pre-processed in the pre-processing device 20 is supplied into the electrochemical cell 40 provided inside the thermostat 30 via a sample supply unit 52.
  • Movement of the sample solution may be controlled by a multi-channel valve 54 for selectively closing and opening a fluid pipe through which the sample solution flows.
  • the electrochemical cell 43 may be formed of a synthetic resin material such as plastic.
  • the sample solution moved through the sample supply unit 52 is contained in the electrochemical cell 43.
  • a working electrode 42, a reference electrode 44, and a counter electrode 46 may be provided over the electrochemical cell 43 to measure voltage and current.
  • the reference electrode 44 is formed of an Ag/ AgCl electrode to control a potential of the working electrode 42 and measure the potential.
  • the counter electrode 46 may be formed of a platinum (Pt) wire and may have a large area to perform smooth flow of current.
  • the working electrode 42 may be formed of an enriched metal electrode, in which a potential is applied to the bottom electrode to adsorb a metal solution onto the surface of the bottom electrode to thereby form an electrode film.
  • the metal solution may be formed of a bismuth solution or a gold solution, not being limited thereto, various metal solutions may be used.
  • the working electrode 42 is fabricated by adsorbing a metal solution formed of bismuth or gold which is less harmful than mercury, thereby reducing generation of contamination.
  • a precursor of the metal solution can be used by appropriately diluting metal ions dissociated in acid using a solution such as a metal standard solution.
  • the bottom electrode constituting the enriched metal electrode may be formed of any one of a glassy carbon electrode, a bismuth rod electrode, and a gold rod electrode.
  • the glassy carbon electrode has a good electrode surface, a potential can be applied for a certain time to adsorb the metal solution, thereby readily forming a metal electrode.
  • the bismuth rod electrode and the gold rod electrode are the same as the precursor for enriching a metal, the bismuth rod electrode has advantages of good resolution in analyzing heavy metal ions due to good adsorption and high conductivity between the rod surface and the solution.
  • a bismuth solution and a gold solution may be selectively adsorbed onto the glassy carbon electrode.
  • the bismuth solution may be adsorbed onto the bismuth rod electrode, and the gold solution may be adsorbed onto the gold rod electrode.
  • the bismuth solution may be adsorbed onto the surface of the glassy carbon electrode or the bismuth rod electrode to form an enriched bismuth electrode.
  • the gold solution may be adsorbed onto the surface of the glassy carbon electrode or the gold rod electrode to form an enriched gold electrode.
  • a solution having good reaction with respect to a heavy metal ion to be measured, selected from the bismuth solution and the gold solution, may be adsorbed.
  • an enriched bismuth electrode or an enriched gold electrode may be formed.
  • the concentration and amount of the metal solution adsorbed onto the bottom electrode can be adjusted, it is possible to appropriately adjust the thickness of an electrode film adsorbed onto and formed on the bottom electrode.
  • the enriched metal electrode is obtained by applying a potential to the bottom electrode to adsorb the metal solution onto the bottom electrode and form an electrode film. Then, although not limited hereto, a voltage-current value may be measured by enriching heavy metal ions existing in the sample solution and dissociating the heavy metal ions.
  • the enriched metal electrode may be formed in a manner that, when a potential is applied to the bottom electrode to adsorb the metal solution onto the bottom electrode, a voltage is also applied to the sample solution such that a desired amount of heavy metal ions are simultaneously enriched onto the bottom electrode in the sample solution. Then, the enriched metal electrode may be reduced to dissociate the metal solution and the heavy metal ions, thereby measuring a voltage-current value.
  • the working electrode 42, the reference electrode 44, and the counter electrode 46 may be connected to the constant voltage unit 5Q
  • the constant voltage unit 50 may apply a potential or voltage to the respective electrodes 42, 44 and 46, and detect a response corresponding thereto.
  • the constant voltage unit 50 may be connected to a processing unit 72 provided in the controller 7Q
  • the processing unit 72 may be a personal computer (PC), and may analyze a signal detected by the constant voltage unit 50, input measurement parameters, and control various devices provided in the analysis unit 10 through software.
  • PC personal computer
  • the processing unit 72 may be connected to a display unit 74, and the display unit 74 may display measurement values and instrument states in real time.
  • controller 70 may further include various power supplies for supplying power to drive various pumps, valves, sensors, and so on, provided in the analysis unit IQ
  • controller 70 may further include a control device (not shown), a universal serial bus (USB) port (not shown) for sending measurement values, and so on.
  • control device not shown
  • USB universal serial bus
  • the processing unit 72 controls the pump, the stirrer 24, the multi-channel valve 54, and so on, through digital output, and the resultant analysis data can be oommunicated with the exterior through analog output.
  • Unmanned automation may be performed through hardware/software provided to the pre-processing device 20, the electrochemical cell 40, the pump, the multi-channel valve 54, the constant voltage unit 50, and so on.
  • an ultrasonic vibrator 34 may be provided under or beside the electrochemical cell 40 to readily clean the electrochemical cell 4Q
  • a stirrer 32 may be provided under or beside the electrochemical cell 40 to evenly mix a sample and a buffer solution in the electrochemical cell 40 upon measurement of heavy metal. As a result, it is possible to more evenly enrich heavy metal ions onto the working electrode 42.
