DE762723C - Process for cleaning finely divided oxides from metals or metalloids - Google Patents

Process for cleaning finely divided oxides from metals or metalloids

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Publication number
DE762723C
DE762723C DED87110D DED0087110D DE762723C DE 762723 C DE762723 C DE 762723C DE D87110 D DED87110 D DE D87110D DE D0087110 D DED0087110 D DE D0087110D DE 762723 C DE762723 C DE 762723C
Authority
DE
Germany
Prior art keywords
oxides
metals
metalloids
subjected
finely divided
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.)
Expired
Application number
DED87110D
Other languages
German (de)
Inventor
Harry Dr Kloepfer
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.)
Evonik Operations GmbH
Original Assignee
Degussa GmbH
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 Degussa GmbH filed Critical Degussa GmbH
Priority to DED87110D priority Critical patent/DE762723C/en
Application granted granted Critical
Publication of DE762723C publication Critical patent/DE762723C/en
Expired legal-status Critical Current

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Classifications

    • 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
    • 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
    • C01B13/145—After-treatment of oxides or hydroxides, e.g. pulverising, drying, decreasing the acidity
    • 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
    • C01B13/20—Methods for preparing oxides or hydroxides in general by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state
    • C01B13/22—Methods for preparing oxides or hydroxides in general by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state of halides or oxyhalides
    • 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
    • C01B13/20—Methods for preparing oxides or hydroxides in general by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state
    • C01B13/22—Methods for preparing oxides or hydroxides in general by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state of halides or oxyhalides
    • C01B13/30—Removal and cooling of the oxide-containing suspension
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/113—Silicon oxides; Hydrates thereof
    • C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
    • C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
    • C01B33/181—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by a dry process
    • C01B33/183—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by a dry process by oxidation or hydrolysis in the vapour phase of silicon compounds such as halides, trichlorosilane, monosilane
    • 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
    • C01G23/07—Producing by vapour phase processes, e.g. halide oxidation
    • 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
    • C01G23/07—Producing by vapour phase processes, e.g. halide oxidation
    • C01G23/075—Evacuation and cooling of the gaseous suspension containing the oxide; Desacidification and elimination of gases occluded in the separated 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
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/04—Physical treatment, e.g. grinding, treatment with ultrasonic vibrations
    • C09C3/043—Drying, calcination
    • 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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/80—Compositional purity

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Nanotechnology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Composite Materials (AREA)
  • Physics & Mathematics (AREA)
  • Treating Waste Gases (AREA)

Description

Gegenstand der vorliegenden Erfindung ist die Reinigung· hochdisperser Oxyde von Metallen t>zvv^Metalloklen, die durch thermische Zersetzung von Verbindungen dieser Metalle l)zw. Metalloide in dampfförmigem Zustand in Gegenwart oxydierend bzw. hydrolysiereiid wirkender Gase oder Dämpfe IxH höheren Temperaturen erhalten werden, wobei die abgeschiedenen Oxyde einer Wärmel>ehandluiig l>ei Temperaturen von etwa 200 bis etwa 500°, also unterhalb Rotglut, gegebenenfalls in strömenden gas- oder dampfförmigen MedienThe subject of the present invention is the purification of highly disperse oxides from metals t> zvv ^ metal cycles caused by thermal Decomposition of compounds of these metals l) betw. Metalloids in a vaporous state in the presence of oxidizing or hydrolysing gases or vapors IxH higher Temperatures can be obtained, with the deposited oxides of a heat barrier l> ei temperatures of about 200 to about 500 °, i.e. below red heat, possibly in flowing gaseous or vaporous media

so lange unterworfen werden, bis die von Zersetzung- stammenden Yerunreinigui ganz oder weitgehend entfernt sind.be subjected until the decomposition-derived Yerzinigui are completely or largely removed.

Die thermische Zersetzung erfolgt in kannter Weise vermittels Durchleiten der zusetzenden Gase oder Dämpfe durch crh Zonen, durch Flammen, durch elektrj Lichtl>ogeri Qxlm. Funken- "oder GfimnThe thermal decomposition is carried out in known manner by means of passing the gases or vapors by clogging crh zones, by flame, thr ough e lektrj Lichtl> ogeri Qxlm. Spark "or Gfimn

ladungen.charges.

