EP2485838A2 - Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur - Google Patents

Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur

Info

Publication number
EP2485838A2
EP2485838A2 EP10807495A EP10807495A EP2485838A2 EP 2485838 A2 EP2485838 A2 EP 2485838A2 EP 10807495 A EP10807495 A EP 10807495A EP 10807495 A EP10807495 A EP 10807495A EP 2485838 A2 EP2485838 A2 EP 2485838A2
Authority
EP
European Patent Office
Prior art keywords
titanium oxide
copper ion
modified
modified titanium
mass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10807495A
Other languages
German (de)
English (en)
Inventor
Kazuhito Hashimoto
Hiroshi Irie
Yasuhiro Hosogi
Yasushi Kuroda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
University of Tokyo NUC
Resonac Holdings Corp
Original Assignee
Showa Denko KK
University of Tokyo NUC
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 Showa Denko KK, University of Tokyo NUC filed Critical Showa Denko KK
Publication of EP2485838A2 publication Critical patent/EP2485838A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
    • B01J21/063—Titanium; Oxides or hydroxides thereof
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/72—Copper
    • B01J35/30—
    • B01J35/39—
    • B01J35/393—
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • B01J37/033—Using Hydrolysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • C01G23/047—Titanium dioxide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/77—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by unit-cell parameters, atom positions or structure diagrams
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Definitions

