EP4055198A1 - Method for obtaining platinum and/or ruthenium - Google Patents

Method for obtaining platinum and/or ruthenium

Info

Publication number
EP4055198A1
EP4055198A1 EP20780670.4A EP20780670A EP4055198A1 EP 4055198 A1 EP4055198 A1 EP 4055198A1 EP 20780670 A EP20780670 A EP 20780670A EP 4055198 A1 EP4055198 A1 EP 4055198A1
Authority
EP
European Patent Office
Prior art keywords
solution
platinum
ruthenium
ozone
concentration
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.)
Pending
Application number
EP20780670.4A
Other languages
German (de)
French (fr)
Inventor
Alexander Eifert
Claudio Baldizzone
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP4055198A1 publication Critical patent/EP4055198A1/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B11/00—Obtaining noble metals
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B11/00—Obtaining noble metals
    • C22B11/04—Obtaining noble metals by wet processes
    • C22B11/042—Recovery of noble metals from waste materials
    • C22B11/046—Recovery of noble metals from waste materials from manufactured products, e.g. from printed circuit boards, from photographic films, paper or baths
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B11/00—Obtaining noble metals
    • C22B11/04—Obtaining noble metals by wet processes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B11/00—Obtaining noble metals
    • C22B11/06—Chloridising
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
    • C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
    • C22B3/10—Hydrochloric acid, other halogenated acids or salts thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/54—Reclaiming serviceable parts of waste accumulators
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Definitions

  • the present invention relates to a process for the production of platinum and / or ruthenium. This is particularly suitable for recovering platinum from fuel cells.
  • Platinum is an essential raw material that is used, among other things, in membrane electrode assemblies (MEA). These represent a core component of fuel cells. They consist of a central polymer membrane, two catalyst layers on each side in which the platinum is arranged, and two carbon layers on each side. A fuel cell stack contains more than 100 such MEAs. A fuel cell stack consists of more than 80% by weight of carbon, but still contains around 30 g of precious metals. The recovery of platinum and other precious metals can be done pyrometallurgical or hydrometallurgical.
  • MEA membrane electrode assemblies
  • the method for obtaining platinum and / or ruthenium in particular platinum, provision is made for a solution of an alcohol in water to be provided. At least one starting material is introduced into this solution which contains platinum and / or ruthenium and is to be obtained from the platinum and / or ruthenium.
  • this starting material is an MEA or its fragments.
  • the alcohol is suitable for dissolving ionomeric binders within a few minutes, which bind a platinum-based and / or ruthenium-based catalyst, the carbon layers and the membrane to one another. In this way, a suspension can be obtained in which the catalyst is separate from the other constituents of the MEA.
  • HCl is introduced into the solution. This can be done in particular by adding hydrochloric acid. In this way the pH of the solution is lowered, which stabilizes hexachloroplatinate (IV) complexes and hexachloro ruthenate (lII) complexes.
  • Baldizzone in the above-mentioned article it is now necessary to add a reducing agent to the solution in order to reduce the platinum oxide layer and / or ruthenium oxide layer again .
  • the alcohol plays a dual role in the proceedings. It not only functions as a solvent to dissolve ionomeric binders, but also functions as a reducing agent in hydrochloric acid solution and in the absence of ozone compared to platinum oxide and / or ruthenium oxide.
  • the alcohol is preferably selected from the group consisting of methanol, ethanol and isopropanol. Ethanol is particularly preferred.
  • the concentration of the alcohol in the solution provided is preferably above 50% by weight. This enables ionic binders to dissolve quickly. For the purpose of reducing platinum oxide and / or ruthenium oxide, however, a concentration in the range from 10% by weight to 20% by weight is sufficient. In order to reduce the process costs, it is therefore preferred that after the introduction of the at least one starting material and before the first introduction of ozone, the concentration of the alcohol in the solution is lowered to a value in this range. This can be done in particular by diluting the solution with water.
  • the concentration of HCl in the solution is preferably adjusted to a value in the range from 0.05 mol / l to 0.50 mol / l when introducing HCl. This gives a pH value which is optimal for the oxidation of platinum and / or ruthenium with ozone.
  • sodium chloride is introduced into the solution in a concentration of 0.5 mol / l to 5.0 mol / l. This increases the concentration of chloride ions in the solution in order to be able to stabilize large amounts of platinum in the form of hexachloroplatinate (IV) complexes and / or of ruthenium in the form of hexachlororuthenate (III) complexes in the solution.
  • the ozone is preferably passed into the solution as an ozone / oxygen mixture. Such a mixture can be produced in a simple manner by means of an ozonizer.
  • the ozone concentration in the solution is preferably not adjusted to more than 5% by weight. Higher ozone concentrations no longer contribute significantly to the oxidation of platinum and / or ruthenium, but mainly cause the alcohol to be oxidized.
  • Each initiation is preferably carried out over a period of time in the range from 30 seconds to 30 minutes. Such a period of time is sufficient in the case of a catalyst material as it is usually used in an MEA to cover the entire platinum surface with a platinum oxide layer and / or the entire ruthenium surface with a ruthenium oxide layer. A further introduction of ozone will therefore not cause any oxidation of platinum and / or ruthenium, but only an oxidation of the alcohol.
  • the solution is flushed with an inert gas such as, in particular, nitrogen or argon.
  • an inert gas such as, in particular, nitrogen or argon.
  • the platinum and / or ruthenium can be obtained reductively from the solution.
  • the remaining solid material can be filtered off from the solution and then, for example, with hydrogen or treated with another reducing agent in order to precipitate metallic platinum and / or ruthenium from the solution.
  • FIG. 1 shows a flow chart of an exemplary embodiment of the method according to the invention.
  • FIG. 2 shows schematically the transient dissolution of platinum in an exemplary embodiment of the method according to the invention.
  • a solution of ethanol in water is first provided 11.
  • this contains 90% by weight of ethanol and 10% by weight of water.
  • This is followed by introduction 12 of starting materials 20 in the form of a comminuted MEA into the solution.
  • the solution is stirred for 10 minutes, during which the ionomeric binders of the MEA go into solution and the MEA parts thereby disintegrate into the catalyst, the carbon and the membrane.
  • the solution is then diluted 13 with water until its ethanol content has fallen to 20% by weight.
  • Sufficient hydrochloric acid is then added 14 that the HCl concentration in the solution is 0.1 mol / l and its pH value falls to 1 as a result.
  • Sodium chloride is also added 15 so that the solution contains 1 mol / l sodium chloride. The transient dissolution of the platinum from the starting material 20 is then started.
  • a mixture of oxygen and ozone generated by means of the corona effect is introduced 16 over a period of 10 minutes, care being taken that the ozone concentration in the solution does not rise above 5% by weight.
  • the solution is then flushed 17 with nitrogen. After a further 10 minutes, the introduction 16 of ozone is repeated.
  • FIG. 2 when metallic platinum 21 is treated with ozone, platinum cations go into solution, which are immediately stabilized as hexachloroplatinate (IV) complexes.
  • a platinum oxide layer 22 gradually forms on the surface of the platinum 21 until the surface is completely covered and the dissolution of platinum 21 ends.
  • the ethanol begins to reduce the platinum oxide layer 22, with platinum cations again going into solution.
  • This reduction step ends when the entire platinum surface has been freed from platinum oxide 22.
  • the next oxidation step then begins with the renewed introduction 16 of ozone into the solution. These steps are repeated until a test 18 shows that the platinum 21 has been completely dissolved.
  • the test 18 checks whether a predetermined number of oxidation and reduction cycles have been run through, after which the complete dissolution of the platinum 21 is expected.
  • the process is then terminated 19 in that the residues of the starting materials 20 are filtered off from the solution and this is passed on to a re ductive work-up. There, metallic platinum can be precipitated reductively by introducing hydrogen into the solution.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Inert Electrodes (AREA)

