JP2014500142A - Magnetic recovery of valuables from slag materials - Google Patents

Abstract

  The present invention includes at least one of step (A) pulverizing slag, (B) optionally at least one magnetic particle and / or at least one surface active material, optionally pulverized slag of step (A). Contacting in the presence of a dispersant resulting in the formation of an aggregate of at least one metal and at least one magnetic particle, (C) optionally adding at least one dispersant to the mixture obtained in step (B) At least one metal and other components comprising: obtaining a dispersion having a suitable concentration; and (D) separating the agglomerates from the mixture of step (B) or (C) by application of a magnetic field And the use of at least one magnetic particle for the separation of slag.

Description

  The present invention comprises at least step (A) a step of pulverizing slag to obtain particles, (B) optionally pulverizing slag of step (A) and at least one magnetic particle and / or at least one surface modifying substance. Contacting, optionally in the presence of at least one dispersant, resulting in the formation of aggregates of at least one metal and at least one magnetic particle by magnetic and / or hydrophobic interaction, (C) optionally at least one Adding a dispersant to the mixture obtained in step (B) to obtain a dispersion having a suitable concentration, and (D) applying particles from the mixture of step (A) by applying a magnetic field or step (B) Or a method for separating at least one metal from a slag comprising at least one metal and other components, comprising separating the agglomerates from the mixture of (C), and a slag It relates to the use of at least one magnetic particles for grayed separation.

  In particular, the present invention relates to the processing of naturally occurring ores containing materials obtained from, for example, processes, advantageously chemical processes, or autocatalysts, or other industrial processes, or existing PGM (Platinum Group Metals: For the separation of noble or base metals from slags obtained from platinum group metals), in which slags containing several valuables, such as PGM, Cu, Mo, Co, Zn, Mn, Ni or others, Manufactured.

  For example, industrial precious metals, Pt, Pd and Rh play an increasingly important role in society. Their applications vary from chemical reaction catalysts to air gaps, and due to their chemical and physical properties, and these metals today are responsible for the environment in almost every aspect of our lives, for example in computers or drugs. It exists to maintain and improve lives. One industrial application of precious metals is for homogeneous or heterogeneous catalysts, in particular environmental catalysts such as three-way catalytic converters or diesel oxidation catalysts, or for high performance materials such as turbine blades, or in recent years Used for jewelry and coin making.

  The high demands of various precious and base metals recycle industrial precious metals Pt, Pd, Ph that are combined, for example, in automotive converters. After rough prescreening and precollapse, the spent catalyst is smelted in an arc furnace. At about 1800 ° C., the metal may be separated from other materials such as silica, alumina, ceria, and the like.

  Smelting recirculation is not always carried out in an arc furnace or induction furnace. In the case of recirculation of materials with so-called base metals such as Cu, Mo, Zn, Co, Ni, etc., the flash furnace operates at a considerably lower temperature, for example just above the melting point of the metal that needs to be recovered. Is used. In general, smelting methods such as temperature, additives, such as collected material, such as magnetite, are known to those skilled in the art.

The remaining material obtained after removal of valuables is commonly referred to as blast furnace slag. The slag material typically large amounts of silicates, and other ^{Al -, Ce -, Zr -} , Fe - oxides, and the like, and also includes a small amount of sulfide. After cooling, a very hard material is obtained, sometimes containing a significant amount of valuables.

  There is a strong tendency to recover residual metals from this slag by re-smelting the material or by flotation.

  Re-smelting of slag material requires very high energy, because the whole slag material needs to be fed again into the furnace, whereas the concentration of valuables is 1-100 ppm Because it is a range or even higher in certain cases. Furthermore, the smelting conditions need to be adjusted to the specific composition of the slag material. Therefore, pre-concentration of valuables from slag is preferred.

  Prior art methods are based on the beneficiation of valuables using flotation. Here, the valuables are selectively hydrophobized in the presence of undesirable materials. Due to their hydrophobic shell, these valuables tend to adhere to the bubbles in an aqueous system and can be transported to the top with it and recovered. In the case of slag, especially blast furnace slag, this technology cannot be applied efficiently. By the smelting method, the metal is finely distributed and highly crystallized. Valuables thus occur as extremely dense particles with disadvantageous flotation properties, especially in combination with the degree of grinding required for the release of the particles. Thus, flotation is rarely an economically successful way to recover residual valuables from slag.