  • the present invention relates to a copper ion-modified titanium oxide which is suitable as a photocatalyst capable of exhibiting an activity by irradiation with a visible light and a process for producing the copper ion-modified titanium oxide, and further to a photocatalyst containing the copper ion-modified titanium oxide as a main component.
  • Titanium oxide is widely known as a photocatalyst, but exhibits no photocatalytic function unless it is used in a place where any ultraviolet rays are present. Therefore, at present, it has been attempted to impart a visible light absorbing property to titanium oxide.
  • One of the attempts for imparting a visible light absorbing property to titanium oxide is a method of doping a copper ion into titanium oxide.
  • a composite substance composed of the copper ion and titanium oxide is capable of exhibiting a photocatalytic activity under the irradiation with a visible light (for instance, refer to Patent Document l).
  • Patent Document l Japanese Patent Document 1
  • Non-Patent Document 1 has reported that titanium oxide modified with a copper ion is imparted with a visible light absorption band and a multi-electron reduction capability owing to an interfacial charge transfer so as to decompose isopropanol under the irradiation with a visible light.
  • study on application to only rutile-type titanium oxide has been made, and the method is therefore not applicable to anatase-type titanium oxide or brookite-type titanium oxide which is generally considered to have a high activity.
  • Patent Document l JP-A 9-192496
  • Patent Document 3 JP-A 6-65012
  • Non-Patent Document 1 Hiroshi IRIE, Shuhei MIURA, Kazuhide KAMIYA and Kazuhito HASHIMOTO, "Chemical Physics Letters", 457 (2008), pp. 202-205
  • an object of the present invention is to provide a copper ion-modified titanium oxide which is capable of exhibiting a good catalytic activity under the irradiation with a visible light when used as a photocatalyst, a process for producing the copper ion-modified titanium oxide, and a photocatalyst containing the copper ion-modified titanium oxide as a main component.
  • the present inventors have found that the above conventional problems can be solved by the following aspects of the present invention. That is, the present invention relates to the following aspects.
  • a copper ion-modified titanium oxide including titanium oxide whose surface is modified with a copper ion, and containing a brookite-type crystal.
  • a process for producing a copper ion-modified titanium oxide including: a hydrolysis step of subjecting a titanium compound capable of producing titanium oxide to hydrolysis in a reaction solution! and
  • a copper ion-modified titanium oxide which is capable of exhibiting a good catalytic activity under the irradiation with a visible light when used as a photocatalyst, a process for producing the copper ion-modified titanium oxide, and a
  • photocatalyst containing the copper ion-modified titanium oxide as a main component photocatalyst containing the copper ion-modified titanium oxide as a main component.
  • FIG. 1 is a view showing an X-ray diffraction pattern of the copper ion-modified titanium oxide obtained in Example 1.
  • the copper ion-modified titanium oxide of the present invention has a crystal structure at least a part of which is composed of a brookite-type crystal.
  • the copper ion- modified titanium oxide may also include hydrous titanium oxide, titanium hydroxide, titanic acid, an amorphous moiety, an anatase-type crystal, a rutile-type crystal, etc., as long as it contains the brookite-type crystal.
  • the presence of the brookite-type crystal in the copper ion-modified titanium oxide may be determined by powder X-ray diffraction using a Cu-Kal ray. More specifically, the presence of the brookite-type crystal is determined by satisfying the condition that in a lattice spacing d (A) as measured in the powder X-ray diffraction, a diffraction line is detected at least in the range of 2.90 ⁇ 0.02 A.
  • the content of the brookite-type crystal in the copper ion-modified titanium oxide can be measured by Rietveld analysis in which the titanium oxide is mixed with 10% by mass of nickel oxide as an internal standard substance.
  • the proportions of the respective crystal phases being present in the titanium oxide may be determined using a Rietveld analytical software in a program " ⁇ ' Pert High Score Plus" available from Panalytical Co., Ltd.
  • the content of the brookite-type crystal in the copper ion-modified titanium oxide is preferably not less than 14% by mass and not more than 60% by mass, and more preferably not less than 14% by mass and not more than 40% by mass.
  • the content of the brookite-type crystal of not less than 14% by mass is preferable because a dispersibility of the titanium oxide sol as well as an absorption of the copper ion into titanium oxide can be enhanced.
  • the copper ion-modified titanium oxide having a brookite-type crystal content of not less than 14% by mass can exhibit an excellent catalyst performance when used as a photocatalyst.
  • the content of the brookite-type crystal is not more than 60% by mass, the copper ion-modified titanium oxide is inhibited from exhibiting an excessively large crystallite size, so that the titanium oxide and the copper ion used for modifying the surface of the titanium oxide can maintain a good interaction therebetween.
  • the crystallite size of the brookite-type crystal is preferably 24 nm or less, more preferably 18 nm or less, still more preferably from 5 to 18 nm, further still more preferably from 5 to 12 nm, and most preferably from 9 to 12 nm.
  • the crystallite size of the brookite-type crystal is 24 nm or less, the interaction between the brookite-type crystal and the copper ion can be suitably improved, and further the resulting photocatalyst can exhibit a high visible light activity owing to occurrence of change in reactivity between the surface of the respective photocatalyst particles and the copper ion.
  • the crystallite size of the crystal can be calculated from the following Scherrer's formula wherein t represents a crystallite size (nm); ⁇ represents a wavelength (A) of X-ray BM represents a half value width of a sample; Bs represents a half value width of a reference (S1O2); and ⁇ represents a diffraction angle.