Abstract

The present invention relates to a method for obtaining platinum and/or ruthenium. Said method comprises the provision of a solution of ethanol in water (11), the introduction of at least one starting material (20) into the solution (12), the introduction of HCl into the solution (14) and a multiple introduction of ozone into the solution (16).

Description

Beschreibung description
Titel title
Verfahren zur Gewinnung von Platin und/oder Ruthenium Process for the extraction of platinum and / or ruthenium
Die vorliegende Erfindung betrifft ein Verfahren zur Gewinnung von Platin und/o der Ruthenium. Dieses ist insbesondere dazu geeignet, Platin aus Brennstoffzel len zurückzugewinnen. The present invention relates to a process for the production of platinum and / or ruthenium. This is particularly suitable for recovering platinum from fuel cells.
Stand der Technik State of the art
Platin ist ein essentieller Rohstoff, der unter anderem in Membranelektrodenein heiten (membrane electrode assembly; MEA) Verwendung findet. Diese stellen einen Kernbestandteil von Brennstoffzellen dar. Sie bestehen aus einer zentralen Polymermembran, zwei Katalysatorschichten pro Seite, in denen das Platin an geordnet ist, und zwei Kohlenstoffschichten pro Seite. Ein Brennstoffzellenstapel enthält mehr als 100 solcher MEAs. Ein Brennstoffzellenstapel besteht zu mehr als 80 Gew.-% aus Kohlenstoff, enthält aber dennoch circa 30 g Edelmetalle. Die Rückgewinnung von Platin und anderen Edelmetallen kann pyrometallurgisch o- der hydrometallurgisch erfolgen. Platinum is an essential raw material that is used, among other things, in membrane electrode assemblies (MEA). These represent a core component of fuel cells. They consist of a central polymer membrane, two catalyst layers on each side in which the platinum is arranged, and two carbon layers on each side. A fuel cell stack contains more than 100 such MEAs. A fuel cell stack consists of more than 80% by weight of carbon, but still contains around 30 g of precious metals. The recovery of platinum and other precious metals can be done pyrometallurgical or hydrometallurgical.
Bei der hydrometallurgischen Rückgewinnung werden die zurück zu gewinnen den Metalle durch Komplexbildung in eine wässrige Lösung gebracht. Ein Bei spiel für ein solches Verfahren wird in dem Artikel N. Hodnik, C. Baldizzone, „Pla- tinum recycling going green via induced surface potential alteration enabling fast and efficient dissolution“ schließen, 2016, Nature Communications, Volume 7, beschrieben. Dabei kann aus einem Industriekatalysator Platin mit Chlorid als Komplexbildner in salzsaurer Lösung erfolgen. Dabei wird abwechselnd Ozon als Oxidationsmittel und Kohlenmonoxid als Reduktionsmittel eingesetzt, um so eine transiente Auflösung des Platins zu erreichen. Offenbarung der Erfindung In hydrometallurgical recovery, the metals to be recovered are brought into an aqueous solution through complex formation. An example of such a process is described in the article N. Hodnik, C. Baldizzone, “Platinum recycling going green via induced surface potential alteration enabling fast and efficient dissolution”, 2016, Nature Communications, Volume 7. An industrial catalyst can be used to produce platinum with chloride as a complexing agent in a hydrochloric acid solution. Ozone is used alternately as the oxidizing agent and carbon monoxide as the reducing agent in order to achieve a transient dissolution of the platinum. Disclosure of the invention
In dem Verfahren zur Gewinnung von Platin und/oder Ruthenium, insbesondere von Platin, ist vorgesehen, dass eine Lösung eines Alkohols in Wasser bereitge stellt wird. In diese Lösung wird mindestens ein Ausgangsmaterial eingebracht, welches Platin und/oder Ruthenium enthält und aus dem Platin und/oder Ruthe nium gewonnen werden soll. Insbesondere handelt es sich bei diesem Aus gangsmaterial um ein MEA oder dessen Bruchstücke. Der Alkohol ist geeignet um innerhalb weniger Minuten ionomere Bindemittel aufzulösen, welche einen platinbasierten und/oder rutheniumbasierten Katalysator, die Kohlenstoffschich ten und die Membran miteinander verbinden. Auf diese Weise kann eine Suspen sion erhalten werden, in welcher der Katalysator getrennt von den anderen Be standteilen des MEAs vorliegt. In the method for obtaining platinum and / or ruthenium, in particular platinum, provision is made for a solution of an alcohol in water to be provided. At least one starting material is introduced into this solution which contains platinum and / or ruthenium and is to be obtained from the platinum and / or ruthenium. In particular, this starting material is an MEA or its fragments. The alcohol is suitable for dissolving ionomeric binders within a few minutes, which bind a platinum-based and / or ruthenium-based catalyst, the carbon layers and the membrane to one another. In this way, a suspension can be obtained in which the catalyst is separate from the other constituents of the MEA.
