WO2012107081A1 - A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution - Google Patents

A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution Download PDF

Info

Publication number
WO2012107081A1
WO2012107081A1 PCT/EP2011/051822 EP2011051822W WO2012107081A1 WO 2012107081 A1 WO2012107081 A1 WO 2012107081A1 EP 2011051822 W EP2011051822 W EP 2011051822W WO 2012107081 A1 WO2012107081 A1 WO 2012107081A1
Authority
WO
WIPO (PCT)
Prior art keywords
carbonaceous material
electrode
graphite rod
aqueous solution
organic contaminants
Prior art date
Application number
PCT/EP2011/051822
Other languages
French (fr)
Inventor
Rudolf Gensler
XinHao Zhu
Original Assignee
Siemens Aktiengesellschaft
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Priority to PCT/EP2011/051822 priority Critical patent/WO2012107081A1/en
Publication of WO2012107081A1 publication Critical patent/WO2012107081A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F1/46114—Electrodes in particulate form or with conductive and/or non conductive particles between them
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
    • C02F1/4672—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electrooxydation
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
    • C25B11/042—Electrodes formed of a single material
    • C25B11/043—Carbon, e.g. diamond or graphene
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F2001/46133—Electrodes characterised by the material
    • C02F2001/46138—Electrodes comprising a substrate and a coating
    • C02F2001/46142—Catalytic coating
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F2001/46152—Electrodes characterised by the shape or form
    • C02F2001/46157—Perforated or foraminous electrodes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F2001/46152—Electrodes characterised by the shape or form
    • C02F2001/46157—Perforated or foraminous electrodes
    • C02F2001/46161—Porous electrodes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/02—Specific form of oxidant
    • C02F2305/023—Reactive oxygen species, singlet oxygen, OH radical

