Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82B—NANOSTRUCTURES FORMED BY MANIPULATION OF INDIVIDUAL ATOMS, MOLECULES, OR LIMITED COLLECTIONS OF ATOMS OR MOLECULES AS DISCRETE UNITS; MANUFACTURE OR TREATMENT THEREOF
  • B82B3/00—Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
  • C01G9/00—Compounds of zinc
  • C01G9/02—Oxides; Hydroxides
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K8/00—Cosmetics or similar toiletry preparations
  • A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
  • A61K8/19—Cosmetics or similar toiletry preparations characterised by the composition containing inorganic ingredients
  • A61K8/29—Titanium; Compounds thereof
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61Q—SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS
  • A61Q17/00—Barrier preparations; Preparations brought into direct contact with the skin for affording protection against external influences, e.g. sunlight, X-rays or other harmful rays, corrosive materials, bacteria or insect stings
  • A61Q17/04—Topical preparations for affording protection against sunlight or other radiation; Topical sun tanning preparations
• • 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
  • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J19/0093—Microreactors, e.g. miniaturised or microfabricated reactors
• • 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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y5/00—Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
  • C01B13/14—Methods for preparing oxides or hydroxides in general
  • C01B13/32—Methods for preparing oxides or hydroxides in general by oxidation or hydrolysis of elements or compounds in the liquid or solid state or in non-aqueous solution, e.g. sol-gel process
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
  • C01B13/14—Methods for preparing oxides or hydroxides in general
  • C01B13/32—Methods for preparing oxides or hydroxides in general by oxidation or hydrolysis of elements or compounds in the liquid or solid state or in non-aqueous solution, e.g. sol-gel process
  • C01B13/328—Methods for preparing oxides or hydroxides in general by oxidation or hydrolysis of elements or compounds in the liquid or solid state or in non-aqueous solution, e.g. sol-gel process by processes making use of emulsions, e.g. the kerosine process
• • 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
  • C01G23/053—Producing by wet processes, e.g. hydrolysing titanium salts
• • 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
  • C01G23/053—Producing by wet processes, e.g. hydrolysing titanium salts
  • C01G23/0532—Producing by wet processes, e.g. hydrolysing titanium salts by hydrolysing sulfate-containing salts
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
  • C01G25/00—Compounds of zirconium
  • C01G25/02—Oxides
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/04—Compounds of zinc
  • C09C1/043—Zinc oxide
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/36—Compounds of titanium
  • C09C1/3607—Titanium dioxide
  • C09C1/3669—Treatment with low-molecular organic compounds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
  • C09C3/08—Treatment with low-molecular-weight non-polymer organic compounds
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K2800/00—Properties of cosmetic compositions or active ingredients thereof or formulation aids used therein and process related aspects
  • A61K2800/40—Chemical, physico-chemical or functional or structural properties of particular ingredients
  • A61K2800/41—Particular ingredients further characterized by their size
  • A61K2800/413—Nanosized, i.e. having sizes below 100 nm
• • 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
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00781—Aspects relating to microreactors
  • B01J2219/00889—Mixing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y40/00—Manufacture or treatment of nanostructures
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2004/00—Particle morphology
  • C01P2004/01—Particle morphology depicted by an image
  • C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
• • 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
  • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
• • 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 process for the preparation of (semi-) metal oxides and hydroxides such as SiO 2, TiO 2, ZrO 2, ZnO and other (semi) metal salts such as BaSO 4, which can be prepared by emulsion precipitation from aqueous solution in the form of nanoparticles, and their use ,
• Nanoscale materials have advantageous properties because of their large surface / volume ratio for various technical applications, making them more suitable for various applications than micro- or macroscopic particles of the same chemical compositions. Advantageous applications for these materials are found in virtually all industries.
• nanomaterials for use as fillers or for catalytic processes are particularly advantageous. For example, by nanotechnical improvements already available catalysts supported catalysts with new properties accessible, or a precise control of the catalyst properties is possible.
• the performance of batteries, mini-batteries and electrochemical capacitors can be increased.
• sensors can only be made by the use of nanoparticles. Many oxides can therefore only be used in nanocrystalline form for use as sensor material, for example for chemosensors (eg glucose sensor).