Anschließend wird HCl in die Lösung eingebracht. Dies kann insbesondere durch Hinzufügen von Salzsäure erfolgen. Auf diese Weise wird der pH-Wert der Lö sung abgesenkt, was Hexachloroplatinat(IV)- Komplexe und Hexachloro- ruthenat(l II)- Komplexe stabilisiert. Then HCl is introduced into the solution. This can be done in particular by adding hydrochloric acid. In this way the pH of the solution is lowered, which stabilizes hexachloroplatinate (IV) complexes and hexachloro ruthenate (lII) complexes.
Schließlich werden mehrere Oxidationsschritte durchgeführt, indem Ozon in die Lösung eingeleitet wird. Dieses kann das im Katalysator enthaltende Platin und/oder Ruthenium in saurer Lösung oberflächlich oxidieren. Dabei erfolgt eine transiente Auflösung von Platin und/oder Ruthenium unter Bildung eines lösli chen Hexachloroplatinat(IV)- Komplexes und/oder Hexachlororuthenat(lll)- Komplexes. Sobald der Katalysator vollständig von einer Platinoxidschicht und/o der Rutheniumoxidschicht bedeckt ist, geht kein weiteres Platin und/oder Ruthe nium in Lösung. Im herkömmlichen transienten Auflösungsverfahren für Edelme talle wie sie beispielsweise von N. Hodnick und C. Baldizzone in dem oben er wähnten Artikel beschrieben werden, ist es nun erforderlich, der Lösung ein Re duktionsmittel hinzuzufügen, um die Platinoxidschicht und/oder Rutheniumoxid schicht wieder zu reduzieren. Dies ist im vorliegenden Verfahren nicht erforder lich. Der Alkohol erfüllt in dem Verfahren nämlich eine Doppelrolle. Es fungiert nicht nur als Lösungsmittel um ionomere Bindemittel aufzulösen, sondern es fun giert außerdem in salzsaurer Lösung und in Abwesenheit von Ozon gegenüber Platinoxid und/oder Rutheniumoxid als Reduktionsmittel. Nachdem die Einleitung von Ozon beendet wurde, erfolgt also eine Reduktion des Platinoxids und/oder Rutheniumoxids an der Katalysatoroberfläche und weiteres Platin und/oder Ru thenium geht transient als Hexachloroplatinat(IV) und/oder Hexachloro- ruthenat(lll) in Lösung bis die Platinoberfläche und/oder Rutheniumoberfläche wieder frei von Platinoxid und/oder Rutheniumoxid ist. Zu diesem Zeitpunkt endet erneut die Auflösung von Platin und/oder Ruthenium und ein neuerliches Einlei ten von Ozon in die Lösung ist erforderlich, um weiteres Platin und/oder Ruthe nium in Lösung zu bringen. Finally, several oxidation steps are carried out by introducing ozone into the solution. This can superficially oxidize the platinum and / or ruthenium contained in the catalyst in acidic solution. This results in a transient dissolution of platinum and / or ruthenium with the formation of a soluble hexachloroplatinate (IV) complex and / or hexachlororuthenate (III) complex. As soon as the catalyst is completely covered by a platinum oxide layer and / o the ruthenium oxide layer, no further platinum and / or ruthenium goes into solution. In the conventional transient dissolution process for precious metals as described for example by N. Hodnick and C. Baldizzone in the above-mentioned article, it is now necessary to add a reducing agent to the solution in order to reduce the platinum oxide layer and / or ruthenium oxide layer again . This is not necessary in the present proceedings. The alcohol plays a dual role in the proceedings. It not only functions as a solvent to dissolve ionomeric binders, but also functions as a reducing agent in hydrochloric acid solution and in the absence of ozone compared to platinum oxide and / or ruthenium oxide. After the introduction was terminated by ozone, a reduction of the platinum oxide and / or ruthenium oxide takes place on the catalyst surface and further platinum and / or ruthenium goes transiently as hexachloroplatinate (IV) and / or hexachloro ruthenate (III) in solution until the platinum surface and / or The ruthenium surface is free of platinum oxide and / or ruthenium oxide again. At this point, the dissolution of platinum and / or ruthenium ends again and a renewed introduction of ozone into the solution is necessary in order to bring more platinum and / or ruthenium into solution.