Definitions

  • the invention relates to a system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution.
  • Advanced electrochemical oxidation system is used for the degradation of organic contaminants in aqueous solution by generating hydroxyl radicals ( ⁇ ) on a surface of an
  • the electrode by applying suitable voltages.
  • the system uses oxidation capabilities of the hydroxyl radicals generated to degrade organic contaminants in aqueous solution.
  • the amount of hydroxyl radicals generated on the electrode surfaces depends not only on the voltages applied (generally, higher voltage corresponds to larger amount of hydroxyl radicals) but most important on the materials and configurations of the electrodes .
  • the material investigated includes metal oxides (e.g. RuOx, ZrOx, T1O 2 , Pb0 2 , etc.), platinum (Pt) , graphite and boron- doped diamond (BOD), etc. These materials were investigated for oxidation over potential efficiency; so that the
  • electrical conductivity of the electrode should be good .
  • the hydroxyl radicals can only be generated on the surface of the electrodes, in order to let the hydroxyl radicals react with the organic contaminants, the organic contaminants should diffuse onto the surfaces of the electrodes from the aqueous solution, or the hydroxyl radicals diffuse into the aqueous solution to oxidize the organic contaminants. The latter case is not favored since the life time of the
  • hydroxyl radicals is very short.
  • the hydroxyl radicals may recombine or react with water molecules easily in the aqueous solution to lose their oxidation ability. Therefore, an electrode which can concentrate contaminant from the aqueous solution onto the electrode surface efficiently is mostly desired.
  • the electrode should have good electrical conductivity, high oxygen over potential and ability to concentrate the organic contaminants on the surface of the electrode.
  • the object of the invention is to disclose a system and electrodes being used for the said system for advanced electrochemical oxidation to efficiently degrade organic contaminants in an aqueous solution.
  • the idea of the invention is to provide an electrode and a system using said electrode including an electrical coupling between a graphite rod and a carbonaceous material to provide electrical conduction between the graphite rod and the carbonaceous material for regulating electric current flow through the carbonaceous material and an aqueous solution containing contaminants electrochemically coupled to the electrode which can generate hydroxyl radicals for degrading the contaminants concentrated on the electrode surface.
  • the carbonaceous material comprises at least one of granular activated carbon and activated carbon felt. Such carbonaceous materials have high affinity to organic contaminants and large surface area for concentrating more contaminants at a surface of the
  • the graphite rod is
  • the physical contact between a surface of the graphite rod and the carbonaceous material is extended up to an entire length of the graphite rod or mesh cage, which strengthens the electrical conduction to control the electric current between the graphite of and the carbonaceous material.
  • the electrode includes a mesh cage for enclosing the carbonaceous material, wherein the mesh cage includes an opening to allow the graphite rod into the mesh cage for providing the physical coupling between the graphite rod and the carbonaceous material.
  • the mesh cage provides for structuring the electrode into a shape by encapsulating the carbonaceous material and the graphite rod together.
  • the carbonaceous material is doped with at least one of platinum, boron-doped diamond or a metal oxide. This enhances to improve oxidation over- potential and electrical conductivity of the electrode.
  • the aqueous solution is aqueous solution
  • the electrode is having at least one of plane, ring or cylinder geometry. Such geometries increase surface area of the electrode to provide efficient degradation of the contaminants using hydroxyl radicals .
  • the system includes a container comprising an inlet for allowing the aqueous solution to enter into the container and an outlet for allowing the aqueous solution to exit after degradation of the organic contaminants, wherein the electrode is arranged in the container in such a way that the aqueous solution is electrochemically coupled to the electrode for degradation of the organic contaminants after entering into the container via the inlet and exits out of the container via the outlet. This provides for continuous degradation of the contaminants in the aqueous solution.
  • FIG 1 illustrates a schematic diagram of a system for
  • FIG 2A illustrates a front-end view of an electrode having a graphite rod electrically coupled to carbonaceous material
  • FIG 2B shows top view of the electrode having the graphite rod electrically coupled to the carbonaceous material.
  • FIG 3A illustrates a front-end view of an electrode having a physical contact between a graphite rod and carbonaceous material up to a length of the rod.
  • FIG 3B shows top view of the electrode having a physical contact between the graphite rod and the carbonaceous
  • FIG 4 shows a graphical representation of electrical current flowing through carbonaceous material against the electrical potential applied to different electrodes.
  • FIG 1, FIG 2A, FIG 2B, FIG 3A, FIG 3B and FIG 4 will be used to explain aspects of embodiments illustrated by figures.
  • a system 1 being used for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution 2 includes an electrode 3 having a graphite rod 4 and electrically conductive carbonaceous material 5, coupled together to generate hydroxyl radicals at a surface 6 of the carbonaceous material 5 to degrade the contaminants present in an aqueous solution
