LU86730A1 - METHOD FOR OBTAINING HEAVY METAL IONS FROM PYRITES AND LIGAND MATERIAL - Google Patents

Description

«-> L-3149

'' 't - "Si 1 GRAND-DUCHÉ DE LUXEMBOURG

} \., Λ '. r * ^

Rrevet N ° '* ..... *

Monsieur le Ministre | -, «t .4 Q» ’i J», you ....... 9 ....... 3 anvler ....... J - '®'. de l'Economie et des Classes Moyennes

fcT ^ V UÄJ

_, "Lx-Liæ: Service de la Propriété Intellectuelle

Titre delivre .............................................

L_I_______J LUXEMBOURG

Demande de Brevet d'invention ° i- _____________________________________________...: .................................___ .. ......_____________________________________________________________________..._______________ (î) I. Requête

Axel Schlosser, Schillerstrasse 7, D-4000 Düsseldorf, __________ (2) représenté par Monsieur Jean Waxweiler, 55 rue des Bruyères, Howald, agissant en qualité de mandataire dépose (nt) ce six janvier mil neuf cent soixante-sept _________________________ ______ ___ ( 4) à ______heures, au Ministère de l'Économie et des Classes Moyennes, à Luxembourg: 1. la présente requête pour l'obtention d'un brevet d'invention concernant:

Procedure for. Extraction. .of "heavy metal ions from. pyrites .. (5) and ligand material________________________ ______________________ _____ 2. la description en langue allemande____________________ _______________________de l'invention en trois exemplaires: 3. ....... / ......... ...................... planches de dessin, en trois exemplaires: 4th la quittance des taxes versées au Bureau de l'Enregistrement à Luxembourg, le JÎILeP-Lr 1987 _.............................; 5. la délégation de pouvoir, datée de ......................................... .................................................. ....... le .......................................... ...............................: 6. le document d'ayant cause (authorization); déclare (nt) en assumant la responsabilité de cette déclaration, que l ’(es) inventeur (s) est (sont): (6)

Axel ...... Schlosser, ....... Schillerstrasse 7, D-4000 Düsseldorf ______________________________________ revendique (nt) pour la susdite demande de brevet la priorité d'une (des) demande (s) de (7) .................................................. ...... / ........................................... .................................................. ............ déposée (s) en (8) .......... / ................... .................................................. .................................................. ..........

le (9) ............................ / ................. .................................................. .................................................. .................................................. .................................................. .................................................. ...............................-.......

sous le N ° (10) ........... / ............................... ................................................!. .................................................. ...........................-.........-............ ..................................... ............. ................................

au nom de (11) ......... ί .................................. .................................................. .................................................. ........ .......................................... .................................................. .................................................. ..........

élit (élisent) domicile pour lui (elle) et, si désigné, pour son mandataire, à Luxembourg ............................. .................................................. ....

....... 55 ...... rue ...... de s ...... Bruyères., ....... Howald _________________________________________________________________________________________-......... ............................................ (12) sollicite (nt ) la délivrance d'un brevet d'invention pour l'objet décrit et représenté dans les annexes susmentionnées, avec ajournement de cette délivrance à ...................... .............- fX ...........-........ — ........ — ..... ..................-_____________________________________________________________ mois. (13)

Le «KjSSBBfe / mandataire: ............................................ .................................................. ....................................... (14) Π. Procès-verbal de Dépôt

La susdite demande de brevet d’invention a été déposée au Ministère de l’Économie et des Classes Moyennes,

Service de la Propriété Intellectuelle à’Luxembourg, en date du: 06.01.1987 /> · '"Ά N, V.

I £ /; i- \ -, Pr. Le Ministre de l'Economi; et des Classes Moyennes, à 15.00 ...... heures î Sj, · ·: p. i.

\ 4 \ / Le chef du service de la> ropriété intellectuelle, cP? % i / · 'sy /' EXPI IL Alh rS RF.LAÏÏVES Al FORMU-AîReDE DEP07 J / \ »si) yi lisü''L> -wn.di) dt dt vcrtjfics: d addùion au brevet principal, a la demcudc dé brevet prinapal Ne ........... you. Jjf ... \ ** - (25inscrire les nom.prénom.profession.