  Another approach to recovering residual metal is the leaching method. Here, the entire matrix or at least the valuables therein are dissolved in highly concentrated acid or base. This solution is treated chemically or electrochemically to recover valuables. This approach consumes large amounts of chemicals and, therefore, is rarely an economically viable method for recycling precious metals or non-metals, like flotation.

  An alternative approach for residual metal recovery is magnetic separation. Magnetically assisted separation can use magnetic particles as a carrier that is dense compared to bubbles and can transport very fine materials particularly efficiently.

  Regarding the magnetic separation technology, there are several prior arts.

  WO 02/0066168 A1 relates to a method for separating ores from mixtures containing ores, suspensions or slurries of these mixtures can be treated with particles that are magnetic or can be floated in aqueous solution. A magnetic field is applied after the addition of magnetic particles and / or particles capable of flotation, so that agglomerates are separated from the mixture. However, the degree to which the magnetic particles are bound to the ore and the strength of the bond is not sufficient for a method to be performed with a sufficiently high yield and effectiveness. The separation of metal from slag is not disclosed.

  US 4,657,666 discloses a method for enrichment of ore, wherein the ore present in the gangue is treated with magnetic particles so that aggregates are formed by hydrophobic interactions. The Magnetic particles are hydrophobized on the surface by treatment with a hydrophobic compound, resulting in adhesion to the ore. Aggregates are then separated from the mixture by a magnetic field. The cited literature also discloses that the ore is treated with a surface active solution of 1% sodium ethyl xanthogenate before adding the magnetic particles. In this method, the separation of ore and magnetic particles is brought about by the destruction of surface-active substances added to the ore in the form of a surface-active solution. The separation of metals from slag is not disclosed in the document.

  WO 2010/100180 A1 describes at least one particle P hydrophobized on its surface with at least one first surface modifying substance and hydrophobic on its surface with at least one second surface modifying substance The present invention relates to aggregates of at least one magnetic particle MP, a method for producing the aggregates, and the use of the aggregates to separate the particles P from a mixture comprising the particles P and other components. A method for separation from smelting slag is not disclosed in this document.

  WO 2010/097361 A1 describes a method for separating at least one first material from a mixture comprising the at least one first material, at least one second material and at least one third material. The mixture to be treated is first contacted with at least one hydrocarbon in an amount of 0.01 to 0.4% by weight, based on the sum of the mixture and at least one hydrocarbon, Further contacting the at least one hydrophobic magnetic particle to agglomerate the magnetic particle and at least one first material, and separate the agglomerate from the at least second material and at least the third material by applying a magnetic field. And optionally, at least the first material is subsequently separated from the magnetic particles, preferably quantitatively, wherein the magnetic particles are preferably separated into the process. Can be recirculated. A method for separation from smelting slag is not disclosed in this document.

  WO 2010/066770 A1 contains at least one first material, at least one first material and at least a second material in an amount of 0.001 to 1.0% by weight relative to the total of the mixture. Disclosed is a method for separating from a mixture comprising: first contacting a first material with a surface modifier to first hydrophobize and contacting the mixture with at least one magnetic particle. Agglomerating the magnetic particles and the hydrophobized first material and separating the agglomerate from the at least one second material by application of a magnetic field, and the at least first material is advantageously quantitative In addition, it can be separated from the magnetic particles, in which case the magnetic particles can advantageously be recycled to the process. A method for separation from smelting slag is not disclosed in this document.

  WO 2010/007157 A1 discloses a method of separating at least a first material from a mixture comprising this at least a first material and at least a second material, wherein the mixture to be separated is first In contact with at least one selective hydrophobic agent to form an adduct from at least one hydrophobic agent and at least one first material, and the adduct has at least a LCST (Lower Critical Solution Temperature). In one polymer compound, the adduct and at least one functionalized magnetic particle are agglomerated by contacting with at least one magnetic particle functionalized on the surface at a temperature at which the polymer compound has hydrophobic properties. Separating the objects by the application of a magnetic field and subsequently curing the agglomerates at a temperature at which the polymer compound has hydrophilic properties. Separate by. A method for separation from smelting slag is not disclosed in this document.