  • the enriched metal electrode may be cleaned by distilled water as well as the ultrasonic vibrator 34.
  • the metal ions adsorbed onto the enriched metal electrode may be cleaned by the above cleaning step.
  • the heavy metal ions enriched onto the enriched metal electrode may also be cleaned therewith.
  • the metal solution such as a bismuth solution or a gold solution may be selectively and rapidly adsorbed onto the cleaned bottom electrode, various types of enriched metal electrodes can be readily produced.
  • the pre-processing device 20, the electrochemical cell 40, and a fluid pipe, and so on may be cleaned by a detergent solution fabricated by appropriately diluting acid, and a waste solution generated through the cleaning may be stored in a waste solution storage tank 80
  • the reagent storage unit 60 may include an electrolyte storage unit 62 for storing an electrolyte supplied into the electrochemical cell 40, and a standard solution storage unit 64 for storing a standard solution containing various predetermined amounts of heavy metals.
  • a separate storage unit may be further provided.
  • the electrolyte, the standard solution, and the sample solution can be quantitatively supplied by a pump (not shown) connected to the analysis unit IQ
  • the sample solution pre-processed in the pre-processing device 20 is supplied into the electrochemical cell 40 to be stirred.
  • a voltage is applied to the bottom electrode to enrich heavy metal ions contained in the sample solution, thereby forming the enriched metal electrode.
  • the sample contains bismuth and gold of 100 to 500 ⁇ g/L concentration
  • the buffer solution uses a chloroacetate buffer.
  • a predetermined amount of heavy metal standard solution may be injected into the sample with reference to a baseline, in which a sample having no heavy metal is measured, to uniformly increase the concentration of the heavy metal in the sample.
  • the sample solution supplied into the electrochemical cell 40 is exposed to a frequency of 30 to 60Hz for 60 to 240 seconds to perform a deposition step of depositing the heavy metal ions onto the enriched metal electrode.
  • the enriched metal electrode is reduced to dissociate the enriched heavy metal ions and measure a voltage-current value (a stripping step), thereby analyang the type and concentration of the heavy metals.
  • FIG. 3 shows graphs in which lead is measured in various electrolytes using Difference Pulse Stripping Voltammetry (DPSV) and Square Wave Stripping Voltammetry (SWSV) in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a second exemplary embodiment of the present invention.
  • DPSV Difference Pulse Stripping Voltammetry
  • SWSV Square Wave Stripping Voltammetry
  • an electrolyte was formed of chloroacetate, acetate, phosphate, and HCl+ KNO 3 buffer by adjusting their composition to an appropriate pH.
  • a scanning method used Difference Pulse Stripping Voltammetry (DPSV) and Square Wave Stripping Voltammetry (SWSV).
  • the DPSV represented the highest value of 2.533/zA in an acetate buffer electrolyte of Q06mol/L
  • the SWSV represented the highest value of 1Q16Q ⁇ A in a chloroacetate buffer electrolyte of Qlmol/L.
  • FIG. 4 shows graphs of current versus bismuth concentration and deposition time in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a third exemplary embodiment of the present invention.
  • FIG. 5 shows graphs in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a fourth exemplary embodiment of the present invention
  • FIG. 6 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 5.
  • the working electrode 42 was used as the enriched bismuth electrode to perform quantitative analysis of heavy metal ions of lead (Pb), cadmium (Cd), anc (Zn), and copper (Cu).
  • the heavy metals were increased to lOO ⁇ g/L, 200/zg/L, 300,ug/L, ⁇ O ⁇ g/L and 500//g/L, respectively, to be injected.
  • FIG. 7 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a glassy carbon electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in ac- oordance with a fifth exemplary embodiment of the present invention
  • FIG. 8 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a bismuth rod electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a fifth exemplary embodiment of the present invention
  • FIG. 9 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIGS. 7 and 8.
  • the heavy metals were increased to 100 ⁇ g/L, 200/zg/L, 300 ⁇ /g/L, ⁇ O ⁇ gfL and 500/zg/L, respectively, to be injected.
  • FIG. 10 shows graphs representing concentration variations of copper under the condition of different concentrations of lead, cadmium, and zinc in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a sixth exemplary embodiment of the present invention
  • FIG. 11 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. IQ
  • FIG. 12 shows graphs in which arsenic is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a seventh exemplary embodiment of the present invention
  • FIG. 13 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 12.
  • the arsenic was increased to lOO ⁇ g/L, 200/ ⁇ g/L, 300,ug/L, 4)0 ⁇ g/L and 500/ ⁇ g/L, respectively, to be injected.
  • FIG. 14 shows graphs in which antimony is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with an eighth exemplary embodiment of the present invention
  • FIG. 15 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 14.
  • the antimony was increased to 100/zg/L, 200 ⁇ g/L, 300#g/L, 400/ ⁇ g/L and 500//g/L, respectively, to be injected.

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Abstract

Provided is an on-line analysis system for heavy metal using an electrochemical analysis method capable of reducing generation of environmental contamination materials and improving surface stability and reproducibility. The on-line analysis system includes a working electrode for measuring the type and concentration of heavy metal by applying a voltage for a certain time to enrich heavy metal ions existing in a sample solution, and gradually applying an opposite voltage to strip an enriched material to thereby measure current, characterized in that the working electrode is formed of an enriched metal electrode in which a metal solution is adsorbed onto a bottom electrode to form an electrode film.