• chemosensors eg glucose sensor
• An example of biosensors are so-called lab on chip systems. Further areas of application are in the field of information processing and transmission in the form of electronic, optical or optoelectronic components.
• nanoscale oxides By introducing nanoscale oxides in various materials essential material properties such. As hardness, wear resistance, etc. can be specifically improved. Many structural applications of nanocrystalline particles result from a targeted distribution of nanoparticles in a ceramic, metallic or Polymer matrix.
• the mechanical properties of metals can be improved, for example, by introducing nanoscale particles, which at the same time makes a significant contribution to lightweight construction.
• Nanoparticulate polymers have features intermediate between organic polymers and inorganic ceramics.
• Nanoscale materials Another important application of nanoscale materials is in cosmetics. Titanium or zinc oxide particles on the nanoscale are used, for example, in sunscreens. Sunscreen products containing nanoparticles show, according to current knowledge, higher efficiencies and better skin compatibility than conventional products.
• Oxides in the form of nanoparticles usually can not be produced by grinding macroscopic particles, but the production process for these materials must already be designed for the production of these smallest particles, since the particles produced must have relative diameters of less than 100 nm.
• Processes developed for this purpose are modifications of already known processes for the production of powder materials, such as e.g. As the flame pyrolysis, precipitation from dilute solutions or corresponding electrochemical processes.
• WO 03/014011 A1 describes a solvopyrolytic process for the preparation of nanoscale, divalent metal oxides, which is carried out at relatively low temperature without additional oxygen using a special precursor.
• compounds of the general formula RMOR ' wherein M is beryllium, zinc, magnesium or cadmium and R and R' independently represent alkyl groups having 1-5 C-atoms, in a suitable solvent in the presence of an inert atmosphere at a temperature lower pyrolyzed as 300 0 C. Agglomerate formation is prevented by addition of a special complexing agent which is absorbed on the surface of the nanoparticles formed.
• GB 2 377 661 A describes a process for the production of nanoparticles, wherein the formation of the particles takes place from a solution on a rotating surface. By adjusting the viscosity of the liquid used and by the crystallization on the surface of the rotating surface, particle agglomeration is avoided.
• Solvents must be disposed of or worked up.
• Object of the present invention is therefore to provide an inexpensive and easy to carry out process for the production of nanoscale metal oxides available that can be operated continuously and under
• the object of the present invention is achieved by emulsifying an aqueous solution of a suitable starting material in a water-immiscible solvent with the aid of a special emulsifier or emulsifier mixture in a micromixer. By adding a suitable reactant to the resulting emulsion, the desired particles are formed therein.
• the solution of the present object is achieved by a process for the preparation of (semi) metal oxides and hydroxides such as SiO 2 , TiO 2 , ZrO 2 , ZnO and other (semi) metal salts such as BaSO 4 , in the form of nanoparticles with a narrow size distribution in the range from 1 nm to 1 .mu.m, in particular from 10 to 200 nm, by a) emulsifying a starting material-containing aqueous solution by intensive mixing in a microreactor with an emulsifier-containing organic solution, b) the emulsion obtained in a reaction solution, the c) the reactant contained in the reaction solution interacts with the reactant-containing aqueous droplets and reacts with the reactant with particle formation and d) the nanoparticles formed are isolated by removal of the solvent.
• (semi) metal oxides and hydroxides such as SiO 2 , TiO 2 , ZrO 2 , Zn
• an aqueous phase is mixed with an emulsifier-containing organic solution in a volume ratio ranging between 1:20 and 1: 1, preferably between 1:10 and 1: 2, the emulsifier being in the organic solvent or Solvent mixture is contained in an amount in the range of 0.5 to 4% by mass.
• the required emulsifier-containing organic solution can be used as the organic solvent aliphatic, cycloaliphatic and aromatic hydrocarbons, heteroaliphatic, heteroaromatic or partially or fully halogenated solvents which form a two-phase system with water.
• a solvent from the group of octane, cyclohexane, benzene, xylene and ethyl ether can be used individually or in admixture for this purpose.