  • the electrode 3 has the graphite rod 4 coupled to the
  • rate of generation of the hydroxyl ion is such that the hydroxyl radicals should not flow inside the aqueous solution, rather as soon as the hydroxyl radicals are
  • a mesh cage 9 is provided having an opening 10 to allow the graphite rod 4 to flexibly move inside the cage to provide a physical contact 7 between the graphite rod 4 and the carbonaceous material 5.
  • the graphite rod 4 can move inside the cage according to the physical contact 7 required between the carbonaceous material 5 and the graphite rod 4.
  • a small part of the graphite rod 4 is moved inside to provide the physical contact 7 between the graphite rod 4 and the
  • the graphite rod 4 can also move inside up to an entire length 8 of the graphite rod 4 or the mesh cage 9 to provide a larger physical contact 7 between the carbonaceous material 5 and the graphite rod 4 to
  • the mesh cage 9 has a porous structure to allow a physical interaction between the aqueous solution and the carbonaceous material 5.
  • the geometry of the mesh cage 9 can be changed according to the requirement of the geometry of the electrode 3. For large surface area of the electrode 3, plane, ring or cylinder based geometries are preferred. So, according to the preference for the geometry of the electrode 3, the geometry of the mesh cage 9 is also changed to include a planar, or a circular or a cylindrical geometry.
  • the mesh cage 9 has a size which is enough to retain the carbonaceous material 5 but to allow transportation of organic contaminants from aqueous solution 4 to the
  • the electrode 3 can include granular activated carbon, or activated carbon felt, or combination thereof as the carbonaceous material 5.
  • mesh cage 9 is not used since the activated carbon felt 5 is having a solid geometry and is wrapped easily onto the graphite rod directly.
  • the system 1 includes a container 12 having an inlet 13 for allowing the aqueous solution 2 to enter into the container 12 and an outlet 14 for allowing the aqueous solution 2 to exit after degradation of the organic contaminants.
  • the electrode 3 is arranged in the container 12 in such a way that the aqueous solution 2 is in direct contact to the electrode 3 for degradation of the organic contaminants after entering into the container 12 via the inlet 13 and exit out of the container 12 via the outlet 14.
  • the electrode 3 is placed in center of the container 12 and used as an anode.
  • a cylindrical cathode e.g. a stainless steel ring
  • the inner surface of the container 12 can be used directly as a cathode. Gap between the anode and cathode should be kept as small as possible to generate high current and also large amount of hydroxyl radicals. Small gap can also maximize contact between aqueous solution and the anode.
  • the aqueous solution includes an aqueous phase 11 of the aqueous solution such that the aqueous phase 11 is controlled to avoid physical interaction between the aqueous solution 2 and the graphite rod 4 for increasing surface area of the carbonaceous materials available to the contaminants for concentration and hence increases efficiency and rate of degradation of the contaminants.
  • the carbonaceous material 5 can be doped with platinum, boron-doped diamond or a metal oxide (e.g. RuO x , Ti0 2 , ) , or a combination thereof.
  • a metal oxide e.g. RuO x , Ti0 2 , ) , or a combination thereof.
  • Electrodes 3 with high oxygen over-potential help in generating hydroxyl radicals to oxidize contaminants. Furthermore, the doped carbonaceous material 5 forms localized electrical field among different particles of the carbonaceous material 5, which also promotes the generation of free radicals.
  • FIG 2A front-end view of an electrode 3 is illustrated and in FIG 2B, a top view of the electrode 3 is shown.
  • the electrode 3 is having a graphite rod 4 in physical contact 7 with a part of the carbonaceous material 5 inside a mesh cage 9, wherein the mesh cage 9 is having an opening 10 for allowing the graphite rod 4 to move inside the cage to be in contact with the part of the carbonaceous material 5.
  • the electrode 3 with such an arrangement can be used for degrading contaminants present in the aqueous solution by maintaining an aqueous phase 11 of the graphite rod 4 below a level of graphite rod 4 to avoid physical interaction between the graphite rod 4 and the aqueous solution, when the electrode 3 is placed inside a container 12 having aqueous solution.
  • FIG 3A front-end view of an electrode 3 is illustrated and in FIG 3B, a top view of the electrode 3 is shown.
  • the electrode 3 is having a graphite rod 4 in physical contact 7 with a part of the carbonaceous material 5 inside a mesh cage 9 over an entire length 8 of the mesh cage 9, wherein the mesh cage 9 is having an opening 10 for allowing the graphite rod 4 to move inside the cage to be in contact with the part of the
  • FIG 4 shows a graph mapping the electrical current flowing through the carbonaceous material 5 on y axis in mili-amperes (mA) against the electrical potential applied to the
  • Line A denotes to the graph plotting for the electrode 3 of FIG 2A and FIG 2B
  • Line B denoted the graph plotting for the electrode 3 of FIG 3A and 3B.
  • the Line A shows that current flowing through the carbonaceous material 5 of electrode 3 of FIG 2A and 2B is more in respect to the electrode 3 of FIG 3A and 3B
  • Line B denotes that the electrical current flow through the carbonaceous material 5 of electrode 3 of FIG 3A and 3B is better controlled in respect to the electrode 3 of FIG 2A and FIG 2B.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Water Supply & Treatment (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)