Description

Description
ON-LINE ANALYSIS SYSTEM FOR HEAVY METAL USING AN ELECTROCHEMICAL ANALYSIS METHOD
Technical Field
[1] The present invention relates to an on-line analysis system for heavy metal using an electrochemical analysis method, and more particularly, to an on-line analysis system for heavy metal using an electrochemical analysis method capable of reducing generation of environmental oontamination materials and improving surface stability and reproducibility. Background Art
[2] Generally used quantitative methods of a very small amount of heavy metal may be classified into equipment-using methods such as gas chromatography (GC), inductively coupled plasma (ICP) spectroscopy, atomic absorption spectroscopy (AAS), and atomic emission spectroscopy (AES), and electrochemical methods.
[3] However, not only does the AAS consume much time in measurement, measurement devices thereof are also very expensive, and thus, its maintenance cost is also very high, thereby complicating adjustment of equipment environment for measurement and increasing analysis cost.
[4] In particular, measurement devices in which spectroscopy is used, including major components such as a light source, are very expensive, and exchange and A/S of the components require additional maintenance and management cost.
[5] In addition, the devices cannot be readily applied to the field due to their structure and principles which can cause problems in reproducibility and accuracy.
[6] Meanwhile, the electrochemical measurement methods are being widely used as relatively rapid and economic analysis methods in comparison with the spectroscopy.
[7] However, among the electrochemical measurement methods, a dropping mercury electrode method may cause breakage of a mercury electrode when a conductive medium of undiluted mercury solution is used, making it difficult to obtain stable and continuous measurement.
[8] In addition, in the case of a hanging mercury drop electrode (HMDE) and a mercury thin film electrode (MTFE), an undiluted mercury solution is used as a conductive medium, which increases probability of generating secondary environmental pollution and decreases analysis reproducibility and reliability.
[9] Moreover, in the case of the mercury thin film electrode, there is an added trouble that every measurement must be performed after forming a mercury film, making it difficult to perform automation for continuous measurements. Disclosure of Invention Technical Problem
[10] The present invention is directed to an on-line analysis system for heavy metal using an electrochemical analysis method capable of reducing generation of environmental contamination materials and improving surface stability and reproducibility. Technical Solution
[11] One aspect of the present invention provides an on-line analysis system for heavy metal using an electrochemical analysis method including a working electrode for measuring the type and concentration of heavy metal by applying a voltage for a certain time to enrich heavy metal ions existing in a sample solution, and gradually applying an opposite voltage to strip an enriched material to thereby measure a current, characterized in that the working electrode is formed of an enriched metal electrode in which a metal solution is adsorbed onto a bottom electrode to form an electrode film.
[12] Here, the enriched metal electrode may be formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and simultaneously enriching heavy metal ions existing in the sample solution.
[13] In addition, the enriched metal electrode may be formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and then enriching heavy metal ions existing in the sample solution.
[14] The metal solution may be formed of any one of a bismuth solution and a gold solution, and the enriched metal electrode may be formed of any one of an enriched bismuth electrode and an enriched gold electrode.
[15] Furthermore, the enriched bismuth electrode may be formed by selectively adsorbing the bismuth solution onto any one of a glassy carbon electrode and a bismuth rod electrode as a conductive medium that constitutes the bottom electrode.
[16] In addition, the enriched gold electrode may be formed by selectively adsorbing the gold solution onto any one of a glassy carbon electrode and a gold rod electrode as a conductive medium that constitutes the bottom electrode.
[17] Further, the enriched metal electrode may be formed by selectively adsorbing a solution having good reaction with respect to heavy metal ions to be measured, selected from the bismuth solution and the gold solution, onto the bottom electrode.
[18] Furthermore, the bottom electrode may be formed of any one of conductive media such as a glassy carbon electrode, a bismuth rod electrode, and a gold rod electrode.
[19] In addition, the working electrode may be provided over an electrochemical cell, into which a sample solution dissociated into heavy metal ions by at least one of hydrochloric acid and nitric acid in a pre-processing device is introduced.
[20] Further, a reference electrode and a counter electrode may be further provided over the electrochemical cell.
[21] Furthermore, a constant voltage unit, to which the working electrode, the reference electrode, and the counter electrode are connected, may be controlled by a processing unit which applies a potential to the respective electrodes and detects a response signal corresponding thereto.
[22] In addition, the processing unit may analyze the response signal and display the analyzed response signal through a display unit.
[23] Further, the metal ions adsorbed onto the surface of the bottom electrode and the heavy metal ions remaining on the electrochemical cell may be cleaned by at least one of an ultrasonic vibrator and distilled water.
[24] Furthermore, a stirrer may be further installed under the electrochemical cell to stir the sample solution.
Advantageous Effects
[25] Effects of an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with an exemplary embodiment of the present invention are as follows:
[26] First, since a working electrode is formed of an enriched metal electrode in which a limited amount of metal solution is adsorbed onto a bottom electrode to form an electrode film, its manufacturing process is simple.