• the educt is present in the aqueous solution in an amount in the range of 25-45% of the mass fraction of its solubility in water
• At least one water-miscible solvent from the group of methyl or ethyl alcohol, acetone, dimethylformamide,
• water-soluble salts of the (Hal) metals Ti, Zn, Zr, Si and Ba in particular salts from the group of the water-soluble salts TiCl 4 , TiOCl 2 , Zn (OAc) 2 , ZrOCl 2 and BaSO 4 , can be used for the production of nanoscale metal oxides according to the improved method.
• the present invention also provides the use of the produced oxidic nanoparticles according to claims 11 to 13 as X-ray or UV absorbers or UV filters with new and improved properties.
• the emulsion After the emulsion has been formed, it may be mixed with an organic solution in which the reactants are contained in a stoichiometric ratio, or the aqueous emulsion containing the starting material may be introduced into an organic solution in which the reactant is in excess.
• Reactants are acids or bases used, which lead to the formation of the corresponding products.
• TiO 2 from TiOCl 2 or TiO (SO 4 )
• SO 4 TiO
• pyridine or methoxyethylamine can be used
• SiO 2 from soda waterglass
• an organic acid from the group acetic acid Propionic acid and butyric acid is suitable.
• Neither the enumeration of the bases nor of the acids is exhaustive.
• the choice of the corresponding reaction partner is made on the basis of the knowledge of the skilled person, who makes the choice on the basis according to the well-known precipitation reactions.
• emulsions with the aid of so-called microemulsions is known from the literature.
• the emulsion forms spontaneously and thermodynamically controlled.
• a feature of this method is the relatively low mass concentration of product, i. H. of less than 1%, and the high amount of emulsifier, which can be several times the content of product.
• the synthesis is carried out by preparing crystalline particles from a stabilized emulsion in one process step.
• suitable emulsifiers are used, which stabilize the Edukttröpfchen to the oxide by reaction is formed with a suitable precipitation reagent. These emulsifiers simultaneously prevent agglomeration of the particles in the emulsion.
• the required emulsions are generated in situ in the microreactor used and need not be prepared in advance in a suitable reactor.
• organic solvents such as aliphatic, cycloaliphatic and aromatic aromatic hydrocarbons and heteroaliphatic and aromatic are suitable. Also, partially or fully halogenated solvents are usable.
• the prerequisite for the applicability of the solvent as a continuous phase is that it forms a two-phase system with water. Particularly suitable for this purpose are toluene, petroleum ether of different boiling ranges and cyclohexane.
• Suitable emulsifiers are those which have a low HLB value and are capable of stabilizing water-in-oil emulsions.
• suitable emulsifiers suitable for this purpose are listed in the following table:
• Preferred emulsifiers are sorbitan monooleate, which is commercially available under the name Span 80, and Lutensol TO3 (BASF).
• the starting materials used correspond to those with which it is possible to precipitate the corresponding oxides from aqueous solution.
• Ti, Zn, Si oxide or BaSO 4 particles can be prepared, for example, by the following chemical reactions in the emulsion droplets formed:
• the preparation of corresponding nanoparticles by the process according to the invention is not limited to these chemical reactions and can also be carried out in another suitable reaction.
• the method according to the invention influences the reaction and the particle formation in such a way that it predetermines a closed reaction space due to the emulsion droplets formed and thus determines the size of the resulting particles.
• the reactions occurring in the droplets correspond to those which occur in a precipitation in would run a single-phase, aqueous system, but with the difference that the reaction is limited here to the volume of the individual drops.
• the mass fraction of the respective salt depends on its solubility and is typically between 25 and 45%.
• water-miscible organic solvents such as methyl or ethyl alcohol, acetone, dimethylformamide, dimethylacetamide or dimethyl sulfoxide may be included in this aqueous solution. It is essential here that this organic solvent is miscible only with the aqueous phase but not with the organic phase used to form the emulsion or the continuous phase.
• a solution of the emulsifier and any co-emulsifiers is prepared in an organic solvent, which is to be used as a continuous phase. Suitable for the preparation of the continuous phase, water-immiscible organic solvents are, for.
• octane cyclohexane, benzene, xylene or ethyl ether.
• various water-immiscible organic solvents are preferred for preparing the emulsion.