Abstract

A system (1) for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution (2) including an electrode (3) comprising a graphite rod (4) and a carbonaceous material (5) to electrically couple the graphite rod (4) to the carbonaceous material (5) for regulating electric current flow through the carbonaceous material (5), and an aqueous solution (2) comprising the organic contaminants, the aqueous solution (2) is electrochemically coupled to the electrode (3) which can generate the hydroxyl radicals at the surface (6) of the carbonaceous material (5) and concentrate the organic contaminants onto the surface (6) of the carbonaceous material (5), so that the hydroxyl radicals degrade the organic contaminants.

Description

Description
A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic
contaminants in an aqueous solution
The invention relates to a system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution.
Advanced electrochemical oxidation system is used for the degradation of organic contaminants in aqueous solution by generating hydroxyl radicals (ΌΗ) on a surface of an
electrode by applying suitable voltages. The system uses oxidation capabilities of the hydroxyl radicals generated to degrade organic contaminants in aqueous solution. The amount of hydroxyl radicals generated on the electrode surfaces depends not only on the voltages applied (generally, higher voltage corresponds to larger amount of hydroxyl radicals) but most important on the materials and configurations of the electrodes .
The material investigated includes metal oxides (e.g. RuOx, ZrOx, T1O2, Pb02, etc.), platinum (Pt) , graphite and boron- doped diamond (BOD), etc. These materials were investigated for oxidation over potential efficiency; so that the
electrode with higher oxidation over potential is able generate more hydroxyl radicals at the surface of the
electrode .
To generate hydroxyl radicals at the surface of the
electrode, electrical conductivity of the electrode should be good . As the hydroxyl radicals can only be generated on the surface of the electrodes, in order to let the hydroxyl radicals react with the organic contaminants, the organic contaminants should diffuse onto the surfaces of the electrodes from the aqueous solution, or the hydroxyl radicals diffuse into the aqueous solution to oxidize the organic contaminants. The latter case is not favored since the life time of the
hydroxyl radicals is very short. The hydroxyl radicals may recombine or react with water molecules easily in the aqueous solution to lose their oxidation ability. Therefore, an electrode which can concentrate contaminant from the aqueous solution onto the electrode surface efficiently is mostly desired. In summary, for making the system efficient for degradation of contaminants, the electrode should have good electrical conductivity, high oxygen over potential and ability to concentrate the organic contaminants on the surface of the electrode. The object of the invention is to disclose a system and electrodes being used for the said system for advanced electrochemical oxidation to efficiently degrade organic contaminants in an aqueous solution. The idea of the invention is to provide an electrode and a system using said electrode including an electrical coupling between a graphite rod and a carbonaceous material to provide electrical conduction between the graphite rod and the carbonaceous material for regulating electric current flow through the carbonaceous material and an aqueous solution containing contaminants electrochemically coupled to the electrode which can generate hydroxyl radicals for degrading the contaminants concentrated on the electrode surface. According to one embodiment, the carbonaceous material comprises at least one of granular activated carbon and activated carbon felt. Such carbonaceous materials have high affinity to organic contaminants and large surface area for concentrating more contaminants at a surface of the
carbonaceous material.
According to another embodiment, the graphite rod is
physically coupled to the carbonaceous material so that to provide a physical contact between the graphite rod and the carbonaceous material. Such physical contact provides an easy way for providing electrical conduction between the graphite rod and the carbonaceous material.
According to yet another embodiment, the physical contact between a surface of the graphite rod and the carbonaceous material is extended up to an entire length of the graphite rod or mesh cage, which strengthens the electrical conduction to control the electric current between the graphite of and the carbonaceous material.
According to an exemplary embodiment, the electrode includes a mesh cage for enclosing the carbonaceous material, wherein the mesh cage includes an opening to allow the graphite rod into the mesh cage for providing the physical coupling between the graphite rod and the carbonaceous material. The mesh cage provides for structuring the electrode into a shape by encapsulating the carbonaceous material and the graphite rod together.
According to one embodiment, the carbonaceous material is doped with at least one of platinum, boron-doped diamond or a metal oxide. This enhances to improve oxidation over- potential and electrical conductivity of the electrode.
According to another embodiment, the aqueous solution