[27] Second, since a conductive medium of the working electrode is formed of a metal solution which is not mercury and is harmless to a human body, generation of contamination materials can be suppressed to perform environmentfriendly and stable measurement.
[28] Third, since a material having good reaction with respect to heavy metal to be analyzed can be selectively adsorbed onto a bottom electrode, it is possible to perform various and accurate measurement depending on the type of the heavy metal to be analyzed.
[29] Fourth, since the metal solution adsorbed onto the enriched metal electrode can be cleaned by an ultrasonic vibrator and distilled water, it is possible to keep the electrode surface clean without the trouble of periodically polishing the electrode surface. [30] Fifth, since adsorption and cleaning of the metal solution on the bottom electrode can be rapidly and readily performed, continuous measurement and analysis in real time of heavy metal ions can be performed simultaneously. Brief Description of the Drawings
[31] FIG. 1 is a schematic front view of an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention;
[32] FIG. 2 is a block diagram of the on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention;
[33] FIG. 3 shows graphs in which lead is measured in various electrolytes using
Difference Pulse Stripping Voltammetry (DPSV) and Square Wave Stripping Voltammetry (SWSV) in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a seoond exemplary embodiment of the present invention;
[34] FIG. 4 shows graphs of current versus bismuth concentration and deposition time in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a third exemplary embodiment of the present invention;
[35] FIG. 5 shows graphs in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fourth exemplary embodiment of the present invention;
[36] FIG. 6 shows graphs of correlation coefficients between CDncentrations of heavy metals and current values of FIG. 5;
[37] FIG. 7 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a glassy carbon electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fifth exemplary embodiment of the present invention;
[38] FIG. 8 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a bismuth rod electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in acoordance with a fifth exemplary embodiment of the present invention;
[39] FIG. 9 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIGS. 7 and 8;
[40] FIG. 10 shows graphs representing concentration variations of copper under the oondition of different concentrations of lead, cadmium, and zinc in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a sixth exemplary embodiment of the present invention;
[41] FIG. 11 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 10;
[42] FIG. 12 shows graphs in which arsenic is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a seventh exemplary embodiment of the present invention;
[43] FIG. 13 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 12;
[44] FIG. 14 shows graphs in which antimony is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with an eighth exemplary embodiment of the present invention; and
[45] FIG. 15 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 14.
[46] * Description of Major Reference Numerals*
[47] 10: analysis unit 20: pre-processing device
[48] 30: thermostat 32: stirrer
[Φ] 34: ultrasonic vibrator 40: electrochemical cell
[50] 42: working electrode 50: constant voltage unit
[51] 54: multi-channel valve 60: reagent storage unit
[52] 70: controller
Best Mode for Carrying Out the Invention
[53] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[54] FIG. 1 is a schematic front view of an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention, and FIG. 2 is a block diagram of the on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a first exemplary embodiment of the present invention.
[55] As shown in FIGS. 1 and 2, the on-line analysis system for heavy metal using an electrochemical analysis method may include an analysis unit 10, a reagent storage unit 60, and a controller 7Q Here, the reagent storage unit 60 stores a reagent such as an electrolyte and a standard solution required for analysis. An electrochemical cell 43 may be provided in the analysis unit 10 to measure heavy metal ions contained in a supplied sample solution. In addition, the reagent storage unit 60 and the analysis unit 10 may be controlled by the controller 7Q At this time, a working electrode 42, provided in the analysis unit 10 and in which heavy metal ions contained in the sample solution are enriched and stripped, may be formed of an enriched metal electrode, in which a metal ion other than mercury is adsorbed to form an electrode film. As a result, generation of contamination materials can be suppressed and a metal solution having good reaction with respect to heavy metal to be analyzed can be selectively adsorbed onto a bottom electrode, thereby enabling improvement in analysis reproducibility and accurate measurement.
[56] Specifically, the analysis unit 10 may include a pre-processing device 20, a thermostat 30, the electrochemical cell 43, and a constant voltage unit 5Q
[57] In addition, the pre-processing device 20 may include a heater 22 and a stirrer 24.
[58] The heater 22 may heat a sample solution to a temperature of 120 to 150 C.
[59] Further, the stirrer 24 may supply nitric acid or hydrochloric acid into the sample solution to remove organic materials, thereby preventing existence of various types of compounds in the sample solution.
[60] Therefore, the pre-processing device 20 can dissociate the heavy metals contained in the sample solution into ions to more smoothly perform electrochemical reaction.
[61] The sample solution pre-processed in the pre-processing device 20 is supplied into the electrochemical cell 40 provided inside the thermostat 30 via a sample supply unit 52.
[62] At this time, the sample solution is moved by pump power provided from a pump
(not shown). Movement of the sample solution may be controlled by a multi-channel valve 54 for selectively closing and opening a fluid pipe through which the sample solution flows.
[63] Meanwhile, the electrochemical cell 43 may be formed of a synthetic resin material such as plastic. The sample solution moved through the sample supply unit 52 is contained in the electrochemical cell 43.
[64] Here, a working electrode 42, a reference electrode 44, and a counter electrode 46 may be provided over the electrochemical cell 43 to measure voltage and current.