  WO 2010/007075 A1 relates to a method for separating at least one first material from a mixture comprising this at least one first material and at least one second material, wherein the mixture to be separated is In contact with at least one bifunctional compound and at least one magnetic particle to form an adduct from at least one first material, bifunctional compound and at least one magnetic particle, the adduct being suitable Dispersed in the suspending medium, the adduct is separated by application of a magnetic field, and the separated adduct is suitably separated by a suitable metric method to obtain at least a first material. A method for separation from smelting slag is not disclosed in this document.

  WO 2009/065802 A2 relates to a method for separating at least one first material from a mixture comprising this at least one first material and at least one second material, in a suitable suspension medium First producing a suspension of a mixture comprising at least one first material and at least one second material and at least one magnetic material, wherein the pH of the suspension is adjusted to at least one first material. And at least one magnetic material is set to a value having an opposite surface charge to agglomerate them, the agglomerates obtained in this way are separated by application of a magnetic field gradient, and the separated agglomerates are at least 1 The first material and the at least one magnetic particle are separated by setting the pH to a value having the same surface charge to obtain at least the first material. A method for separation from smelting slag is not disclosed in this document.

  Said document advantageously discloses various methods for separating valuables from naturally occurring ores. No method for the efficient separation of metals, especially precious metals, from slag has been disclosed in the prior art.

  The object of the present invention is therefore to provide a method by which at least one metal, preferably at least one noble or base metal, can be efficiently separated from the slag.

  Furthermore, the object of the present invention is to subject the precursor of the metal to be separated obtained from the process according to the invention, for example a magnetic agglomerate comprising the metal to be separated and magnetic particles, directly to further processing and to obtain pure It is to provide a method by which the desired metal can be obtained in the form. Extra addition or removal of iron-containing compounds, substantial magnetic compounds, may be avoided or reduced.

  Another object of the present invention is to provide a method for separating at least one metal from a slag material, wherein the magnetic component already present in the slag to be separated and associated with the at least one metal is Collected using a suitable time separator.

These subjects are at least the next step (A) a step of pulverizing slag to obtain particles,
(B) Optionally, the ground slag of step (A) is contacted with at least one magnetic particle and / or at least one surface modifying material, optionally in the presence of at least one dispersant, to provide magnetic and / or hydrophobic properties. Resulting in the formation of aggregates of at least one metal and at least one magnetic particle by sexual interaction;
(C) optionally adding at least one dispersant to the mixture obtained in step (A) or (B) to obtain a dispersion with a suitable concentration, and (D) applying a magnetic field to the step ( Separating at least one metal from a slag comprising at least one metal and other components comprising separating particles from the mixture of A) or agglomerates from the mixture of steps (A), (B) or (C) This is solved by the present invention which is a method for achieving this.

  A very distinct feature of the method according to the invention is that the magnetic particles are used to recover valuables from smelting slag by magnetic separation. In general, smelting methods for enriching noble metals or base metals are carried out using mixtures or aggregates of these noble metals or base metals and iron-containing compounds. With regard to the process according to the invention, it is advantageous to obtain particles or agglomerates comprising iron-containing compounds such as magnetite and the metal after magnetic separation. These particles or agglomerates may be used directly in a smelting process to obtain a noble metal in a form that can be fed into a refiner. After smelting, beneficiation with precious metals generally needs to be refined to obtain pure metals. With respect to the process according to the invention, other steps can be avoided, for example separating particles or agglomerates after magnetic separation, and / or adding extra iron-containing compounds before smelting: obtained in the present invention. The magnetite used as a carrier within the process can be adjusted to a composition for the smelting process. With the process according to the invention, iron-containing particles or agglomerates are obtained that carry the appropriate and advantageous amount of iron necessary to obtain the metal in pure form by smelting. The method according to the invention then combines two method steps, the step of magnetically oreminating the residual noble metal from the smelting slag material and the step of adding a collector necessary for an efficient smelting method. This combination is unique and has not been described in any literature.

  Furthermore, with regard to the method according to the invention, a magnetic material already present in the slag to be separated and associated with the desired at least one metal is used to obtain at least one metal by magnetic separation.

  The method according to the invention is carried out to separate at least one metal from any slag, such as smelting slag, blast furnace slag or other slag material. Slag can be defined as a product from a second method from a metallurgical method or a residue from a combustion method.

  The single step of the preferred embodiment of the single component in general and used according to the present invention and of the method present in the method according to the present invention is described in detail below.