includes an aqueous phase such that the aqueous phase is controlled to avoid physical interaction between the aqueous solution and the graphite rod. This helps to increase surface area available to the contaminants for concentration onto the carbonaceous materials and hence increases efficiency and rate of degradation of the contaminants. According to yet another embodiment, the electrode is having at least one of plane, ring or cylinder geometry. Such geometries increase surface area of the electrode to provide efficient degradation of the contaminants using hydroxyl radicals .
According to an exemplary embodiment, the system includes a container comprising an inlet for allowing the aqueous solution to enter into the container and an outlet for allowing the aqueous solution to exit after degradation of the organic contaminants, wherein the electrode is arranged in the container in such a way that the aqueous solution is electrochemically coupled to the electrode for degradation of the organic contaminants after entering into the container via the inlet and exits out of the container via the outlet. This provides for continuous degradation of the contaminants in the aqueous solution.
FIG 1 illustrates a schematic diagram of a system for
advanced electrochemical oxidation to degrade organic
contaminants in an aqueous solution. FIG 2A illustrates a front-end view of an electrode having a graphite rod electrically coupled to carbonaceous material
FIG 2B shows top view of the electrode having the graphite rod electrically coupled to the carbonaceous material.
FIG 3A illustrates a front-end view of an electrode having a physical contact between a graphite rod and carbonaceous material up to a length of the rod. FIG 3B shows top view of the electrode having a physical contact between the graphite rod and the carbonaceous
material up to the length of the rod.
FIG 4 shows a graphical representation of electrical current flowing through carbonaceous material against the electrical potential applied to different electrodes. Various embodiments are described with reference to the drawings, wherein like reference numerals are used to refer to single elements throughout. In the following description, for purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident that such embodiments may be practiced without these specific details.
While discussing each of the figures, reference signs in FIG 1, FIG 2A, FIG 2B, FIG 3A, FIG 3B and FIG 4 will be used to explain aspects of embodiments illustrated by figures.
According to FIG 1, a system 1 being used for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution 2 includes an electrode 3 having a graphite rod 4 and electrically conductive carbonaceous material 5, coupled together to generate hydroxyl radicals at a surface 6 of the carbonaceous material 5 to degrade the contaminants present in an aqueous solution
electrochemically .
The electrode 3 has the graphite rod 4 coupled to the
carbonaceous material 5 in such a way that current flowing through the carbonaceous material 5 can be controlled. Such a control of the electric current further controls a rate of generation of hydroxyl radicals to make degradation of the contaminants in the aqueous solution efficient. Life time of the hydroxyl radicals is very short and they can easily recombine or react with water molecules to lose their
activity. So, rate of generation of the hydroxyl ion is such that the hydroxyl radicals should not flow inside the aqueous solution, rather as soon as the hydroxyl radicals are
generated onto the surface 6 of carbonaceous material 5 the hydroxyl radicals should degrade the contaminants by
oxidizing the contaminants. When the hydroxyl radicals are generated at the surface 6 of the carbonaceous material 5, at the same time the
contaminants also starts concentrating at the surface 6 of the carbonaceous material 5, so that the contaminants gets degraded at the surface 6 of the carbonaceous material 5 itself, rather than degrading inside the aqueous solution.
To combine the carbonaceous material 5 and the graphite rod 4 together, a mesh cage 9 is provided having an opening 10 to allow the graphite rod 4 to flexibly move inside the cage to provide a physical contact 7 between the graphite rod 4 and the carbonaceous material 5. With this arrangement, the graphite rod 4 can move inside the cage according to the physical contact 7 required between the carbonaceous material 5 and the graphite rod 4. In the current embodiment, a small part of the graphite rod 4 is moved inside to provide the physical contact 7 between the graphite rod 4 and the
carbonaceous material 5 for just maintaining the electrical coupling between the graphite rod 4 and the carbonaceous material 5. Alternatively, the graphite rod 4 can also move inside up to an entire length 8 of the graphite rod 4 or the mesh cage 9 to provide a larger physical contact 7 between the carbonaceous material 5 and the graphite rod 4 to
strengthen the electrical coupling for controlling current flow through the carbonaceous material 5.
The mesh cage 9 has a porous structure to allow a physical interaction between the aqueous solution and the carbonaceous material 5. The geometry of the mesh cage 9 can be changed according to the requirement of the geometry of the electrode 3. For large surface area of the electrode 3, plane, ring or cylinder based geometries are preferred. So, according to the preference for the geometry of the electrode 3, the geometry of the mesh cage 9 is also changed to include a planar, or a circular or a cylindrical geometry.