• an emulsifier solution is prepared in which the emulsifier is contained in an amount in the range of 0.5 to 4% by mass. Both solutions are mixed and emulsified continuously in the micromixer, wherein the ratio of the aqueous phase to the continuous phase is between 1:20 and 1: 1, preferably between 1:10 and 1: 2. After the aqueous solution of the starting compound has been emulsified, the reaction takes place to the end product either by continuous addition and mixing of a solution of the reactant (base, acid, etc. according to the above table) in the stoichiometric ratio or by introducing the educt emulsion into an excess reactant.
• the reactant base, acid, etc. according to the above table
• the emulsifier stabilizes even after the reaction, the resulting particles and prevents their agglomeration.
• the water-soluble By-products of the reactions can then be washed out, the insoluble nanoparticles remain behind.
• static micromixers are suitable in which the introduced reaction liquids are intensively mixed.
• the intensive mixing can by the
• micromixers in which the liquids are forcibly mixed by the guidance of the flow stream. This can be done in static mixers with thin lines with continuously changing cross sections or more preferably in mixers with intersecting lines. High shear forces are exposed to the liquids, for example in micromixers, in which the educt solutions are combined in thin lines at an angle of 30 to 150 ° or in a T-piece.
• micromixers are suitable in which the liquid streams in thin channels are repeatedly separated and reunited, d. H.
• suitable static micromixers are not only those constructed of interconnected plates with thin channel grooves and openings in the facing surfaces, but also micromixers consisting of a plurality of micromixers of interconnected thin, perforated and optionally structured metal disks are constructed such that the micromixer body constructed in this way has a plurality of thin lines inside which intensively introduced liquids are mixed with each other
• intersecting liquid streams are generated by means of special internals so that an emulsion formation takes place.
• Suitable micromixers are in particular in the patent applications DE 1 95 11 603 A1, WO 95 / 30475A1, WO 01/43857 A1, DE 1 99 27 556 A1 and
• WO 00/76648 A1 or also in A. van den Berg and P. Bergveld (eds.), Micro Total Analysis Systems, 237-243 (1995) Kluwer Academic Publishers, Netherlands.
• the mixer types described in the cited, and as part of, the disclosure of this application correspond to the types described above.
• a suitable one of the commercially available micromixers is selected, which corresponds to one of the types described above and can be used for the preparation of emulsions.
• micromixers of the "split-and-recombine" type are used for this purpose.
• a thin residence in the form of a thin flow channel, which has the same diameter as possible, as the thin mixing channels of the micromixer.
• the emulsion droplets in which the starting materials ausreagierenden to the desired particles are entrapped in a immiscible solution, controlled in a subsequent reaction volume containing an organic, water-immiscible solvent and the other reactants, collected and directly at be reacted, a suitable, constant, set temperature.
• replicable controlled particles are obtained with almost identical properties and constant size distribution.
• the process according to the invention furthermore has the advantage that it is possible to work continuously. If large quantities of corresponding products have to be produced, any number of micromixers can be operated parallel to one another, parallel to one another in a single system or in separately operated systems.
• the desired solid particles in the process according to the invention are formed only after leaving the micromixer and the optionally associated residence zone by reaction in the subsequent reaction volume.
• the method according to the invention therefore avoids the disadvantages of hitherto known methods for producing nanoparticles, in particular of Ti, Zn, Si oxide or BaSO 4 particles, and it has become possible to produce corresponding nanoparticles reproducibly with a narrow particle size distribution and constant Produce controlled properties using inexpensive means, making it continuous and reproducible
• Particles having a particle size in the range of 1 nm - 1 .mu.m, in particular from 10 to 200 nm can be provided.
• the particle size can be shifted downwards or upwards.
• the mixing potential of the mixer in turn depends on its internal structure and the internal dimensions of the channels forming the mixer.
• the micromixer used may be a temperature-controlled type.
• thermocouple For temperature control of the micromixer can be firmly connected to a thermocouple. With a suitable design, however, it is also possible to surround the micromixer reversibly with a temperature control medium or to circulate it, to immerse it in a temperature control bath or to heat it by infrared radiation. In order to obtain reproducible results, however, a reliable, controllable temperature control is necessary.
• WO 02/43853 A1 discloses a suitable tempering device.