[65] The reference electrode 44 is formed of an Ag/ AgCl electrode to control a potential of the working electrode 42 and measure the potential. The counter electrode 46 may be formed of a platinum (Pt) wire and may have a large area to perform smooth flow of current. [66] In addition, the working electrode 42 may be formed of an enriched metal electrode, in which a potential is applied to the bottom electrode to adsorb a metal solution onto the surface of the bottom electrode to thereby form an electrode film. [67] At this time, while the metal solution may be formed of a bismuth solution or a gold solution, not being limited thereto, various metal solutions may be used. [68] As described above, the working electrode 42 is fabricated by adsorbing a metal solution formed of bismuth or gold which is less harmful than mercury, thereby reducing generation of contamination. [69] Here, a precursor of the metal solution can be used by appropriately diluting metal ions dissociated in acid using a solution such as a metal standard solution. [70] Meanwhile, the bottom electrode constituting the enriched metal electrode may be formed of any one of a glassy carbon electrode, a bismuth rod electrode, and a gold rod electrode. [71] Here, since the glassy carbon electrode has a good electrode surface, a potential can be applied for a certain time to adsorb the metal solution, thereby readily forming a metal electrode. [72] In addition, since the bismuth rod electrode and the gold rod electrode are the same as the precursor for enriching a metal, the bismuth rod electrode has advantages of good resolution in analyzing heavy metal ions due to good adsorption and high conductivity between the rod surface and the solution. [73] A bismuth solution and a gold solution may be selectively adsorbed onto the glassy carbon electrode. [74] In addition, the bismuth solution may be adsorbed onto the bismuth rod electrode, and the gold solution may be adsorbed onto the gold rod electrode. [75] As described above, the bismuth solution may be adsorbed onto the surface of the glassy carbon electrode or the bismuth rod electrode to form an enriched bismuth electrode. [76] Further, the gold solution may be adsorbed onto the surface of the glassy carbon electrode or the gold rod electrode to form an enriched gold electrode. [77] Here, a solution, having good reaction with respect to a heavy metal ion to be measured, selected from the bismuth solution and the gold solution, may be adsorbed. [78] As a result, an enriched bismuth electrode or an enriched gold electrode may be formed. [79] At this time, since the concentration and amount of the metal solution adsorbed onto the bottom electrode can be adjusted, it is possible to appropriately adjust the thickness of an electrode film adsorbed onto and formed on the bottom electrode.
[80] As a result, it is possible to adjust sensitivity of the enriched metal electrode, adjust concentration of the enriched heavy metal and analyze the <x>ncentration.
[81] Therefore, since the heavy metal ions enriched for a short time can be stripped through electrolysis, it is possible to rapidly obtain measurement values.
[82] In addition, when a high-speed scanning voltammetry is applied during a stripping process, it is possible to obtain a peak-shaped analysis signal capable of readily performing data analysis.
[83] The enriched metal electrode is obtained by applying a potential to the bottom electrode to adsorb the metal solution onto the bottom electrode and form an electrode film. Then, although not limited hereto, a voltage-current value may be measured by enriching heavy metal ions existing in the sample solution and dissociating the heavy metal ions.
[84] That is, the enriched metal electrode may be formed in a manner that, when a potential is applied to the bottom electrode to adsorb the metal solution onto the bottom electrode, a voltage is also applied to the sample solution such that a desired amount of heavy metal ions are simultaneously enriched onto the bottom electrode in the sample solution. Then, the enriched metal electrode may be reduced to dissociate the metal solution and the heavy metal ions, thereby measuring a voltage-current value.
[85] Meanwhile, the working electrode 42, the reference electrode 44, and the counter electrode 46 may be connected to the constant voltage unit 5Q
[86] In addition, preferably, the constant voltage unit 50 may apply a potential or voltage to the respective electrodes 42, 44 and 46, and detect a response corresponding thereto.
[87] The constant voltage unit 50 may be connected to a processing unit 72 provided in the controller 7Q
[88] Here, the processing unit 72 may be a personal computer (PC), and may analyze a signal detected by the constant voltage unit 50, input measurement parameters, and control various devices provided in the analysis unit 10 through software.
[89] The processing unit 72 may be connected to a display unit 74, and the display unit 74 may display measurement values and instrument states in real time.
[90] In addition, the controller 70 may further include various power supplies for supplying power to drive various pumps, valves, sensors, and so on, provided in the analysis unit IQ
[91] Further, the controller 70 may further include a control device (not shown), a universal serial bus (USB) port (not shown) for sending measurement values, and so on.
[92] Furthermore, preferably, the processing unit 72 controls the pump, the stirrer 24, the multi-channel valve 54, and so on, through digital output, and the resultant analysis data can be oommunicated with the exterior through analog output.
[93] Unmanned automation may be performed through hardware/software provided to the pre-processing device 20, the electrochemical cell 40, the pump, the multi-channel valve 54, the constant voltage unit 50, and so on.
[94] Meanwhile, an ultrasonic vibrator 34 may be provided under or beside the electrochemical cell 40 to readily clean the electrochemical cell 4Q
[95] In addition, a stirrer 32 may be provided under or beside the electrochemical cell 40 to evenly mix a sample and a buffer solution in the electrochemical cell 40 upon measurement of heavy metal. As a result, it is possible to more evenly enrich heavy metal ions onto the working electrode 42.
[96] Meanwhile, the enriched metal electrode may be cleaned by distilled water as well as the ultrasonic vibrator 34.