  • the surface of the titanium oxide is modified with the copper ion.
  • the copper ion include those derived from copper (II) chloride, copper (II) acetate, copper (II) sulfate, copper (II) nitrate, copper (II) fluoride, copper (II) iodide, copper (II) bromide, etc. Among them, from the viewpoints of a good
  • the copper ion derived from copper (II) chloride is preferred.
  • the copper ion is produced by subjecting the above precursor to chemical reactions such as decomposition and oxidation on the titanium oxide, or through physical change of the precursor such as precipitation, etc.
  • the amount of the copper ion used for modifying the titanium oxide is preferably from 0.05 to 0.3% by mass and more preferably from 0.1 to 0.2% by mass in terms of metallic copper (Cu) on the basis of the titanium oxide.
  • the amount of the copper ion used for the modification is 0.05% by mass or more, the resulting photocatalyst can exhibit a good photocatalytic performance.
  • the amount of the copper ion used for the modification is 0.3% by mass or less, the copper ion tends to be hardly aggregated together, so that the resulting photocatalyst can be prevented from undergoing
  • Non-Patent Document 1 The mechanism of the interaction between the copper ion and the rutile-type titanium oxide is described in the above Non-Patent Document 1 as follows, although it is not clearly known yet.
  • the above-mentioned mechanism is also applicable to the titanium oxide containing the brookite-type crystal having a smaller crystallite size according to the present invention. That is, according to the above mechanism, the titanium oxide containing the brookite-type crystal can be imparted with a high visible light-responsive property and further can be promoted in interaction with the copper ion owing to the difference in crystal structure therebetween, and as a result, can exhibit a more excellent photocatalytic activity than that of the conventional titanium oxides.
  • the two kinds of crystals i.e., the anatase-type crystal and the rutile-type crystal which are different in band gap from the brookite-type crystal
  • the two kinds of crystals i.e., the anatase-type crystal and the rutile-type crystal which are different in band gap from the brookite-type crystal
  • the charge separation between the electrons and holes can be promoted, which makes a large contribution to excellent properties of the brookite-type crystal-containing titanium oxide according to the present invention.
  • the process for producing a copper ion-modified titanium oxide according to the present invention includes a hydrolysis step of subjecting a titanium compound capable of producing titanium oxide to hydrolysis in a reaction solution? and a surface modification step of mixing a solution obtained after the hydrolysis with an aqueous solution containing a copper ion to modify a surface of the titanium oxide therewith.
  • an aqueous solution of a titanium compound capable of producing titanium oxide such as, for example, titanium chloride
  • a titanium compound capable of producing titanium oxide such as, for example, titanium chloride
  • the thus produced titanium oxide may have an optional crystal shape by varying conditions of the solution used upon the hydrolysis.
  • titanium oxide particles having a brookite content of from 7 to 60% by mass may be produced.
  • the crystal structure or crystallite size of the titanium oxide has a large influence on a mobility of a carrier produced by irradiation with light as well as on an interaction with the copper ion.
  • the rutile-type titanium oxide tends to be produced when the hydrolysis is carried out at a temperature of 80°C or lower.
  • the anatase-type titanium oxide tends to be produced when the hydrolysis is carried out at a temperature of from 80 to 90°C.
  • the brookite-type titanium oxide tends to be produced when the hydrolysis is carried out at a temperature of 95°C.
  • titanium compound examples include titanium tetrachloride, titanium trichloride, titanium sulfate, titanium tetraethoxide and titanium tetraisopropoxide.
  • titanium tetrachloride preferred are titanium tetrachloride and titanium trichloride.
  • the temperature of the reaction solution used upon the hydrolysis is preferably not lower than 70°C and not higher than a boiling point of the reaction solution.
  • reaction solution is preferably bubbled with oxygen or ozone to well control a crystal structure and crystallite size of the resulting titanium oxide.
  • the temperature used for the surface modification is preferably controlled to the range of from 80 to 95°C and more preferably from 90 to 95°C.
  • the surface modification temperature is controlled to the range of from 80 to 95°C, the surface of the titanium oxide can be modified with the copper ion in an efficient manner.
  • the surface modification with the copper ion may be carried out according to the method described in the above Non-Patent Document 1.
  • a method in which titanium oxide particles and copper chloride are mixed with each other in a suitable medium under heating, and then the resulting reaction mixture is washed with water to recover the aimed product (2) a method in which titanium oxide particles and copper chloride are mixed with each other in a suitable medium under heating, and then the resulting reaction mixture is subjected to evaporation to dryness to recover the aimed product, or the like.
  • the method (l) is preferred because counter anions can be removed from the reaction mixture without heat treatment.
  • the surface of the respective titanium oxide particles is modified with the copper ion.
  • the condition of the presence of the copper ion used for modifying the surface of the titanium oxide is hardly analyzed owing to a trace amount of the copper ion. For this reason, when subjecting the titanium oxide to diffused reflection spectrum analysis using an
  • any absorption band attributed to neither only titanium oxide nor only the copper ion is observed near the range of from 420 to 500 nm, it is deemed that such a case is involved in modification with the copper ion.