  The process according to the invention is carried out for separating slag, for example smelting slag or blast furnace slag. These materials are generally known to those skilled in the art.

  In a preferred embodiment, the slag treated according to the present invention is selected from blast furnace slag obtained, for example, from the processing of minerals from platinum group metals (PGM) with ore, and catalytic materials or mixtures thereof are used. .

  In a preferred embodiment of the method according to the invention, the slag introduced during step (A) is an artificially produced slag. The slag introduced in step (A) of the process according to the invention is advantageously not naturally occurring like ore, but is produced artificially.

  The invention therefore advantageously relates to a method according to the invention, wherein the slag introduced in step (A) is an artificially produced slag.

  The main use of smelting methods is the ore or scrap or material mixture containing various metals, the desired metal is skimmed as a metal layer, and the undesired metal oxides such as silicate, alumina etc. are slag Is to convert it into a remaining form. In general, oxidation and reduction smelting operations can be identified. The slag material to be separated according to the invention is obtained under reduced conditions or obtained under oxidized conditions.

  For example, slag produced in PGM recovery operations, such as Pt mines, reprocessing of old catalysts, etc., is typically formed under reducing conditions that will now be described by way of example. The energy required to heat the mass to above the melting point is generally provided by external heat, such as a gas burner, or arc. Often carbon or other reducing material is added. The objective is to reduce the noble metal compound to the metallic state. The reduced metal and oxide layers are immiscible and cannot be mixed. Slag produced under reduced conditions often contains residual PGM as an alloy with free metals or other transition metals, especially iron. These alloys are often ferromagnetic and can be separated from the slag matrix after release by a magnetic field. The loss of PGM into the slag is almost exclusively due to incomplete demixing of the liquid metal or liquid slag phase. It does not matter that the formation of a PGM solid solution in the slag occurs.

In smelting operated under reduced conditions, most base metal sulfides remain as sulfides. Some metal species, such as noble metals, may remain as natural metals or tend to migrate into magnetic debris. Magnetite is often fed into the smelter and supports slag formation. Platinum and rhodium advantageously feature this behavior of moving to magnetic debris. Thus, after the smelting process, this noble metal is hidden as a dopant in the magnetic debris, preferably in the slag. In this overview, the magnetic separation method according to the invention may be used directly without any additional steps. The final operation depends on the composition of the slag, for example:
(1) In the case of Pt, Rh is the most interesting metal and magnetite is fed into the smelter and more than normally pure magnetite separation without the addition of additional magnetite after grinding step (A) Enough to restore the value of the metal.
(2) In the case of Ni, Cu and other base metals are the most interesting metals, and surface modifying compounds for metal sulfides are preferably xanthan, dithiophosphate or carbamates according to general formula (I) Added to hydrophobize these species. In the next step, hydrophobized magnetite is added to form hydrophobic aggregates. Due to its magnetism, magnetite and metal sulfides containing these hydrophobic aggregates may be magnetically separated. In this case, the scavenger and the hydrophobic magnetite are advantageously added after the grinding step (A) but before the magnetic separation step (D).
(3) If the interesting metals are precious and base metals, these two summaries from (1) and (2) can be combined to provide the operation described in (2).

  In smelting operated under oxidizing conditions, base metal sulfides and some natural metal compounds are oxidized. In this case, only the magnetic particle separation method according to the invention may be used exceptionally without pretreatment. However, the magnetic separation method according to the present invention may be used as described herein when performing surface treatments such as selective sulfidation of valuable desired metals. In addition to the preferred sulfurization, other surface treatments may also be used to convert the desired metal species to sulfide, natural or magnetic form. These treatments are known to those skilled in the art.

  Another aspect that may affect the process for separating at least one metal from the slag according to the invention is that the process steps to be introduced in a particularly preferred embodiment are how the slag material is treated after smelting. , Especially how to cool.

  Generally, after reduction or oxidative smelting, the metal phase is scraped and the slag is further processed, for example by granulation. Prior to the next step, in particular the step of the method according to the invention requires the slag to be cooled.

  In the first embodiment, various discrete domains of various compositions are advantageously formed when the slag is exposed to room temperature for a long time, for example several days, for cooling. These various domains may be detected by methods known to those skilled in the art, for example using X-ray based methods such as SEM. By this method, heavy elements can be detected as bright spots that are buried mainly in an oxide matrix containing, for example, Mg, Al, Si, O.