[97] Therefore, the metal ions adsorbed onto the enriched metal electrode may be cleaned by the above cleaning step. Of course, at this time, the heavy metal ions enriched onto the enriched metal electrode may also be cleaned therewith.
[98] As described above, since the metal solution such as a bismuth solution or a gold solution may be selectively and rapidly adsorbed onto the cleaned bottom electrode, various types of enriched metal electrodes can be readily produced.
[99] Moreover, since a material, having good reaction with respect to heavy metal to be analyzed, can be selectively adsorbed onto the bottom electrode, it is possible to improve analysis reproduction and perform more accurate measurement.
[100] In addition, the pre-processing device 20, the electrochemical cell 40, and a fluid pipe, and so on, may be cleaned by a detergent solution fabricated by appropriately diluting acid, and a waste solution generated through the cleaning may be stored in a waste solution storage tank 80
[101] Meanwhile, the reagent storage unit 60 may include an electrolyte storage unit 62 for storing an electrolyte supplied into the electrochemical cell 40, and a standard solution storage unit 64 for storing a standard solution containing various predetermined amounts of heavy metals. In addition, if necessary, a separate storage unit may be further provided.
[102] The electrolyte, the standard solution, and the sample solution can be quantitatively supplied by a pump (not shown) connected to the analysis unit IQ
[103] An analysis process of heavy metal ions using the enriched metal electrode will be described below.
[104] First, a voltage is applied to the bottom electrode to adsorb the metal solution onto the surface of the bottom electrode.
[105] Then, the sample solution pre-processed in the pre-processing device 20 is supplied into the electrochemical cell 40 to be stirred.
[106] In addition, a voltage is applied to the bottom electrode to enrich heavy metal ions contained in the sample solution, thereby forming the enriched metal electrode.
[107] When a voltage is applied to the bottom electrode to adsorb the metal solution onto the surface of the bottom electrode, heavy metal ions contained in the sample solution can be simultaneously adsorbed to form the enriched metal electrode.
[108] Here, the sample contains bismuth and gold of 100 to 500μg/L concentration, and the buffer solution uses a chloroacetate buffer.
[109] In addition, a predetermined amount of heavy metal standard solution may be injected into the sample with reference to a baseline, in which a sample having no heavy metal is measured, to uniformly increase the concentration of the heavy metal in the sample.
[110] At this time, the sample solution supplied into the electrochemical cell 40 is exposed to a frequency of 30 to 60Hz for 60 to 240 seconds to perform a deposition step of depositing the heavy metal ions onto the enriched metal electrode.
[I l l] Then, a quiet step is maintained.
[112] Next, the enriched metal electrode is reduced to dissociate the enriched heavy metal ions and measure a voltage-current value (a stripping step), thereby analyang the type and concentration of the heavy metals. Mode for the Invention
[113] FIG. 3 shows graphs in which lead is measured in various electrolytes using Difference Pulse Stripping Voltammetry (DPSV) and Square Wave Stripping Voltammetry (SWSV) in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a second exemplary embodiment of the present invention.
[114] As shown in FIG. 3, an electrolyte was formed of chloroacetate, acetate, phosphate, and HCl+ KNO3 buffer by adjusting their composition to an appropriate pH. [115] In addition, a scanning method used Difference Pulse Stripping Voltammetry (DPSV) and Square Wave Stripping Voltammetry (SWSV).
[116] As a result of measuring lead of 100μg/L in various electrolytes, the DPSV represented the highest value of 2.533/zA in an acetate buffer electrolyte of Q06mol/L, and the SWSV represented the highest value of 1Q16Q^A in a chloroacetate buffer electrolyte of Qlmol/L.
[117] FIG. 4 shows graphs of current versus bismuth concentration and deposition time in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a third exemplary embodiment of the present invention.
[118] As shown in FIG. 4, when a heavy metal ion is measured using the enriched bismuth electrode, in order to check a current value depending on bismuth concentration, the test was performed by varying the bismuth concentration from 100^g/L to 500,ug/L.
[119] Eventually, it was shown that the higher the bismuth concentration, the lower the current value.
[120] As a result, it can be anticipated that adsorption of the other metals except the bismuth is prohibited, as the bismuth concentration is increased. Therefore, it will be appreciated that an appropriate amount of the bismuth is 100 to 200^g/L.
[121] FIG. 5 shows graphs in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a fourth exemplary embodiment of the present invention, and FIG. 6 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 5.
[122] As shown in FIG. 5, the working electrode 42 was used as the enriched bismuth electrode to perform quantitative analysis of heavy metal ions of lead (Pb), cadmium (Cd), anc (Zn), and copper (Cu).
[123] The heavy metals were increased to lOOμg/L, 200/zg/L, 300,ug/L, ΦOμg/L and 500//g/L, respectively, to be injected.
[124] As a result, as the concentrations of the heavy metals were increased, the current values were also increased so that the respective correlation coefficients R 2 exhibited a straightness of 0.9 or more as shown in FIG. 6.
[125] Therefore, it will be appreciated that quantitative analysis of the respective heavy metal ions can be performed at the enriched bismuth electrode.