• Micromixers which can be used to carry out the process according to the invention must consist of materials which are inert to the reaction media. Micromixers made of glass, silicon, metal or a suitable alloy are suitable. Corresponding micromixers can also consist of suitable oxides, such as silicon oxide, or of a plastic, such as polyolefin, polyvinyl chloride, polyamide, polyester, fluorescene or Teflon. Advantageously, there are also any existing dwell and all devices with which the Reaction solutions and emulsions come into contact with appropriate materials.
• the educt-containing, aqueous solution and the emulsifier-containing organic solution from the separate storage containers are pumped by means of suitable pumps continuously through thin, connected to the input channels in the micro-reactor (s).
• suitable pumps are those pumps with which continuously small quantities of liquid can be conveyed evenly against an increasing pressure. In particular, such pumps are preferred with which the small amounts of liquid can be promoted as possible pulsation.
• Such pumps are commercially available in various embodiments and z. B. also sold as injection syringe pumps. Depending on the desired implementation, these pumps can be operated with different flow rates.
• a solution of titanyl sulphate (15% in dilute sulfuric acid, Aldrich) is provided in a container.
• a solution of Span 80 (Fluka) and Lutensol TO3 (BASF) in cyclohexane is prepared. Both solutions are passed from the reservoirs by means of gear pumps through a micromixer, as described in the patent applications DE 1 95 11 603 A1.
• the micromixer used works according to the "split and Corresponding micromixers are currently marketed by the Institute of Micromechanics Mainz under the name Carterpillarmischer.)
• the volume flows are selected so that they are in a ratio of 1: 5 in relation to the aqueous and organic phases, forming an emulsion from the educt solutions
• the emulsion obtained is passed through a thin line directly into a solution consisting of 60% by weight of cyclohexane and 40% by weight of methoxyethylamine.
• uniform titanium oxide particles having a specific diameter are formed of about 30-70 nm.
• the product formed is stabilized after removal of the solvent from the surface-bound emulsifier and is redispersible in suitable solvent centers (cyclohexane, toluene, petroleum ether).
• Particles redispersed in toluene were examined by scanning electron microscopy. This showed a particle size between 30 and 60 nm (FIG. 1).
• the resulting particles have a diameter of 80-120 nm and are also redispersible in organic solvents.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Inorganic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Health & Medical Sciences (AREA)
• Nanotechnology (AREA)
• General Health & Medical Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Environmental & Geological Engineering (AREA)
• Geology (AREA)
• Veterinary Medicine (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Public Health (AREA)
• Animal Behavior & Ethology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Pharmacology & Pharmacy (AREA)
• Birds (AREA)
• Materials Engineering (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Biophysics (AREA)
• Biotechnology (AREA)
• General Engineering & Computer Science (AREA)
• Medical Informatics (AREA)
• Medicinal Chemistry (AREA)
• Molecular Biology (AREA)
• Epidemiology (AREA)
• Dermatology (AREA)
• Physics & Mathematics (AREA)
• Composite Materials (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• General Physics & Mathematics (AREA)
• Inorganic Compounds Of Heavy Metals (AREA)
• Manufacturing & Machinery (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Oxygen, Ozone, And Oxides In General (AREA)
• Emulsifying, Dispersing, Foam-Producing Or Wetting Agents (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=35759162

Family Applications (1)

Country Status (9)

Families Citing this family (7)

Family Cites Families (9)

• 2004
  • 2004-12-09 DE DE102004059210A patent/DE102004059210A1/de not_active Withdrawn
• 2005
  • 2005-11-11 CA CA002591293A patent/CA2591293A1/en not_active Abandoned
  • 2005-11-11 CN CNA2005800420524A patent/CN101072726A/zh active Pending
  • 2005-11-11 EP EP05812208A patent/EP1831103A1/de not_active Withdrawn
  • 2005-11-11 KR KR1020077012778A patent/KR20070087597A/ko not_active Application Discontinuation
  • 2005-11-11 WO PCT/EP2005/012105 patent/WO2006061078A1/de active Application Filing
  • 2005-11-11 JP JP2007544755A patent/JP2008522934A/ja active Pending
  • 2005-11-11 US US11/721,265 patent/US20090238747A1/en not_active Abandoned
  • 2005-12-07 TW TW094143212A patent/TW200628408A/zh unknown

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events