Der Alkohol ist bevorzugt aus der Gruppe ausgewählt, die aus Methanol, Ethanol und Isopropanol besteht. Ethanol ist besonders bevorzugt. Die Konzentration des Alkohols beträgt in der bereitgestellten Lösung vorzugsweise über 50 Gew.-%. Dies ermöglicht ein schnelles Auflösen ionischer Bindemittel. Zum Zweck der Re duktion von Platinoxid und/oder Rutheniumoxid ist hingegen eine Konzentration im Bereich von 10 Gew.-% bis 20 Gew.-% ausreichend. Zur Verringerung der Verfahrenskosten ist es deshalb bevorzugt, dass nach dem Einbringen des min destens einen Ausgangsmaterials und vor dem ersten Einleiten von Ozon, die Konzentration des Alkohols in der Lösung auf einen Wert in diesem Bereich ge senkt wird. Dies kann insbesondere durch Verdünnen der Lösung mit Wasser er folgen. The alcohol is preferably selected from the group consisting of methanol, ethanol and isopropanol. Ethanol is particularly preferred. The concentration of the alcohol in the solution provided is preferably above 50% by weight. This enables ionic binders to dissolve quickly. For the purpose of reducing platinum oxide and / or ruthenium oxide, however, a concentration in the range from 10% by weight to 20% by weight is sufficient. In order to reduce the process costs, it is therefore preferred that after the introduction of the at least one starting material and before the first introduction of ozone, the concentration of the alcohol in the solution is lowered to a value in this range. This can be done in particular by diluting the solution with water.
Die Konzentration von HCl in der Lösung wird beim Einbringen von HCl vorzugs weise auf einen Wert im Bereich von 0,05 mol/l bis 0,50 mol/l eingestellt. Hiermit wird ein pH-Wert erhalten, welcher für die Oxidation von Platin und/oder Ruthe nium mit Ozon optimal ist. The concentration of HCl in the solution is preferably adjusted to a value in the range from 0.05 mol / l to 0.50 mol / l when introducing HCl. This gives a pH value which is optimal for the oxidation of platinum and / or ruthenium with ozone.
Nach dem Einbringen des mindestens einen Ausgangsmaterials und vor dem ersten Einleiten von Ozon, ist es weiterhin bevorzugt, dass Natriumchlorid in ei ner Konzentration von 0,5 mol/l bis 5,0 mol/l in die Lösung eingebracht wird. Hier durch wird die Konzentration von Chloridionen in der Lösung erhöht, um so große Mengen Platin in Form von Hexachloroplatinat(IV)- Komplexen und/oder von Ruthenium in Form von Hexachlororuthenat(lll)-Komplexen in der Lösung stabilisieren zu können. Das Ozon wird vorzugsweise als Ozon/Sauerstoff-Gemisch in die Lösung einge leitet. Ein solches Gemisch kann in einfacher Weise mittels eines Ozonisators hergestellt werden. After introducing the at least one starting material and before introducing ozone for the first time, it is further preferred that sodium chloride is introduced into the solution in a concentration of 0.5 mol / l to 5.0 mol / l. This increases the concentration of chloride ions in the solution in order to be able to stabilize large amounts of platinum in the form of hexachloroplatinate (IV) complexes and / or of ruthenium in the form of hexachlororuthenate (III) complexes in the solution. The ozone is preferably passed into the solution as an ozone / oxygen mixture. Such a mixture can be produced in a simple manner by means of an ozonizer.
Beim Einleiten von Ozon in die Lösung wird die Ozonkonzentration in der Lösung vorzugsweise nicht auf mehr als 5 Gew.-% eingestellt. Höhere Ozonkonzentratio nen tragen nicht mehr wesentlich zur Oxidation von Platin und/oder Ruthenium bei, sondern bewirken hauptsächlich ein Oxidation des Alkohols. When introducing ozone into the solution, the ozone concentration in the solution is preferably not adjusted to more than 5% by weight. Higher ozone concentrations no longer contribute significantly to the oxidation of platinum and / or ruthenium, but mainly cause the alcohol to be oxidized.