The mesh cage 9 has a size which is enough to retain the carbonaceous material 5 but to allow transportation of organic contaminants from aqueous solution 4 to the
carbonaceous materials 5.
To maintain a larger surface area of the carbonaceous material 5, the electrode 3 can include granular activated carbon, or activated carbon felt, or combination thereof as the carbonaceous material 5.
In an alternate embodiment, when activated carbon felt is used 5, mesh cage 9 is not used since the activated carbon felt 5 is having a solid geometry and is wrapped easily onto the graphite rod directly.
The system 1 includes a container 12 having an inlet 13 for allowing the aqueous solution 2 to enter into the container 12 and an outlet 14 for allowing the aqueous solution 2 to exit after degradation of the organic contaminants. The electrode 3 is arranged in the container 12 in such a way that the aqueous solution 2 is in direct contact to the electrode 3 for degradation of the organic contaminants after entering into the container 12 via the inlet 13 and exit out of the container 12 via the outlet 14.
The electrode 3 is placed in center of the container 12 and used as an anode. A cylindrical cathode (e.g. a stainless steel ring) is installed closely to an inner surface of the container 12. In an alternative embodiment, the inner surface of the container 12 can be used directly as a cathode. Gap between the anode and cathode should be kept as small as possible to generate high current and also large amount of hydroxyl radicals. Small gap can also maximize contact between aqueous solution and the anode.
The aqueous solution includes an aqueous phase 11 of the aqueous solution such that the aqueous phase 11 is controlled to avoid physical interaction between the aqueous solution 2 and the graphite rod 4 for increasing surface area of the carbonaceous materials available to the contaminants for concentration and hence increases efficiency and rate of degradation of the contaminants..
In alternate embodiment, the carbonaceous material 5 can be doped with platinum, boron-doped diamond or a metal oxide (e.g. RuOx, Ti02, ) , or a combination thereof. The
carbonaceous material 5 after doping has improved
conductivity and higher oxygen over-potential. Electrodes 3 with high oxygen over-potential help in generating hydroxyl radicals to oxidize contaminants. Furthermore, the doped carbonaceous material 5 forms localized electrical field among different particles of the carbonaceous material 5, which also promotes the generation of free radicals. In FIG 2A, front-end view of an electrode 3 is illustrated and in FIG 2B, a top view of the electrode 3 is shown.
According to FIG 2A and 2B, the electrode 3 is having a graphite rod 4 in physical contact 7 with a part of the carbonaceous material 5 inside a mesh cage 9, wherein the mesh cage 9 is having an opening 10 for allowing the graphite rod 4 to move inside the cage to be in contact with the part of the carbonaceous material 5. Such arrangement only
provides the physical contact 7 between the graphite rod 4 and the carbonaceous material 5 to maintain an electrical coupling between the graphite rod 4 and carbonaceous material 5 to control electric current flow through the carbonaceous material 5. The electrode 3 with such an arrangement can be used for degrading contaminants present in the aqueous solution by maintaining an aqueous phase 11 of the graphite rod 4 below a level of graphite rod 4 to avoid physical interaction between the graphite rod 4 and the aqueous solution, when the electrode 3 is placed inside a container 12 having aqueous solution. In FIG 3A, front-end view of an electrode 3 is illustrated and in FIG 3B, a top view of the electrode 3 is shown.
According to FIG 3A and 3B, the electrode 3 is having a graphite rod 4 in physical contact 7 with a part of the carbonaceous material 5 inside a mesh cage 9 over an entire length 8 of the mesh cage 9, wherein the mesh cage 9 is having an opening 10 for allowing the graphite rod 4 to move inside the cage to be in contact with the part of the
carbonaceous material 5. Such arrangement provides a better contact between the graphite rod 4 and carbonaceous material 5, so as to strengthen control of the current flow through the carbonaceous material 5. In this embodiment, the aqueous phase 11 of the aqueous solution while degradation of the contaminants cannot be kept lower than the graphite rod 4, as the electrochemical coupling between the carbonaceous
material 5 and the aqueous solution cannot be maintained.
FIG 4 shows a graph mapping the electrical current flowing through the carbonaceous material 5 on y axis in mili-amperes (mA) against the electrical potential applied to the
electrodes 3 on x axis in volts (V) . Line A denotes to the graph plotting for the electrode 3 of FIG 2A and FIG 2B, while Line B denoted the graph plotting for the electrode 3 of FIG 3A and 3B. The Line A shows that current flowing through the carbonaceous material 5 of electrode 3 of FIG 2A and 2B is more in respect to the electrode 3 of FIG 3A and 3B . Line B denotes that the electrical current flow through the carbonaceous material 5 of electrode 3 of FIG 3A and 3B is better controlled in respect to the electrode 3 of FIG 2A and FIG 2B.