ί χ- ') L-3149 *

DESCRIPTION OF A PATENT APPLICATION IN

GRAND DUCHY OF LUXEMBOURG

Axel Schlosser_

Schillerstrasse 7 D-4000 Dusseldorf

Process for the extraction of heavy metal ions from pyrites and ligand material - 1 -

The invention relates to a process for the economic extraction of heavy metals. Sehwer metal ions from ligand material. In particular, the invention relates to a method for obtaining 5 heavy metal ions or heavy metals from iron oxide lithium.

Ligands are higher-order compounds in which the central atom, more correctly the central ion, is at the center of a crystal lattice. The central ion is often a heavy metal ion with a small radius, e.g. Fe, Cr, Co, Ni, Pt, Cu, Ag, Au, Pd, Rh, Ir, Ru etc. Even non-metals can take on the role of the central atom.

Around this central atom, further atoms, ions, radicals or moles-15 küj.e are grouped in a regular, spatial arrangement, which are known as ligands. In many cases, the central atoms form stable bonds with the ligands, so that they remain together when the higher-order compound is dissolved and do not or only slightly disintegrate into ions or other fragments. Such stable central atom ligand groups are also referred to as

Complexes. These complexes are very stable and their chemical properties are so fundamentally different from the individual ions, radicals or molecules present that the individual constituents and in particular the heavy metals such as e.g. Platinum, gold, palladium, etc. can no longer be detected using conventional analysis methods. The complex can be an anion, a cation or a neutral molecule. (Prof. Dr.

Herrman ROEMPP, chemical lexicon 6th assembly, volume 2) ..

Known ligands containing heavy metals are, for example. spe-50 specific iron oxides, blast furnace slag, fly ash, lava.

The heavy metals in these ligands can be present as so-called triads in the form of spherical packings. Triad No. 1 includes ruthenium, rhodium and palladium, triad no. 2 includes osmium, iridium and platinum where Triad No. 3 is composed of 35 gold, silver and copper. These triads are exclusively ionic elements with a 7 - 2 - y unfilled outer electron shell. X see Werner's coordination theory).

Although it was known that these ligand materials contain relatively high noble metal contents, in particular platinides, the extraction of the heavy metals contained has hitherto been difficult to carry out economically. Pyrite burns, Ligandmagne-tite and the like Materials are often deposited as overburden or used as fillers in road construction etc.

Blowing furnace processes produce "guildish silver" from pyrites in a precious metal converter, but this process is sometimes very expensive and not economical at all with certain ligand materials.

It was therefore the object of the present invention to describe a method for breaking up the ligand crystal lattice with simultaneous formation of heavy metals, heavy metal salts and heavy metal alloys.

Surprisingly, it was found that ligand materials react violently with a mixture of organic and inorganic acid. After the reaction had subsided, metallic heavy metals, heavy metal salts and heavy metal alloys could be detected in the insoluble residue. It is thus evident that the reaction of an organic and inorganic acid with ligand material breaks the ligand crystal lattice and releases heavy metals.

The reaction mechanism is unknown. It is believed that the reaction of the organic / inorganic acid mixture, which has a theoretical high hydrogen release, with the ligand material first releases hydrogen. It is now known that certain heavy metal ions have the property of absorbing hydrogen in large quantities. For example, Palladium absorb a hundred to a thousand times its volume of hydrogen. The nascent hydrogen, which presumably occurs in the reaction of the inorganic / organic acid ÏTÏT ΤΠ * 1 4 · Λ ^ ΐτη 1 ___: J ja____ -, - 3 - 7

T

the crystal lattice and thus reaches the embedded heavy metal ions. These have an unsaturated noble gas shell which is filled up by the hydrogen. It is believed that the heavy metal ions receive a noble gas configuration and inflate to such an extent that they break the crystal lattice and are present in an atomic or molecular compound. During this reaction process, the organic acid begins to react with the inorganic acid. This results in an oxidation or reduction of the heavy metal compounds to the metal.

According to the invention the ligand material, e.g.