Jedes Einleiten erfolgt vorzugsweise über einen Zeitraum, der jeweils im Bereich von 30 Sekunden bis 30 Minuten liegt. Ein solcher Zeitraum reicht bei einem Ka talysatormaterial wie es üblicherweise in einem MEA verwendet wird aus, um die gesamte Platinoberfläche mit einer Platinoxidschicht und/oder die gesamte Ru theniumoberfläche mit einer Rutheniumoxidschicht zu bedecken. Eine weitere Einleitung von Ozon wird deshalb keine Oxidation von Platin und/oder Ruthe nium, sondern nur noch eine Oxidation des Alkohols bewirken. Each initiation is preferably carried out over a period of time in the range from 30 seconds to 30 minutes. Such a period of time is sufficient in the case of a catalyst material as it is usually used in an MEA to cover the entire platinum surface with a platinum oxide layer and / or the entire ruthenium surface with a ruthenium oxide layer. A further introduction of ozone will therefore not cause any oxidation of platinum and / or ruthenium, but only an oxidation of the alcohol.
Zwischen zwei Einleitungen von Ozon in die Lösung ist es jeweils bevorzugt, dass diese mit einem in Inertgas wie insbesondere Stickstoff oder Argon gespült wird. Auf diese Weise wird noch in der Lösung vorhandenes Ozon schnell aus dieser ausgetrieben. Dies ist vorteilhaft, da die Reduktion von Platinoxid und/oder Rutheniumoxid erst einsetzt, wenn die Lösung frei von Ozon ist und bis dahin eine Redoxreaktion zwischen dem Alkohol und dem verbleibenden Ozon abläuft. Between two introductions of ozone into the solution, it is in each case preferred that the solution is flushed with an inert gas such as, in particular, nitrogen or argon. In this way, any ozone still present in the solution is quickly driven out of it. This is advantageous because the reduction of platinum oxide and / or ruthenium oxide does not start until the solution is free of ozone and until then a redox reaction between the alcohol and the remaining ozone takes place.
Das Platin und/oder Ruthenium kann reduktiv aus der Lösung gewonnen werden. Hierzu kann insbesondere nach einer vorgegebenen Anzahl von Einleitungen von Ozon in die Lösung, nach welcher erwartet werden kann, dass kein weiteres Platin und/oder Ruthenium mehr in Lösung geht, das verbleibende Feststoffma terial von der Lösung abfiltriert werden und diese anschließend beispielsweise mit Wasserstoff oder einem anderen Reduktionsmittel behandelt werden, um so metallisches Platin und/oder Ruthenium aus der Lösung auszufällen. The platinum and / or ruthenium can be obtained reductively from the solution. For this purpose, in particular after a predetermined number of introductions of ozone into the solution, after which it can be expected that no further platinum and / or ruthenium will go into solution, the remaining solid material can be filtered off from the solution and then, for example, with hydrogen or treated with another reducing agent in order to precipitate metallic platinum and / or ruthenium from the solution.
Kurze Beschreibung der Zeichnungen Ein Ausführungsbeispiel der Erfindung ist in den Zeichnungen dargestellt und wird in der nachfolgenden Beschreibung näher erläutert. Brief description of the drawings An embodiment of the invention is shown in the drawings and is explained in more detail in the following description.
Figur 1 zeigt ein Ablaufdiagramm eines Ausführungsbeispiels des erfindungsge mäßen Verfahrens. FIG. 1 shows a flow chart of an exemplary embodiment of the method according to the invention.
Figur 2 zeigt schematisch die transiente Auflösung von Platin in einem Ausfüh rungsbeispiel des erfindungsgemäßen Verfahrens. FIG. 2 shows schematically the transient dissolution of platinum in an exemplary embodiment of the method according to the invention.
Ausführungsbeispiel der Erfindung Embodiment of the invention
Wie in Figur 1 dargestellt ist erfolgt nach dem Start 10 eines Ausführungsbei spiels des erfindungsgemäßen Verfahrens zunächst ein Bereitstellen 11 einer Lösung von Ethanol in Wasser. Im vorliegenden Ausführungsbeispiel enthält diese 90 Gew.-% Ethanol und 10 Gew.-% Wasser. Danach erfolgt ein Einbringen 12 von Ausgangsmaterialien 20 in Form eines zerkleinerten MEAs in die Lösung. Die Lösung wird 10 Minuten gerührt, wobei ionomere Bindemittel des MEAs in Lösung gehen und die MEA-Teile dadurch in den Katalysator, den Kohlenstoff und die Membran zerfallen. As shown in FIG. 1, after the start 10 of an exemplary embodiment of the method according to the invention, a solution of ethanol in water is first provided 11. In the present exemplary embodiment, this contains 90% by weight of ethanol and 10% by weight of water. This is followed by introduction 12 of starting materials 20 in the form of a comminuted MEA into the solution. The solution is stirred for 10 minutes, during which the ionomeric binders of the MEA go into solution and the MEA parts thereby disintegrate into the catalyst, the carbon and the membrane.