[126] FIG. 7 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a glassy carbon electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in ac- oordance with a fifth exemplary embodiment of the present invention, FIG. 8 shows a graph in which various heavy metals are quantitatively analyzed using an enriched bismuth electrode formed of a bismuth rod electrode in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a fifth exemplary embodiment of the present invention, and FIG. 9 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIGS. 7 and 8.
[127] As shown in FIGS. 7 and 8, quantitative analysis of heavy metal ions of lead (Pb), cadmium (Cd), and zinc (Zn) was performed using the enriched bismuth electrode formed by adsorbing the bismuth solution onto the glassy carbon electrode, and the enriched bismuth electrode formed by adsorbing the bismuth solution onto the bismuth rod electrode.
[128] The heavy metals were increased to 100μg/L, 200/zg/L, 300^/g/L, ΦOμgfL and 500/zg/L, respectively, to be injected.
[129] As a result, as the concentrations of the heavy metals were increased, the current values were also increased so that the respective correlation coefficients R 2 exhibited a straightness of Q9 or more as shown in FIG. 9.
[130] Therefore, it will be appreciated that quantitative analysis can be performed with respect to the respective heavy metal ions, even though the enriched bismuth electrode is formed using the bottom electrode as the glassy carbon electrode or the bismuth rod electrode.
[131] FIG. 10 shows graphs representing concentration variations of copper under the condition of different concentrations of lead, cadmium, and zinc in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a sixth exemplary embodiment of the present invention, and FIG. 11 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. IQ
[132] As shown in FIG. 10, in a state that Pb/Cd/Zn is maintained at concentrations of lOμg/L and lOOμg/L, copper was increased to 50^g/L, lOOμg/L, 150^g/L, 200/^g/L, 250/^g/L and 300^g/L and in-situ injected thereinto.
[133] As a result, when the copper was added into lead, cadmium and zinc, a current value increased proportionally regardless of concentrations of the lead, cadmium and the zinc, and the correlation coefficients R 2 exhibited a straightness of Q9 or more as shown in FIG. 11.
[134] Therefore, it will be appreciated that quantitative analysis of copper can be performed regardless of concentrations of lead, cadmium, and zinc.
[135] FIG. 12 shows graphs in which arsenic is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with a seventh exemplary embodiment of the present invention, and FIG. 13 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 12.
[136] As shown in FIGS. 12 and 13, quantitative analysis of arsenic (As) was performed using the enriched gold electrode formed by adsorbing the gold solution onto the glassy carbon electrode, and the enriched gold electrode formed by adsorbing the gold solution onto the gold rod electrode.
[137] The arsenic was increased to lOOμg/L, 200/^g/L, 300,ug/L, 4)0^g/L and 500/^g/L, respectively, to be injected.
[138] As a result, as the concentrations of the arsenic were increased, the current values were also increased so that the correlation coefficients R 2 exhibited a straightness of Q9 or more as shown in FIG. 13.
[139] Therefore, it will be appreciated that quantitative analysis of arsenic can be performed, even though the enriched gold electrode is formed using the bottom electrode as the glassy carbon electrode or the gold rod electrode.
[140] FIG. 14 shows graphs in which antimony is quantitatively analyzed using enriched gold electrodes formed of a glassy carbon electrode and a gold rod electrode, respectively, in an on-line analysis system for heavy metal using an electrochemical analysis method in accordance with an eighth exemplary embodiment of the present invention, and FIG. 15 shows graphs of correlation coefficients between concentrations of heavy metals and current values of FIG. 14.
[141] As shown in FIGS. 14 and 15, quantitative analysis of antimony (Sb) was performed using the enriched gold electrode formed by adsorbing the gold solution onto the glassy carbon electrode, and the enriched gold electrode formed by adsorbing the gold solution onto the gold rod electrode.
[142] The antimony was increased to 100/zg/L, 200^g/L, 300#g/L, 400/^g/L and 500//g/L, respectively, to be injected.
[143] As a result, as the concentrations of the antimony were increased, the current values were also increased so that the correlation coefficients R 2 exhibited a straightness of Q9 or more as shown in FIG. 15.
[144] Therefore, it will be appreciated that quantitative analysis of antimony can be performed, even though the enriched gold electrode is formed using the bottom electrode as the glassy carbon electrode or the gold rod electrode. While the invention has been shown and described with reference to m certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

Claims
[1] An on-line analysis system for heavy metal using an electrochemical analysis method including a step of using a working electrode for measuring the type and concentration of heavy metal by applying a voltage for a certain time to enrich heavy metal ions existing in a sample solution, and gradually applying an opposite voltage to strip an enriched material to thereby measure a current, wherein the working electrode includes an enriched metal electrode in which a metal solution is adsorbed onto a bottom electrode to form an electrode film.
[2] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 1 , wherein the enriched metal electrode is formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and simultaneously enriching heavy metal ions existing in the sample solution.
[3] The on-line analysis system for heavy metal using an electrochemical analysis method according to claim 1 , wherein the enriched metal electrode is formed by adsorbing the metal solution onto the surface of the bottom electrode by the voltage applied to the bottom electrode, and then enriching heavy metal ions existing in the sample solution.
[4] The on-line analysis system for heavy metal using an electrochemical analysis method acαording to claim 1, wherein the metal solution includes any one of a bismuth solution and a gold solution, and the enriched metal electrode is formed of any one of an enriched bismuth electrode and an enriched gold electrode.