  The size of the domain may be influenced by the cooling time, for example. According to the first embodiment of the invention, the domains can grow and form domains in the micrometer range for slag that has been cooled to room temperature without any other influences such as addition of water. This embodiment may introduce a particularly preferred method according to the preferred variants 1 or 2 described below. In general, when the slag is slowly cooled, the domain becomes large, and is also a domain containing, for example, magnetite. As mentioned above, the domain containing magnetite also features some precious metals. These larger magnetic domains can more easily be separated by magnetic separation according to variant 1 or 2 described below. The lower limit of the size of the magnetic domain for this embodiment is, for example, 1 μm.

  In a second embodiment, the slag is cooled (quenched) very rapidly after smelting, for example by contact with water, for example by transferring the slag into a concrete container with water. With this embodiment, the domains are not grown and the resulting slag is very close to the solid solution and the various metals and elements do not form very separate domains.

  When the slag is produced according to this second embodiment, the separation method according to the invention may be used in particular according to the preferred variants 2 or 3 described below.

  The slag used in the process according to the invention, preferably the blast furnace slag, is advantageously obtained by a smelting method known to those skilled in the art, for example metals such as Mo, Cu, Ni, Ag, Hg, Au, Pt. , Pd, Rh, Ru, Ir, Os or mixtures thereof. For example, arc smelting is used in these furnaces and is further used in methods such as scrap iron smelting.

  In a preferred embodiment, the at least one metal to be separated from the slag according to the invention is Ag, Au, Pt, Pd, Rh, Ru, Ir, Os, Cu, Mo, Ni, Mn, Zn, Pb, Te , Sn, Hg, Re, V, Fe, and mixtures thereof. Primarily, these metals may be present in elemental form or as a mixture, for example in oxidized and sulfided form, as components in binary or multimetallic compounds. In another embodiment of the present invention, the noble metal may be a metal compound, such as an alloy of another metal, such as Fe, Cu, Ni, Pb, Bi, and / or a non-metal, such as phosphide, arsenide. , Sulfides, selenides, tellurides and the like. Particularly preferred metal compounds are metal alloys.

  The present invention thus provides that at least one metal is Ag, Au, Pt, Pd, Rh, Ru, Ir, Os, Cu, Mo, Ni, Mn, Zn, Pb, Te, Sn, Hg, Re, V and It relates to a process according to the invention, selected from the group consisting of their mixtures, for example with one another or with their elements, for example Fe, Ni, Pd, etc.

  Advantageously, the invention relates to a method according to the invention, wherein at least one metal is selected from PGM, wherein the PGM is Au, Pt, Ir, Pd, Os, Ag, Hg, Rh, Ru, in particular Au, Pt, Pd, Rh, more preferably abbreviations for noble metals such as Pt, Pd, Rh.

  Advantageously, the blast furnace slag used in the process according to the invention is obtained as a product of a smelting process, for example as a final product, by-product and / or waste product. During smelting, the silicate-rich liquid phase is separated from the heavy metal melt. The latter flows through a dedicated opening in the melting vessel and is further processed. The phase separation is not complete, however, and the desired metal debris becomes trapped in the liquid slag phase and remains dispersed after solidification resulting in a so-called mixed layer. In a preferred embodiment of the invention, the smelting slag obtained from this mixed layer is advantageously treated by the method according to the invention.

In a preferred embodiment of the invention, the slag used, preferably the blast furnace slag, is a solid solution and is advantageously SiO ₂ , CaO, Al ₂ O ₃ , MgO, P ₂ O ₃ , ZrO _2. Fe ₂ O ₃ , Fe ₃ O ₄ , CeO ₂ , Cr ₂ O ₃ , their complex oxide matrix and other components selected from the group consisting of mixtures. These oxides need not be present in the slag matrix as isolated compounds, but may be present only as complex oxides. It is common to show mixed metal oxides composed of binary oxides of the respective metals. This nomenclature may be used in the description. The solid solution may be amorphous and / or glassy, or may include a crystalline material composed of the metal oxide.

A very typical composition of blast furnace slag that can be used with particular preference in the process according to the invention is 5 to 80% by weight of SiO ₂ , 20 to 50% by weight of CaO, 0 to 60% by weight of Al ₂ O. ₃ , 0-10 wt% MgO, 0-10 wt% P ₂ O ₅ , 0-10 wt% ZrO ₂ , 0-10 wt% Fe ₂ O ₃ , and optionally other iron oxides, 0 10 wt% of CeO _2, and optionally contain other ingredients.