Es erfolgt nun ein Verdünnen 13 der Lösung mit Wasser bis ihr Ethanolgehalt auf 20 Gew.-% gesunken ist. Anschließend wird soviel Salzsäure zugegeben 14, dass die HCl- Konzentration in der Lösung 0,1 mol/l beträgt und ihr pH-Wert dadurch auf 1 sinkt. Weiterhin erfolgt ein Zugeben 15 von soviel Natriumchlorid, dass die Lösung 1 mol/l Natriumchlorid enthält. Danach wird mit der transienten Auflösung des Platins aus dem Ausgangsmaterial 20 begonnen. The solution is then diluted 13 with water until its ethanol content has fallen to 20% by weight. Sufficient hydrochloric acid is then added 14 that the HCl concentration in the solution is 0.1 mol / l and its pH value falls to 1 as a result. Sodium chloride is also added 15 so that the solution contains 1 mol / l sodium chloride. The transient dissolution of the platinum from the starting material 20 is then started.
Es erfolgt ein Einleiten 16 eines mittels des Korona- Effekts erzeugten Gemischs von Sauerstoff und Ozon über einen Zeitraum von 10 Minuten, wobei darauf ge achtet wird, dass die Ozonkonzentration in der Lösung nicht über 5 Gew.-% steigt. Danach erfolgt ein Spülen 17 der Lösung mit Stickstoff. Nach weiteren 10 Minuten wird das Einleiten 16 von Ozon wiederholt. Wie in Figur 2 dargestellt ist, gehen bei Behandlung von metallischem Platin 21 mit Ozon Platinkationen in Lö sung, die sofort als Hexachloroplatinat(IV)- Komplexe stabilisiert werden. Dabei bildet sich auf der Oberfläche des Platins 21 allmählich eine Platinoxidschicht 22 bis die Oberfläche vollständig bedeckt ist und die Auflösung von Platin 21 endet. Sobald das restliche Ozon aus der Lösung ausgetrieben wurde, beginnt das Ethanol die Platinoxidschicht 22 zu reduzieren, wobei erneut Platinkationen in Lösung gehen. Dieser Reduktionsschritt endet, wenn die die gesamte Platinober- fläche von Platinoxid 22 befreit wurde. Danach beginnt der nächste Oxidations schritt mit dem erneuten Einleiten 16 von Ozon in die Lösung. Diese Schritte wer den solange wiederholt bis eine Prüfung 18 ergibt, dass das Platin 21 vollständig aufgelöst wurde. Im vorliegenden Ausführungsbeispiel wird in der Prüfung 18 ge prüft, ob eine vorgegebene Anzahl von Oxidations- und Reduktionszyklen durch- laufen wurde, nach denen mit der vollständigen Auflösung des Platins 21 gerech net wird. Danach erfolgt ein Beenden 19 des Verfahrens, indem die Reste der Ausgangsmaterialien 20 von der Lösung abfiltriert werden und diese in eine re duktive Aufarbeitung weitergegeben wird. Dort kann durch Einleitung von Was serstoff in die Lösung metallisches Platin reduktiv ausgefällt werden. A mixture of oxygen and ozone generated by means of the corona effect is introduced 16 over a period of 10 minutes, care being taken that the ozone concentration in the solution does not rise above 5% by weight. The solution is then flushed 17 with nitrogen. After a further 10 minutes, the introduction 16 of ozone is repeated. As shown in FIG. 2, when metallic platinum 21 is treated with ozone, platinum cations go into solution, which are immediately stabilized as hexachloroplatinate (IV) complexes. A platinum oxide layer 22 gradually forms on the surface of the platinum 21 until the surface is completely covered and the dissolution of platinum 21 ends. As soon as the remaining ozone has been driven out of the solution, the ethanol begins to reduce the platinum oxide layer 22, with platinum cations again going into solution. This reduction step ends when the entire platinum surface has been freed from platinum oxide 22. The next oxidation step then begins with the renewed introduction 16 of ozone into the solution. These steps are repeated until a test 18 shows that the platinum 21 has been completely dissolved. In the present exemplary embodiment, the test 18 checks whether a predetermined number of oxidation and reduction cycles have been run through, after which the complete dissolution of the platinum 21 is expected. The process is then terminated 19 in that the residues of the starting materials 20 are filtered off from the solution and this is passed on to a re ductive work-up. There, metallic platinum can be precipitated reductively by introducing hydrogen into the solution.