Die hierbei gebildeten feinverteilten O: können- in beliebiger Weise aufgefangen gesammelt werden, ■/.. V>. vermittels L-The finely divided O: formed in this way can be collected in any way desired, ■ / .. V>. by means of L-

beliebiger Art nach !.«.'kannten Methoden der elektrischen Staubabscheidungen, ζ. 15. System Siemens-Cottrell. Besonders hochdisperse Oxyde werden erhalten, wenn man die Uxyde nach einem eigenen, nicht vorveröffentlichten Vorschlag noch in der Zersetzungszone auf l>ewegten Flächen oljerhalb des Taupunktes des Wassers bzw. der Salzsäure oder anderer leicht kondensierbarer dampfförmiger Reaktionsprodukte abscheidet und die abgeschiedenen Oxydteile durch Abstreifen vor dem nochmaligen Hindurchführen durch die Zersetzungszone schützt. Obwohl in letzterem Falle die Abscheidung der feinverteilten Oxyde bei solchen Tem{>eraturen vorgenommen wird, daß unerwünschte Kondensationen der bei der Umsetzung entstandenen Produkte, wie z. B. von Wasser oder wäßriger Salzsäure, vermieden werden, enthalten auch ι die derart gewonnenen Produkte noch Beimengungen je nach der Art der verwendeten Ausgangsprodukte und der thermischen Oxydation bzw. Hydrolyse. Benutzt man als Ausgangsmaterial z. B. Siliciumtetrachlorid, so erhält man ein Produkt, welche? entsprechend dem hohen Adsorptionsvermögen des entstandenen Kieselsäureaerosols noch reichliche Mengen Chlorwasserstoff hartnäckig festhält. Dieser Salzsäuregehalt macht aber das Pro-D dukt für die meisten Verwendungszwecke wertlos. Xun besitzen die erhaltenen hochdispersen Produkte ein außerordentlich hohes Reagglomerierungsbestrel>en, welches sich besonders l>ei erhöhten Temperaturen l>emerkbar macht. Trotzdem gelingt es. erfindungsgemäß praktisch reine Produkte zu erhalten, wenn man gemäß der vorliegenden Erfindung die hochdis{>ersen Oxyde gegetxmenfalls unmittelbar nach ihrer Abscheidung einer ο Wärmebehandlung l>ei Temperaturen von etwa 2OO bis etwa 5003, also unterhalb Rotglut, die ia bekanntlich l>ei den Oxyden bei etwa 550" beginnt, unterwirft.of any kind according to!. «. 'knew methods of electrical dust separation, ζ. 15. Siemens-Cottrell system. Particularly highly disperse oxides are obtained if, according to a proprietary, unpublished proposal, the oxides are deposited in the decomposition zone on clear surfaces above the dew point of the water or hydrochloric acid or other easily condensable vaporous reaction products and the deposited oxide parts by stripping off before the again passing through the decomposition zone protects. Although in the latter case the deposition of the finely divided oxides is carried out at such temperatures that undesired condensation of the products formed during the reaction, such as. B. of water or aqueous hydrochloric acid are avoided, the products obtained in this way also contain additions depending on the type of starting products used and the thermal oxidation or hydrolysis. If you use z as the starting material. B. silicon tetrachloride, one obtains a product, which one? stubbornly holds on to copious amounts of hydrogen chloride in accordance with the high adsorption capacity of the resulting silica aerosol. However, this hydrochloric acid content makes the product worthless for most purposes. The highly disperse products obtained have an extraordinarily high level of reagglomeration, which is particularly noticeable at elevated temperatures. Nevertheless it works. According to the invention, practically pure products can be obtained if, according to the present invention, the highly dispersed oxides, if necessary immediately after their deposition, are subjected to a heat treatment at temperatures of about 2OO to about 500 3 , i.e. below red heat, which is generally known to be Oxides starts at around 550 ", subjects.

Es ist zwar l>ei der Pigmentherstellung, z. B. l>eim Zinkweiß, schon l>ekannt, dieses nachzuglühen. Hierbei werden jedoch höhere Temperaturen von mindestens 6oo° angewendet, die im vorliegenden Falle schon zu einer Aggloiherierung der einzelnen Teilchen und ο dadurch l>edingten Korn vergröl >erung führen würden, was erfindungsgemäß unl>edingt zu vermeiden ist.It is true that it is the production of pigments, e.g. B. l> eim zinc white, already l> e known, this one to glow afterwards. Here, however, higher temperatures of at least 600 ° are used, which in the present case already lead to an agglomeration of the individual particles and ο this would lead to increased grain size, which according to the invention is essential avoid is.