  • the properties and quantity of the copper ion may also be determined by ICP analysis.
  • the photocatalyst of the present invention contains the copper ion-modified titanium oxide as a main component.
  • the content of the copper ion-modified titanium oxide in the photocatalyst is 70% by mass or more and preferably 75% by mass or more on the basis of a total amount of the photocatalyst.
  • photocatalyst include amorphous titanium oxide and hydrous titanium oxide.
  • the photocatalyst of the present invention may be used with various shapes. However, the photocatalyst is preferably used in the form of a powder.
  • the photocatalyst of the present invention is capable of exhibiting a photocatalytic performance when irradiated with a light having a wavelength of 420 nm or shorter, but can also exhibit a photocatalytic performance even when irradiated with a light having a wavelength of 420 nm or longer.
  • the photocatalytic performance as used in the present invention may also include other performances such as an antimicrobial property, a
  • deodorizing property an anti-fouling property and environmental purification properties such as atmospheric purification property and water purification property.
  • environmental purification properties such as atmospheric purification property and water purification property.
  • the respective copper ion-modified titanium oxides obtained in the following Examples and Comparative Examples were subjected to XRD measurement to identify a crystal structure thereof and to determine proportions of various crystals being present therein as well as a crystallite size of a brookite-type crystal contained therein.
  • the XRD measurement was carried out using copper as a target and Cu-Kocl ray under the following conditions-
  • the apparatus used in the above XRD measurement was "X' pert PRO” available from Panalytical Co., Ltd.
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and 60 g of a titanium trichloride aqueous solution (20% by mass solution! density: 1.23 g/mL) were added dropwise into the reaction vessel at a rate of 1 g/min. Thereafter, while bubbling the contents of the reaction vessel with oxygen supplied through an ozone generator, the temperature in the reaction vessel was raised up to 101°C over 30 min, and then maintained at 101°C for 90 min. The resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4. Into 200 mL of the resulting slurry solution (powder content: 1.5 g) was added 0.5 mL of a copper chloride aqueous solution
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and the distilled water was heated to 95°C and held 10 068223 at the same temperature. Then, 60 g of a titanium tetrachloride aqueous solution (Ti content: 17.0% by mass; specific gravity: 1.52) were added
  • the resulting mixture was heat-treated while stirring at 90°C for 1 h, and then allowed to stand for cooling it to room temperature.
  • the obtained reaction mixture was washed by centrifugal separation to recover a reaction product.
  • the thus recovered reaction product was dried at 120°C for 24 h and then pulverized using an agate mortar, thereby obtaining a hght-yellow copper ion-modified titanium oxide containing 35% by mass of a brookite-type crystal according to the present invention.
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and 60 g of a titanium tetrachloride aqueous solution (Ti content: 17.0% by mass? specific gravity: 1.52) were added dropwise into the reaction vessel at a rate of 1 g/min. Thereafter, the contents of the reaction vessel were heated up to 101°C, and then maintained at 101°C for 120 min. The resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4.
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and the distilled water was heated to 70°C and held at the same temperature. Then, 60 g of a titanium tetrachloride aqueous solution (Ti content: 17.0% by mass; specific gravity: 1.52) were added dropwise into the reaction vessel at a rate of 1 g/min while continuously stirring the contents of the reaction vessel at a rate of 300 rpm. The reaction solution in the reaction vessel began becoming whitely turbid immediately after initiation of the dropping, but was maintained as such at its temperature. After completion of the dropping, the reaction solution was further heated to 75°C and maintained at the same temperature for 60 min.
  • Ti content 17.0% by mass
  • specific gravity specific gravity
  • the resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4.
  • the resulting mixture was heat-treated while stirring at 90°C for 1 h, and then allowed to stand for cooling it to room temperature.
  • the obtained reaction mixture was washed by centrifugal separation to recover a reaction product.
  • the thus recovered reaction product was dried at 120°C for 24 h and then pulverized using an agate mortar, thereby obtaining a light-yellow copper ion-modified titanium oxide containing 14% by mass of a brookite-type crystal.
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and the distilled water was heated to 95°C and held at the same temperature. Then, 60 g of a titanium trichloride aqueous solution (20% by mass solution; density: 1.23 g/mL) were added drop wise into the reaction vessel at a rate of 1 g/min while continuously stirring the contents of the reaction vessel at a rate of 300 rpm and further bubbling the contents of the reaction vessel with oxygen supplied through an ozone generator.
  • the bubbling with oxygen supplied through the ozone generator was terminated, and the reaction solution was maintained as such at its temperature.
  • the reaction solution was further heated to a temperature near a boiling point thereof and maintained at the same temperature for 60 min.
  • the resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4.
  • Into 150 mL of the resulting slurry solution (powder content ⁇ 1.5 g) was added 0.5 mL of a copper chloride aqueous solution