Claims

Ansprüche Expectations
1. Verfahren zur Gewinnung von Platin und/oder Ruthenium, umfassend die fol genden Schritte: a) Bereitstellen einer Lösung eines Alkohols in Wasser (11), b) Einbringen mindestens eines Ausgangsmaterials (20) in die Lösung (12), welches Platin und/oder Ruthenium enthält, c) Einbringen von HCl in die Lösung (14), d) Mehrfaches Einleiten von Ozon in die Lösung (16). 1. A method for the production of platinum and / or ruthenium, comprising the fol lowing steps: a) providing a solution of an alcohol in water (11), b) introducing at least one starting material (20) into the solution (12), which platinum and / or contains ruthenium, c) introduction of HCl into the solution (14), d) multiple introduction of ozone into the solution (16).
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Konzentration des Alkohols in Schritt a) über 50 Gew.-% beträgt und zwischen Schritt b) und Schritt d) auf eine Konzentration im Bereich von 10 Gew.-% bis 20 Gew.- % gesenkt wird (13). 2. The method according to claim 1, characterized in that the concentration of the alcohol in step a) is over 50 wt .-% and between step b) and step d) to a concentration in the range of 10 wt .-% to 20 wt. -% is reduced (13).
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die Kon zentration von HCl in der Lösung in Schritt c) auf einen Wert im Bereich von 0,05 mol/l bis 0,50 mol/l eingestellt wird. 3. The method according to claim 1 or 2, characterized in that the concentration of HCl in the solution in step c) is set to a value in the range from 0.05 mol / l to 0.50 mol / l.
4. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass zwischen Schritt b) und Schritt d) NaCI in einer Konzentration von 0,5 mol/l bis 5,0 mol/l in die Lösung eingebracht wird (15). 4. The method according to any one of claims 1 to 3, characterized in that between step b) and step d) NaCl is introduced into the solution in a concentration of 0.5 mol / l to 5.0 mol / l (15).
5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Ozon als Ozon/Sauerstoff-Gemisch in die Lösung eingeleitet wird. 5. The method according to any one of claims 1 to 4, characterized in that the ozone is introduced into the solution as an ozone / oxygen mixture.
6. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die Konzentration von Ozon in der Lösung in Schritt d) maximal 10 Gew.-% beträgt. 6. The method according to any one of claims 1 to 5, characterized in that the concentration of ozone in the solution in step d) is a maximum of 10 wt .-%.
7. Verfahren nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass jedes Einleiten (16) über einen Zeitraum erfolgt, der jeweils im Bereich von 30 Sekunden bis 30 Minuten liegt. 7. The method according to any one of claims 1 to 6, characterized in that each introduction (16) takes place over a period of time which is in the range of 30 seconds to 30 minutes.
8. Verfahren nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass die Lösung zwischen zwei Einleitungen (16) von Ozon jeweils mit mindestens einem Inertgas gespült wird (17). 8. The method according to any one of claims 1 to 7, characterized in that the solution between two inlets (16) of ozone is each flushed with at least one inert gas (17).
9. Verfahren nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass das Platin und/oder Ruthenium reduktiv aus der Lösung gewonnen wird. 9. The method according to any one of claims 1 to 8, characterized in that the platinum and / or ruthenium is obtained reductively from the solution.
EP20780670.4A 2019-11-07 2020-09-24 Method for obtaining platinum and/or ruthenium Pending EP4055198A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102019217188.5A DE102019217188A1 (en) 2019-11-07 2019-11-07 Process for the extraction of platinum and / or ruthenium
PCT/EP2020/076755 WO2021089233A1 (en) 2019-11-07 2020-09-24 Method for obtaining platinum and/or ruthenium