[5] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 4, wherein the enriched bismuth electrode is formed by selectively adsorbing the bismuth solution onto any one of a glassy carbon electrode and a bismuth rod electrode as a conductive medium that constitutes the bottom electrode.
[6] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 4, wherein the enriched gold electrode is formed by selectively adsorbing the gold solution onto any one of a glassy carbon electrode and a gold rod electrode as a oonductive medium that constitutes the bottom electrode.
[7] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 4, wherein the enriched metal electrode is formed by selectively adsorbing a solution having good reaction with respect to heavy metal ions to be measured, selected from the bismuth solution and the gold solution, onto the bottom electrode.
[8] The on-line analysis system for heavy metal using an electrochemical analysis method according to claim 7, wherein the bottom electrode is formed of any one of conductive media such as a glassy carbon electrode, a bismuth rod electrode, and a gold rod electrode.
[9] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 1 , wherein the working electrode is provided over an electrochemical cell, into which a sample solution dissociated into heavy metal ions by at least one of hydrochloric acid and nitric acid in a pre-processing device is introduced.
[10] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 9, wherein a reference electrode and a counter electrode are further provided over the electrochemical cell.
[11] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 10, wherein a constant voltage unit, to which the working electrode, the reference electrode, and the oounter electrode are connected, is controlled by a processing unit which applies a potential to the respective electrodes and detects a response signal corresponding thereto.
[12] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 11, wherein the processing unit analyzes the response signal and displays the analyzed response signal through a display unit.
[13] The on-line analysis system for heavy metal using an electrochemical analysis method acαording to claim 9, wherein the metal ions adsorbed onto the surface of the bottom electrode and the heavy metal ions remaining on the electrochemical cell are cleaned by at least one of an ultrasonic vibrator and distilled water.
[14] The on-line analysis system for heavy metal using an electrochemical analysis method acoording to claim 9, further comprising a stirrer provided under the electrochemical cell to stir the sample solution.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101907599A (en) * 2010-07-21 2010-12-08 宇星科技发展(深圳)有限公司 All-in-one heavy metal online analyzer
CN102507713A (en) * 2011-11-08 2012-06-20 中国地质调查局水文地质环境地质调查中心 Electrochemical stripping voltammetry for continuously measuring arsenic, stibonium and lead in mine groundwater
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3855099A (en) * 1971-08-02 1974-12-17 Environmental Sciences Ass Inc Electrode for anodic stripping voltammetry
US5292423A (en) * 1991-04-09 1994-03-08 New Mexico State University Technology Transfer Corp. Method and apparatus for trace metal testing
US5391270A (en) * 1993-08-11 1995-02-21 General Electric Company Detection and measurement of heavy metals
US5672257A (en) * 1993-05-28 1997-09-30 Cranfield Biotechnology Ltd. Electrochemical metal analysis
US6527930B1 (en) * 1999-07-02 2003-03-04 Trustees Of Tufts College Microfabricated array of iridium microdisks
US6682647B1 (en) * 2000-05-10 2004-01-27 New Mexico State University Technology Transfer Corporation Bismuth-based electrochemical stripping analysis

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5389215A (en) 1992-11-05 1995-02-14 Nippon Telegraph And Telephone Corporation Electrochemical detection method and apparatus therefor
US5595635A (en) 1995-09-08 1997-01-21 The United States Of America As Represented By The Secretary Of The Navy Apparatus for measuring lead content of water
KR20020036292A (en) * 2000-11-09 2002-05-16 현문식 Detection of metal ion and measuring method
CN1540333A (en) * 2003-04-22 2004-10-27 英科新创(厦门)科技有限公司 Sensng device for detecting metallic ion
US7435320B2 (en) * 2004-04-30 2008-10-14 Advanced Technology Materials, Inc. Methods and apparatuses for monitoring organic additives in electrochemical deposition solutions

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3855099A (en) * 1971-08-02 1974-12-17 Environmental Sciences Ass Inc Electrode for anodic stripping voltammetry
US5292423A (en) * 1991-04-09 1994-03-08 New Mexico State University Technology Transfer Corp. Method and apparatus for trace metal testing
US5672257A (en) * 1993-05-28 1997-09-30 Cranfield Biotechnology Ltd. Electrochemical metal analysis
US5391270A (en) * 1993-08-11 1995-02-21 General Electric Company Detection and measurement of heavy metals
US6527930B1 (en) * 1999-07-02 2003-03-04 Trustees Of Tufts College Microfabricated array of iridium microdisks
US6682647B1 (en) * 2000-05-10 2004-01-27 New Mexico State University Technology Transfer Corporation Bismuth-based electrochemical stripping analysis

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101907599A (en) * 2010-07-21 2010-12-08 宇星科技发展(深圳)有限公司 All-in-one heavy metal online analyzer
CN102507713A (en) * 2011-11-08 2012-06-20 中国地质调查局水文地质环境地质调查中心 Electrochemical stripping voltammetry for continuously measuring arsenic, stibonium and lead in mine groundwater
CN113092564A (en) * 2019-12-23 2021-07-09 上海雄图生物科技有限公司 Method for rapidly detecting heavy metals in water
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