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and the distilled water was heated to 95°C and held at the same temperature. Then, 60 g of a titanium trichloride aqueous solution (20% by mass solution; density: 1.23 g/mL) were added dropwise into the reaction vessel at a rate of 1 g/min while continuously stirring the contents of the reaction vessel at a rate of 300 rpm and further bubbling the contents of the reaction vessel with oxygen supplied through an ozone generator. The resulting reaction solution was maintained at its temperature. After completion of the dropping, the reaction solution was further heated to a temperature near a boiling point thereof and maintained at the same temperature for 60 min.
  • a titanium trichloride aqueous solution (20% by mass solution; density: 1.23 g/mL) were added dropwise into the reaction vessel at a rate of 1 g/min while continuously stirring the contents of the reaction vessel at a rate of 300 rpm and further bubbling the contents of the reaction
  • the resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4.
  • the resulting mixture was heat-treated while stirring at 90°C for 1 h, and then allowed to stand for cooling it to room temperature.
  • the obtained reaction mixture was washed by centrifugal separation to recover a reaction product.
  • the thus recovered reaction product was dried at 120°C for 24 h and then pulverized using an agate mortar, thereby obtaining a light-yellow copper ion-modified titanium oxide containing 60% by mass of a brookite-type crystal according to the present invention.
  • a reaction vessel equipped with a reflux condenser was charged with 690 mL of distilled water, and the distilled water was heated to 80°C and held at the same temperature. Then, 60 g of a titanium tetrachloride aqueous solution (Ti content: 17.0% by mass! specific gravity: 1.52) were added dropwise into the reaction vessel at a rate of 1 g/min while continuously stirring the contents of the reaction vessel at a rate of 300 rpm. The reaction solution in the reaction vessel began becoming whitely turbid immediately after initiation of the dropping, but was maintained as such at its temperature. After completion of the dropping, the reaction solution was heated to 85°C and maintained at the same temperature for 60 min.
  • Ti content 17.0% by mass! specific gravity: 1.52
  • the resulting sol was subjected to dechlorination treatment using an electrodialysis device until a pH value of the sol reached 4.
  • the resulting mixture was heat-treated while stirring at 90°C for 1 h, and then allowed to stand for cooling it to room temperature.
  • the obtained reaction mixture was washed by centrifugal separation to recover a reaction product.
  • the thus recovered reaction product was dried at 120°C for 24 h and then pulverized using an agate mortar, thereby obtaining a copper ion-modified titanium oxide composed of a rutile-type crystal only.
  • a suspension prepared by suspending 1.5 g of a commercially available titanium oxide composed mainly of an anatase-type crystal (tradename
  • a commercially available titanium oxide composed of an anatase-type crystal only (tradename "ST01" available from Ishihara Sangyo Kaisha, Ltd.) was modified with a copper ion in the same manner as in Comparative
  • Example 2 thereby obtaining a copper ion-modified titanium oxide.
  • a glass petri dish having a diameter of 1.5 cm was disposed in a closed-type glass reactor (capacity- 0.5 L), and 0.3 g of the respective titanium oxide particles obtained in the above Examples and Comparative Examples was placed in the petri dish.
  • An inside atmosphere of the reactor was replaced with a mixed gas containing oxygen and nitrogen at a volume ratio of 1-4, and the reactor was charged with 5.2 ⁇ of water (corresponding to a relative humidity of 50% (at 25°C)) and 5.0 mL of 5.1% acetaldehyde (a mixed gas with nitrogen " standard condition ' 25°C, 1 atm) and then sealed, followed by irradiating a visible light from outside of the reactor.
  • the irradiation with a visible light was carried out using a xenon lamp fitted with a filter for cutting an ultraviolet light having a wavelength of 420 nm or less (tradename "Y-44" available from Asahi Techno Glass Co., Ltd.) as a light source.
  • a xenon lamp fitted with a filter for cutting an ultraviolet light having a wavelength of 420 nm or less (tradename "Y-44" available from Asahi Techno Glass Co., Ltd.) as a light source.
  • the rate of reduction in amount of the acetaldehyde as well as the rate of generation of carbon dioxide as an oxidative decomposition product were measured with time by gas chromatography.
  • the true amount of carbon dioxide generated from the acetaldehyde was determined as the value obtained by subtracting the amount of carbon dioxide as measured immediately before the irradiation with a visible light from the amount of carbon dioxide generated as measured after 8 h from initiation of the irradiation with a visible light. The results are shown in Table 1.
  • the amount of carbon dioxide produced using the copper ion-modified titanium oxide containing a brookite-type crystal according to the present invention was from 1.3 to 2.4 times that produced using the copper ion-modified titanium oxide containing no brookite-type crystal. Therefore, it was apparently confirmed that the copper ion-modified titanium oxide according to the present invention was a photocatalyst having a high photocatalytic activity. In the copper ion-modified titanium oxide having a brookite-type crystal content of 40% by mass or less, as the brookite-type crystal content was increased, the photocatalytic activity thereof was enhanced correspondingly.
  • the photocatalytic activity thereof became lowered. That is, when the brookite-type crystal content in the copper ion-modified titanium oxide is not more than 40% by mass, the proportion of the brookite-type crystal particles in the titanium oxide is increased with the increase in the brookite-type crystal content, so that the photocatalytic activity thereof can be improved.
  • the proportion of the brookite-type crystal particles in the titanium oxide is increased with the increase in the brookite-type crystal content, so that the photocatalytic activity thereof can be improved.
  • brookite-type crystal content exceeds 40% by mass, the crystallite size of the brookite-type crystal becomes as large as up to about 20 nm, so that an interaction between the copper ion and the titanium oxide is lessened, resulting in a deteriorated photocatalytic activity of the copper ion-modified titanium oxide.