Es empfiehlt sich, die WärmelK-handlung in Gegenwart von Dämpfen und Gasen, wie z. B. Luft, Wasserdampf, Stickstoff. (Jeneratorgas u. dgl., vorzunehmen. Xach einer \veiteren Ausführuntrsiorm kann man die Entfernung ', von sauer wirkenden He.standtcilen, wie z. B. '■ Salzsäure, durch Mitverwendung von gas- : >o förmigem Ammoniak begünstigen. Der 1κ·- schriel>ene Reinigungspro/.eK kanu noch da- ; durch begünstigt worden, daß man die ge-' nannten Gase im Gleich- oder liesser Gegeustrom auf die die genannten Temperaturen aufweisenden feindisperseu Stoffe leitet. Die ßehandlungsdauer richtet sich nach den jeweiligen Arlx»itslxidingungeü und wird zunächst so lange gewählt, bis die über den Oxyden l>etindliche Atmosphäre möglichst frei von den zu entfernenden Stoffen, wie z. B. Chlorwasserstoff, geworden ist.It is recommended that the heat treatment in the presence of vapors and gases, such as. B. air, water vapor, nitrogen. (Jeneratorgas and the like to make a Xach \ veiteren Ausführuntrsiorm can ', by acidifying He.standtcilen such as.' By concomitant use of gas removal ■ hydrochloric acid.... Promote> o shaped ammonia The 1κ · - A screeched cleaning process can also be facilitated by the fact that the gases mentioned are directed in constant or counter-current to the finely dispersed substances exhibiting the temperatures mentioned It is initially chosen until the solid atmosphere above the oxides has become as free as possible of the substances to be removed, such as hydrogen chloride.

Die erwähnte Nachbehandlung kann z. B. derart erfolgen, daß die in Flammen erzeugten hochdispersen Aerosole auf einem endlosen Stahlband niedergeschlagen und mit dem Stahlband aus der Flammenzone heraus in einem Raum geführt werden, worin die angegebenen Temperaturen von z. B. 300 oder 400° herrschen. Gleichzeitig kann an dieser Stelle ein entsprechend vorerhitzter Strom von Wasserdampf, Luft od. dgl. im Gegenstrom . längs des Stahlbandes geführt werden. Nach Passieren dieser Raumstrecke wird dann das so behandelte Aerosol durch Abstreifer von dem Stahlband gelöst und gesammelt. In vielen Fällen empfiehlt es sich, die Nachl >ehandlung in einer gesonderten Apparatur vorzunehmen. Dabei kann man die in der thermischen Zersetzungskammer erhaltenen hochdispersen Oxyde in mit einer Transportvorrichtung versehene Drehrohre, Thelenpfannen. rotierende Zylinder mit Rieselvorrichtungen od. dgl. einfüllen, welche dann ebenfalls auf die angegebenen Temperaturen erhitzt werden. In diesen Vorrichtungen erfolgt dann die genannte Entfernung bzw. Unschädlichmachung von unerwünschten Beimengungen, ebenfalls mit Vorteil unter Mitverwendung von strömenden Gasen oder Dämpfen. Wie überraschenderweise festgestellt wurde, findet \>ei dieser Nachbehandlung keine Verschlechterung des Dispersitätsgrades der Aerosole statt. Die Produkte fallen in reiner Form an und können infolgedessen den verschiedensten Verwendungsmöglichkeiten zugeführt werden.The mentioned aftertreatment can, for. B. be carried out in such a way that the highly dispersed aerosols generated in flames are deposited on an endless steel belt and guided with the steel belt out of the flame zone in a room in which the specified temperatures of z. B. 300 or 400 ° prevail. At the same time, a correspondingly preheated stream of steam, air or the like can be used in countercurrent at this point. be guided along the steel belt. After passing this space, the aerosol treated in this way is then removed from the steel belt by wipers and collected. In many cases it is advisable to carry out the post-treatment in a separate apparatus. The highly disperse oxides obtained in the thermal decomposition chamber can be transferred to rotary tubes, Thelen pans, which are provided with a transport device. Fill rotating cylinders with trickle devices or the like, which are then also heated to the specified temperatures. In these devices, the above-mentioned removal or rendering harmless of undesired admixtures then takes place, likewise advantageously with the use of flowing gases or vapors. As surprisingly found \> ei is this aftertreatment no deterioration of dispersion of aerosols instead. The products are obtained in pure form and can therefore be used in a wide variety of ways.