Magnetite, pyrite burnup, blast furnace slag, fly ash or lava are tribochemically treated by an appropriate mill. It was found that the finer the grain size, the more effective the reaction. The material should therefore be ground to at least a grain size of less than 0.1 mm, most preferably about 0.07 mm.

: This ground ligand material is mixed with a mixture of a soft organic acid (e.g. formic acid, acetic acid, propionic acid, citric acid, malic acid) and an inorganic acid (e.g. nitric acid, hydrochloric acid, sulfuric acid). The mixing ratio of the organic acid to the inorganic acid is 1: 3, a volume ratio of 32:68 is preferred. The ratio of ligand material to acid is 0.5 to 1: 3. The ratio 1: 2 is preferred.

The acid mixture must be freshly prepared and used immediately, as it reacts violently with itself after approx. 1 hour. The acid mixture is added with stirring at room temperature and heated to approximately 50 ° C. to accelerate the reaction. As soon as the reaction starts, it is very violent. This violent reaction subsides after about 20 - 30 minutes. The mixture continues to react slowly for about another 2 hours. A large thermal development occurs during the first reaction and the mixture heats up to 150 ° C. As already indicated above, the reaction time is; - 4 - <* depending on the fineness of the grain of the ligand material.

The acid mixture used can also influence the reaction time.

After the reaction, the stirring is stopped. Two layers are formed in the reaction vessel, a liquid and an insoluble layer. The liquid layer has a characteristic color, which can vary between money and dark red. The liquid is poured off and filtered.

The liquid obtained, the volume of which is considerably smaller than the initial volume of the acids, reacts strongly acidic * (pH 2.0).

After testing in the atomic absorption spectroscope (AAS), the liquid shows a share of gold (2-8 ppm), platinum (0.5 - 7 ppm) and ruthenium (36 ppm) in addition to iron, copper and manganese. These metal contents can be extracted by conventional methods (e.g. electrolysis or the like).

The solid, insoluble residue is mixed with water in a ratio of 1: 2 and washed. The water takes on a dark yellow color within 30 minutes. The wash water is filtered and measured in the AAS. Levels of gold (approx. 2 ppm), platinum (, 2 - 1.2 ppm) and ruthenium (10 ppm) can still be measured by the AAS.

The undissolved residue is dried. Even when wet, smaller and larger precious metal particles can be seen with the naked eye. These are extracted by conventional methods (magnetic separation, cyanide leaching, thiourea leaching, etc.).

example

Magnetite was used as the ligand material, the iron oxide content of which was approximately 75%. The magnetite contained approximately 6% silicates (andradite), as secondary elements sodium, magnesium,

T

'- 5 - t

Aluminum, silicon, phosphorus, sulfur, calcium, manganese, zinc, as well as traces of potassium, titanium, cobalt and copper. Furthermore, by comparison samples from the material in the AAS gold, silver, platinum, palladium, osmium, iridium, rhodium, ruthenium,

Rhenium, gallium, vanadium and lutetium can be detected.

The magnetite was ground to a grain size of approximately 0.07 mm.

In a 5 1 thick-walled beaker, 150 g of the raw material were mixed with a mixture of 130 parts by volume of 98% formic acid and 170 parts by volume of 65% nitric acid with stirring at room temperature. We have given the acid mixture, which has a pH value of -0.6, the name sitaric acid. Then the magnetic stirrer was heated to approx. 50 ° C and within 5 minutes there was an extremely violent reaction accompanied by an extremely strong smoke development and an exothermic reaction. The liquid heated up to approximately 200 ° C. This strong reaction subsided after about 15 minutes, but the mixture continued to react for about 2 hours.

The liquid that had turned deep dark red was poured off from the solid residue and filtered. The liquid volume of around 300 ml at the start of the reaction had been reduced to around 120 ml. The pH of the liquid was pH 2.0.

The acidic liquid was checked with the AAS and contents of gold, platinum, ruthenium and osmium were detected.

The solid, undissolved residue was distilled with 300 ml. Washed out water and filtered. The wash water was fed to the AAS for testing and platinum, palladium, gold, ruthenium and osmium could be detected.