Abstract

La présente invention porte sur un oxyde de titane modifié par un ion du cuivre comprenant de l'oxyde de titane dont la surface est modifiée par un ion du cuivre et contenant un cristal de type brookite ; sur un procédé de production d'un oxyde de titane modifié par un ion du cuivre, comprenant une étape d'hydrolyse consistant à soumettre un composé du titane permettant de produire de l'oxyde de titane à une hydrolyse dans une solution réactionnelle et une étape de modification de surface consistant à mélanger une solution obtenue après l'hydrolyse avec une solution aqueuse contenant un ion du cuivre pour modifier une surface de l'oxyde de titane avec celui-ci ; et sur un photocatalyseur contenant l'oxyde de titane modifié par un ion du cuivre en une quantité supérieure ou égale à 70 % en masse.
EP10807495A 2009-10-08 2010-10-08 Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur Withdrawn EP2485838A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2009234370A JP2011079713A (ja) 2009-10-08 2009-10-08 銅イオン修飾酸化チタン及びその製造方法、並びに光触媒
PCT/JP2010/068223 WO2011043496A2 (fr) 2009-10-08 2010-10-08 Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur

Publications (1)

Publication Number Publication Date
EP2485838A2 true EP2485838A2 (fr) 2012-08-15

Family

ID=43857238

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10807495A Withdrawn EP2485838A2 (fr) 2009-10-08 2010-10-08 Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur

Country Status (6)

Country Link
EP (1) EP2485838A2 (fr)
JP (1) JP2011079713A (fr)
KR (1) KR20120095855A (fr)
CN (1) CN102574107A (fr)
TW (1) TW201129508A (fr)
WO (1) WO2011043496A2 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103228358B (zh) * 2011-06-27 2015-08-26 昭和电工株式会社 担载有铜化合物的氧化钛光催化剂和其制造方法
JP5655162B2 (ja) 2011-12-15 2015-01-14 堺化学工業株式会社 遷移金属及び／又は遷移金属酸化物を担持した酸化チタンの顆粒体並びに該顆粒体を使用した廃プラスチック・有機物の分解方法
EP2727649A4 (fr) * 2011-12-22 2014-10-08 Showa Denko Kk Composition contenant du cuivre et du titane et son procédé de fabrication
JP6027394B2 (ja) * 2012-10-26 2016-11-16 宝栄産業株式会社 エマルジョンタイプ塗料
MD4294C1 (ro) * 2013-02-06 2015-02-28 Государственный Университет Молд0 Procedeu de obţinere a nanocompozitelor pe bază de nanotuburi din dioxid de titan şi instalaţie pentru realizarea acestuia
US10464055B2 (en) 2014-03-11 2019-11-05 Nitto Denko Corporation Photocatalytic element