Claims (2)

PATENTANSPROGHE:PATENT PROGRAM: i. Verfahren zum Reinigen von hochdispersen Oxyden von Metallen bzw. Metalloiden, die durch thermische Zersetzung von Verbindungen dieser Metalle bzw. Metalloide in dampfförmigem Zustand in Gegenwart oxydierend bzw. hydrolysierend wirkender (läse oder Dämpfe erhalten werden, dadurch gekennzeichnet, daß die abgeschiedenen Oxyde einer Wärmel>ehandlung 1km Temperaturen von etwa 200 bis etwa 500" gegebenenfalls in iao strömenden gas- oder dampfförmigen Medien so lange unterworfen werden, bis diei. Process for cleaning highly dispersed oxides from metals or Metalloids, which are produced by thermal decomposition of compounds of these metals or metalloids in a vaporous state in the presence of oxidizing or hydrolyzing effects (lase or vapors are obtained , characterized in that the deposited oxides are subjected to a heat treatment at 1km temperatures of about 200 to about 500 ", possibly in general flowing gaseous or vaporous media are subjected to until the von der Zersetzung stammenden Verunreinigungen ganz oder weitgehend entfernt sind.all or most of the impurities originating from the decomposition are removed are. 2. Verfahren zum Reinigen, hochdisperser Oxyde nach Anspruch i, dadurch gekennzeichnet, daß die Erhitzung der Oxyde noch im Herstellungsverfahren unmittelbar nach der Abscheidung auf den Niederschlagsflächen erfolgt.2. A method for cleaning highly disperse oxides according to claim i, characterized characterized in that the heating of the oxides is still in the manufacturing process immediately after the deposition the precipitation areas. Zur Abgrenzung des Erfindungsgegenstands io vom Stand der Technik sind im Erteilungsverfahren folgende Druckschriften in Betracht gezogen worden:To differentiate the subject matter of the invention from the state of the art, the granting procedure the following publications have been considered: Deutsche Patentschrift Xr. 638 055: USA.-Patentschrift Nr. 1850286;German patent specification Xr. 638 055: U.S. Patent No. 1850286; Barth, Die Metallverrlüchtigungsverfaliren, 1935, S. 183, Abs. 1 und 2 v. u., S. 191, Abs. 3.Barth, The Metal Evaporation Verfaliren, 1935, p. 183, paras. 1 and 2 v. u., P. 191, para. 3. 0 5319 7.520 5319 7.52
DED87110D 1942-02-28 1942-02-28 Process for cleaning finely divided oxides from metals or metalloids Expired DE762723C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DED87110D DE762723C (en) 1942-02-28 1942-02-28 Process for cleaning finely divided oxides from metals or metalloids

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Application Number Priority Date Filing Date Title
DED87110D DE762723C (en) 1942-02-28 1942-02-28 Process for cleaning finely divided oxides from metals or metalloids
DE1007493X 1948-12-31

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1097960B (en) * 1954-07-20 1961-01-26 Socony Mobil Oil Co Inc Process for increasing the mean pore diameter of dry porous inorganic oxide hydrate masses or their calcination products
DE1150955B (en) * 1961-04-20 1963-07-04 Degussa Method and device for cleaning highly dispersed oxides
DE102013112520A1 (en) 2012-12-12 2014-06-12 Dirk Ledermüller Process for producing a monolithic heat-insulating molded body and heat-insulating molded body
WO2015109068A1 (en) 2014-01-16 2015-07-23 W. R. Grace & Co.-Conn. Affinity chromatography media and chromatography devices
US11628381B2 (en) 2012-09-17 2023-04-18 W.R. Grace & Co. Conn. Chromatography media and devices

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1097960B (en) * 1954-07-20 1961-01-26 Socony Mobil Oil Co Inc Process for increasing the mean pore diameter of dry porous inorganic oxide hydrate masses or their calcination products
DE1150955B (en) * 1961-04-20 1963-07-04 Degussa Method and device for cleaning highly dispersed oxides
US11628381B2 (en) 2012-09-17 2023-04-18 W.R. Grace & Co. Conn. Chromatography media and devices
DE102013112520A1 (en) 2012-12-12 2014-06-12 Dirk Ledermüller Process for producing a monolithic heat-insulating molded body and heat-insulating molded body
EP2743243A2 (en) 2012-12-12 2014-06-18 Dirk Ledermüller Method for producing a monolithic moulded body made from heat insulating material and moulded body made from heat insulating material
WO2015109068A1 (en) 2014-01-16 2015-07-23 W. R. Grace & Co.-Conn. Affinity chromatography media and chromatography devices

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