Publications (1)

Publication Number Publication Date
EP4055198A1 true EP4055198A1 (en) 2022-09-14

Family

ID=72659238

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20780670.4A Pending EP4055198A1 (en) 2019-11-07 2020-09-24 Method for obtaining platinum and/or ruthenium

Country Status (4)

Country Link
EP (1) EP4055198A1 (en)
CN (1) CN114599805A (en)
DE (1) DE102019217188A1 (en)
WO (1) WO2021089233A1 (en)

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3935798A1 (en) * 1989-10-27 1991-05-02 Basf Ag METHOD FOR OBTAINING RUTHENIUM TETROXIDE BY OXIDATION OF AQUEOUS SOLUTIONS OF ALKALI RUTHENATES
DE10000274C1 (en) * 2000-01-05 2001-05-03 Heraeus Gmbh W C Process for recovering osmium and ruthenium from precious metal concentrates comprises collecting osmium tetroxide in an absorption solution and leaching out ruthenium with an agent
DE102005061954A1 (en) * 2005-12-23 2007-07-05 Basf Ag Recycling of ruthenium from an used ruthenium catalyst comprises treating the catalyst containing ruthenium oxide in a hydrogen stream and treating the carrier material containing ruthenium metal with hydrochloric acid
CN102405298B (en) * 2008-12-30 2014-08-27 巴斯夫欧洲公司 Method for recovering ruthenium from spent catalysts containing ruthenium oxide
JP5513854B2 (en) * 2009-11-11 2014-06-04 エコシステムリサイクリング株式会社 Separation method of platinum and ruthenium
MY160898A (en) * 2010-09-03 2017-03-31 Jx Nippon Mining & Metals Corp Recovery method for high purity platinum
US9580826B2 (en) * 2013-04-11 2017-02-28 Syddansk Universitet Method for recovering platinum group metals from catalytic structures
DE102015118279A1 (en) * 2015-10-27 2017-04-27 Max-Planck-Institut Für Eisenforschung GmbH Process for recovering precious metals

Also Published As

Publication number Publication date
DE102019217188A1 (en) 2021-05-12
WO2021089233A1 (en) 2021-05-14
CN114599805A (en) 2022-06-07

Similar Documents

Publication Publication Date Title
DE60304517T2 (en) Anode for polymer electrolyte fuel cells
DE60208262T2 (en) Process for producing an anode catalyst for fuel cells
DE112010005263B4 (en) Platinum monolayer on hollow, porous nanoparticles with large surface areas and fabrication process
DE10258177A1 (en) Membrane-electrode arrangement used for polymer electrolyte fuel cells comprises a cathode, an anode and a polymer electrolyte membrane arranged between the electrodes
DE10392375T5 (en) Separation process for platinum group elements
DE102012222099A1 (en) Method for restoring the performance of a fuel cell
DE102014110578A1 (en) FUEL CELL ELECTRODE CATALYST, METHOD FOR THE PRODUCTION THEREOF, FUEL CELL CATALYST LOADING ELECTRODE AND FUEL CELL
DE112022000718T5 (en) METHOD FOR RECOVERING NICKEL FROM IRON-ALUMINUM SLAG OBTAINED BY BATTERY POWDER leaching
DE2302150A1 (en) PROCESS FOR SEPARATION AND PURIFICATION OF PLATINUM METALS AND GOLD
DE102019129071A1 (en) Electrolyser and method for splitting water
EP4055198A1 (en) Method for obtaining platinum and/or ruthenium
DE1542105C3 (en) Catalysts for fuel elements and processes for their production
EP3957759A1 (en) Method for the recovery of platinum and / or ruthenium
WO2019219444A1 (en) Method for recovering gold, silver and platinum metals from components of a fuel cell stack or of an electrolyzer
DE2549621A1 (en) AIR ELECTRODE FOR ELECTROCHEMICAL CELLS
DE10007652A1 (en) Methanol fuel cell comprises anion conducting membrane arranged between anode chamber and cathode chamber, and means for feeding water from anode chamber to cathode chamber
WO2015193515A1 (en) Method for processing noble metal-containing materials
DE102018002337A1 (en) A method for reducing halogen ion contamination in solid polymer electrolyte fuel cell
WO2019137714A1 (en) Method for obtaining gold, silver and platinum group metals
EP1873116A1 (en) Graphite processing method and a reactor for carrying out said method
DE2263636A1 (en) FUEL ELEMENT
DE1546728B2 (en) Process for the production of a powdery catalyst for oxygen electrodes containing silver
DE102007056352A1 (en) Process for the preparation of electrode catalyst material mixtures for fuel cells
DE102016008597A1 (en) Proton-conducting composite electrolyte with improved additives for fuel cells
DE102011120328A1 (en) Etching process for metal mixed oxides

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

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

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

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

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

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20220607

AK Designated contracting states

Kind code of ref document: A1

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

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)