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4085193A (en) * 1973-12-12 1978-04-18 Mitsubishi Petrochemical Co. Ltd. Catalytic process for reducing nitrogen oxides to nitrogen
JPH0737363B2 (ja) 1992-08-19 1995-04-26 工業技術院長 抗菌抗カビ性セラミックス及びその製造方法
JPH06205977A (ja) 1992-09-01 1994-07-26 Toto Ltd 光触媒組成物の製造方法及び光触媒組成物
JPH09192496A (ja) 1996-01-12 1997-07-29 Matsushita Electric Works Ltd 光触媒及びそれを備えた自己清浄品
JP2003002646A (ja) * 2001-06-20 2003-01-08 Asahi Kasei Corp 複合酸化チタン分散液
CN1613555A (zh) * 2004-09-28 2005-05-11 北京化工大学 纳米复合光催化剂制备的新工艺
TW200704593A (en) * 2005-04-22 2007-02-01 Dow Corning Toray Co Ltd Solution or dispersion for substarate surface treatment comprising titanium oxide doped with metallic element, method for substrate surface treatment using the same, and surface-treated material obtained therefrom

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011043496A2 *

Also Published As

Publication number Publication date
WO2011043496A3 (fr) 2012-01-05
KR20120095855A (ko) 2012-08-29
CN102574107A (zh) 2012-07-11
JP2011079713A (ja) 2011-04-21
WO2011043496A2 (fr) 2011-04-14
TW201129508A (en) 2011-09-01

Similar Documents

Publication Publication Date Title
Huang et al. Effect of carbon doping on the mesoporous structure of nanocrystalline titanium dioxide and its solar-light-driven photocatalytic degradation of NO x
Moon et al. Preparation and characterization of the Sb-doped TiO2 photocatalysts
Zaleska Doped-TiO2: a review
US9868109B2 (en) Titanate / titania composite nanoparticle
Nilchi et al. Sol-gel preparation of nanoscale TiO2/SiO2 composite for eliminating of Con Red azo dye
US8728973B2 (en) Photocatalytic materials and process for producing the same
WO2009116181A1 (fr) Photocatalyseur sensible à la lumière visible et son procédé de fabrication
WO2003080244A1 (fr) Photocatalyseur oxyde de titane, procede permettant de produire ce photocatalyseur et application
WO2011043496A2 (fr) Oxyde de titane modifié par un ion du cuivre et son procédé de production et photocatalyseur
JP2008260011A (ja) 可視光応答型光触媒とその製造方法
JP3894144B2 (ja) 酸化チタン系光触媒とその製造方法および応用
Ghorai Photocatalytic degradation of 4-chlorophenol by CuMoO 4-doped TiO 2 nanoparticles synthesized by chemical route
US8357348B2 (en) Method for preparing uniform anatase-type titanium dioxide nanoparticles
Ma et al. Synthesis of visible light-driven Eu, N co-doped TiO 2 and the mechanism of the degradation of salicylic acid
JP2004196641A (ja) アナターゼ型結晶組成物およびその製造法
Apiwong-ngarm et al. Photocatalytic activities of Fe–Cu/TiO2 on the mineralization of oxalic acid and formic acid under visible light irradiation
Im et al. Investigation of multielemental catalysts based on decreasing the band gap of titania for enhanced visible light photocatalysis
Gambhire et al. Degradation of methylene blue via photocatalysis of transition metal-loaded sulfated TiO2
Wang et al. Synthesis of triphasic, biphasic, and monophasic TiO 2 nanocrystals and their photocatalytic degradation mechanisms
Ahmed et al. Visible-light-driven photocatalytic formation of propylene carbonate using FeNbO4/reduced graphene oxide composites
Lin et al. Photocatalytic degradation of 1, 2-dichloroethane by V/TiO2: the mechanism of photocatalytic reaction and byproduct
JP4265685B2 (ja) 光触媒体、その製造方法およびそれを用いてなる光触媒体コーティング剤
JP2004344863A (ja) 光触媒担持多孔性ゲル及びその製造法
Zhang et al. Structural characterization and photocatalytic activity of synthesized carbon modified TiO2 for phenol degradation
JP2004161592A (ja) アナターゼ型チタニア−シリカ複合体とその製造法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20120330

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20120801