Claims

Patent Claims
1. A system (1) for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution (2) comprising:
- an electrode (3) comprising a graphite rod (4) and a
carbonaceous material (5) to electrically couple the graphite rod (4) to the carbonaceous material (5) for regulating electric current flow through the carbonaceous material (5) , and
- the aqueous solution (2) comprising the organic
contaminants, the aqueous solution (2) is to the electrode (3) which can generate hydroxyl radicals at a surface (6) of the carbonaceous material (5) and concentrate the organic contaminants onto the surface (6) of the
carbonaceous material (5) , so that the hydroxyl radicals degrade the organic contaminants.
2. The system (1) according to claim 1, wherein the
carbonaceous material (5) comprises at least one of granular activated carbon and activated carbon felt.
3. The system (1) according to any of the claims 1 or 2, wherein the graphite rod (4) is physically coupled to the carbonaceous material (5) so that to provide a physical contact (7) between the graphite rod (4) and the carbonaceous material (5) .
4. The system (1) according to claim 3, wherein the physical contact (7) between the graphite rod (4) and the carbonaceous material (5) is extended up to an entire length (8) of the graphite rod (4) or the mesh cage (9) .
5. The system (1) according to any of the claims from 1 to 4, wherein the electrode (3) comprising a mesh cage (9) adapted to enclose the carbonaceous material (5), the mesh cage (9) comprising an opening (10) to allow the graphite rod (4) into the mesh cage (9) for providing the physical coupling between the graphite rod (4) and the carbonaceous material (5) .
6. The system (1) according to any of the claims 1 to 5, wherein the carbonaceous material (5) is doped with at least one of platinum, boron-doped diamond or a metal oxide.
7. The system (1) according to any of the claims 1 to 6, wherein the aqueous solution (2) comprising an aqueous phase (11) such that the aqueous phase (11) is controlled to avoid physical interaction between the aqueous solution (2) and the graphite rod (4) .
8. The system (1) according to any of the claims 1 to 7, wherein the electrode (3) is having at least one of plane, ring or cylinder geometry.
9 The system (1) according to any of the claims from 1 to 8 comprising :
- a container (12) comprising an inlet (13) for allowing the aqueous solution (2) to enter into the container (12) and an outlet (14) for allowing the aqueous solution (2) to exit after degradation of the organic contaminants,
wherein the electrode (3) is arranged in the container (12) in such a way that the aqueous solution (2) is adapted to be electrochemically coupled to the electrode (3) for degradation of the organic contaminants after entering into the container (12) via the inlet (13) and exit out of the container (12) via the outlet (14) .
10. An electrode (3) for being used in a system (1) for advanced electrochemical oxidation to degrade organic
contaminants in an aqueous solution (2) comprising:
- an electrode (3) comprising a graphite rod (4) and a
carbonaceous material (5) to electrically couple the graphite rod (4) to the carbonaceous material (5) for regulating electric current flow through the carbonaceous material (5), wherein the aqueous solution (2) is adapted to be electrochemically coupled to the electrode (3) which can generate hydroxyl radicals at a surface (6) of the carbonaceous material (5) and concentrate the organic contaminants onto the surface (6) of the carbonaceous material (5) , so that the hydroxyl radicals degrade the organic contaminants electrochemically.
11. The electrode (3) according to claim 10, wherein the graphite rod (4) is physically coupled to the carbonaceous material (5) so that to provide a physical contact (7) between the graphite rod (4) and the carbonaceous material (5) .
12. The electrode (3) according to claim 11, wherein the physical contact (7) between the graphite rod (4) and the carbonaceous material (5) is extended up to an entire length
(8) of the graphite rod (4) .
13. The electrode (3) according to any of the claims 10 to 12, comprising a mesh cage (9) adapted to enclose the
carbonaceous material (5), the mesh cage (9) comprising an opening (10) to allow the graphite rod (4) into the mesh cage
(9) for providing the physical coupling between the graphite rod (4) and the carbonaceous material (5) .
14. The electrode (3) according to any of the claims from 10 to 13, wherein the carbonaceous material (5) is doped with at least one of platinum, boron-doped diamond or a metal oxide.
15. The electrode (3) according to any of the claims from 10 to 14, wherein the electrode (3) is having at least one of plane, ring or cylinder geometry.
PCT/EP2011/051822 2011-02-08 2011-02-08 A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution WO2012107081A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP2011/051822 WO2012107081A1 (en) 2011-02-08 2011-02-08 A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2011/051822 WO2012107081A1 (en) 2011-02-08 2011-02-08 A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution

Publications (1)

Publication Number Publication Date
WO2012107081A1 true WO2012107081A1 (en) 2012-08-16

Family

ID=44625148

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2011/051822 WO2012107081A1 (en) 2011-02-08 2011-02-08 A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution

Country Status (1)

Country Link
WO (1) WO2012107081A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1498355A (en) * 1975-04-30 1978-01-18 Westinghouse Electric Corp Electrolytic process and apparatus for removal of contaminants from water
US4292160A (en) * 1979-08-20 1981-09-29 Kennecott Corporation Apparatus for electrochemical removal of heavy metals such as chromium from dilute wastewater streams using flow-through porous electrodes
EP1036769A1 (en) * 1999-03-17 2000-09-20 Judo Wasseraufbereitung GmbH Apparatus for electrolytic treatment of water or aqueous solutions

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1498355A (en) * 1975-04-30 1978-01-18 Westinghouse Electric Corp Electrolytic process and apparatus for removal of contaminants from water
US4292160A (en) * 1979-08-20 1981-09-29 Kennecott Corporation Apparatus for electrochemical removal of heavy metals such as chromium from dilute wastewater streams using flow-through porous electrodes
EP1036769A1 (en) * 1999-03-17 2000-09-20 Judo Wasseraufbereitung GmbH Apparatus for electrolytic treatment of water or aqueous solutions

Similar Documents

Publication Publication Date Title
US5439577A (en) Electrochemical device for generating hydroxyl free radicals and oxidizing chemical substances dissolved in water
Martínez-Huitle et al. Electrochemical incineration of chloranilic acid using Ti/IrO2, Pb/PbO2 and Si/BDD electrodes
JP4116726B2 (en) Electrochemical treatment method and apparatus
Zanta et al. Electrochemical oxidation of p-chlorophenol on SnO 2–Sb 2 O 5 based anodes for wastewater treatment
US11028491B2 (en) Electrolysis electrode featuring metal-doped nanotube array and methods of manufacture and using same
JP2012228659A (en) Water purification device
KR101825783B1 (en) Photocatalytic Process Integr ated to Microbial Fuel Cell to Treat Pollutants of Wastewater
JP2006256901A (en) Hydrogen production apparatus, hydrogen production method and hydrogen production system
CN102092820A (en) Method and device for removing organic matters from water by using double-pool double-effect visible light in response to photo-electro-Fenton reaction
JP4395768B2 (en) Method and apparatus for generating active oxygen
KR101439953B1 (en) electrode assembly for hydrogen peroxide generation and Electrochemical system for hydrogen peroxide generation
KR20160014763A (en) Membrane electrode assembly and electrolyzed water production device using the same
JP2005230707A (en) Electrochemical reaction method and apparatus
JP2005144240A (en) Electrolytic cell and electrolytic water generator
JP6122978B2 (en) Water purification equipment
JP2012500335A (en) Electrode material, electrode and hydrogen chloride electrolysis
WO2012107081A1 (en) A system and an electrode for being used in the system for advanced electrochemical oxidation to degrade organic contaminants in an aqueous solution
EP3246291A1 (en) Microbial fuel cell system
KR20200110535A (en) A desalination system
JP4146394B2 (en) Water treatment apparatus and water treatment method
KR102631901B1 (en) System for treatment of radioactive decontamination waste water using surface modified particle electrode and method thereof
JP2009131736A (en) Electrolytic unit for water treatment, and electrolytic water treatment device using the same
US8496791B2 (en) Active oxygen generating apparatus
JP4291320B2 (en) Ozone water generator
KR102225397B1 (en) Core-shell catalyst apparatus without moving parts

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11704047

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11704047

Country of ref document: EP

Kind code of ref document: A1