The insoluble residue was dried and ground again and finely distributed on a glass plate. A magnet was inserted under the glass plate to separate the iron from andradite and the visible, yellow and silvery shiny metal particles - as far as it was possible under these primitive conditions.

- 6 - * The remaining andradite metal particles residue, which was still contaminated with black magnetite particles, was collected doci-mastically via lead smoothing in the melting furnace at 1,000 ° C. The lead king (Regulus) obtained was dissolved in dilute nitric acid. An insoluble residue remained. The part dissolved in the dilute nitric acid was filtered off and the filtrate was fed to the AAS for testing. This resulted in a yield, extrapolated to a metric ton, of: 93 grams of gold 700 grams of platinum 1,800 grams of ruthenium 28 grams of palladium 8 grams of silver 12 grams of osmium

The rhodium and iridium content could not be measured due to the lack of equipment.

Further experiments were carried out with pyrite combustion. The

Results there - extrapolated to one metric ton - were 31 grams of gold, 350 grams of platinum, 400 grams of ruthenium, 2 grams of silver, and 8 grams of osmium

Experiments with a mixture of acetic acid / nitric acid have also been successful, but the mixture of formic acid / nitric acid has proven to be more favorable.

Experiments were also carried out with a material which had a grain size of approximately 2 mm. Here, too, the same results were achieved, but the reaction time was 30% higher with respect to a material with a grain size of about 0.07 mm.

The present invention thus describes an economical process for the extraction of rare and expensive heavy metals from ligand materials previously considered to be worthless.

Claims (15)

1. A method for breaking crystal lattice of ligand material, characterized in that tribochemically treated (ground) ligand material is mixed with a mixture of an organic and an inorganic acid at room temperature with stirring. 2. The method according to claim 1, characterized in that an acid mixture with a theoretically high hydrogen release and a theoretically high reducibility is used by the organic / inorganic acid mixture. 3. The method according to any one of claims 1 to 2, characterized in that formic acid is used as organic acid and nitric acid is used as inorganic acid. 4. The method according to any one of claims 1 and 2, characterized in that acetic acid is used as the organic acid and nitric acid is used as the inorganic acid. 5. The method according to any one of claims 1 to 4, characterized in that the ligand material is ground to a grain size of less than 0.1 mm. : 6. Process --- for the production of heavy metals from ligand material and pyrites according to the process of one of claims 1 to 5, characterized by adding a mixture of organic and inorganic acid to the ligand material at room temperature with stirring, stirring the reaction mixture for 1 up to 2 hours, separation of the liquid from an insoluble residue, isolation of the heavy metals from the liquid by conventional methods, for example electrolysis 7. A process for the extraction of heavy metals from ligand material and pyrites according to claim 6, characterized by washing the insoluble residue with water at room temperature with stirring. Processing of the washing liquid by known electrolysis or electrochemical processes for the extraction of heavy metals. 8. A method for obtaining heavy metals from ligand material and pyrites according to claim 6, characterized by drying and grinding the insoluble residue, separating the heavy metals by magnetic separators. ψ t / t ί - 8 - Processing of the separated precious and heavy metals by conventional methods (e.g. melting or dissolving and electrolyzing) 9. The method according to any one of claims 6 to 8, characterized in that the organic acid is mixed with the inorganic acid in a ratio of 1: 3. 10. The method according to any one of claims 6 to 8, characterized in that the ligand material or pyrite and the mixture of inorganic / organic acid in the ratio tg / ml) 1: 0.5 to 1: 3 are used. 11. The method according to any one of claims 7 or 8, characterized in that the insoluble residue is mixed with water in a ratio of 1: 2. 12. The method according to claims 6 to 10, characterized in that the heavy metals remaining in the residue by conventional magnetic separation, melting process, cyanide leaching and the like. be isolated. 13. The method according to any one of claims 6 to 12, characterized in that the ligand material is selected from iron oxides, blast furnace slag, fly ash, pyrites or lava. 14. The method according to claim 13, characterized in that magnetite is used as ligand material. 15. The method according to claim 13, characterized in that pyrite burnup is used as ligand material.