The present invention thus advantageously relates to the aforementioned method, whereby the _{slag, SiO 2, CaO, Al 2} O 3, MgO, P 2 O 3, ZrO 2, Fe 2 O 3, Fe 3 O 4, And at least one compound selected from the group consisting of CeO ₂ , Cr ₂ O ₃ , composite oxide matrices and mixtures thereof.

  The other components present in the slag separated according to the invention are obtained after the corresponding precursor smelting process. The difference between the slag separated according to the invention and the naturally occurring ore is that the slag according to the invention is not obtained from natural sources but is obtained from an artificial process.

  In addition to said compounds, the slag to be treated according to the invention may contain other components, for example compounds containing lead and / or iron and / or lead and / or iron in metallic form. In a preferred embodiment, iron-containing compounds such as magnetite are present in the slag to be separated. In this preferred embodiment, step (B) of the method according to the invention may be skipped and the desired at least one metal is magnetically as an agglomerate with a magnetic component already present in the slag. To be separated.

  The slag to be treated with the process according to the invention comprises at least one metal, in particular the preferred metal, in an amount of 0.01 to 1000 g / t, preferably 0.01 to 500 g / t of slag. Slag materials containing small or large amounts of the desired at least one metal are also within the scope of the present invention.

  In a first preferred embodiment of the invention, the at least one metal to be separated from the slag is present in an amount of 0.01 to 1000 g / t (slag), and the at least one metal is a noble metal, such as Ag. , Au, Pt, Pd, Rh, Ru, Ir, Os, Zn, Pb, Te, Sn, Hg, Re, V or Fe and / or Cu, Mo, Ni and Mn or other base metal sulfides Is done. Slag materials containing small or large amounts of the desired at least one metal are also within the scope of the present invention.

  The individual steps of the method of the invention are described in detail below.

Step (A):
The essential step (A) of the method according to the invention comprises grinding the slag to obtain particles.

  In step (A) of the method according to the invention, slag obtained from generally known smelting methods is preferably pulverized to obtain slag particles having a particle size suitable for other method steps.

In a preferred embodiment of the process of the present invention, obtained by crushing the slag to be processed by the present invention, d ₈₀ less than 100 [mu] m, for example, particles having a d ₈₀ of 100 nm to 100 m. The term “d ₈₀ ” is generally known to those skilled in the art and means that 80% of the particles present in the mixture have a diameter less than the above.

The invention thus relates to the process of the invention, wherein in step (A) the slag is ground to d ₈₀ of less than 100 μm.

  In a preferred embodiment, step (A) is performed by milling, in particular ball milling. Suitable methods and equipment are generally known to those skilled in the art, for example, stirring or wet milling in a rotating ball mill.

  In another preferred embodiment, the particles are screened into debris having the desired particle size after milling and the oversized debris is optionally returned to the milling process.

  The grinding according to step (A) of the process according to the invention may be carried out in the presence or absence of at least one dispersion medium. Suitable dispersion media for dispersion are selected, for example, from the group consisting of water, water-soluble organic compounds and mixtures thereof, with water being particularly preferred. If step (A) is introduced during the dispersion, it is preferred to use the same dispersion medium used in the overall process, preferably water.

  In one embodiment of the method according to the invention, step (B) is introduced after step (A). In this case, steps (A) and (B) are introduced at least partly at the same time, for example the slag to be separated according to the invention is at least one surface modifying substance and / or at least one during milling. Can be in contact with two magnetic particles. Details of this preferred embodiment are given below.

  In another preferred embodiment of the process according to the invention, step (B) is not introduced after step (A). This embodiment is preferred when the slag to be treated according to the invention itself contains a magnetic material, and after grinding, magnetic particles containing the desired metal and magnetic material are obtained. According to this embodiment, no further magnetic particles and / or surface modifying substances need be added.

  In one particularly preferred embodiment of the process according to the invention, after step (A), at least one dispersant is added to the mixture obtained in step (A) to obtain a dispersion having a suitable concentration. According to the present invention, this optional step is referred to as step (A1).

Thus, in particular, the present invention comprises the step of (A1) adding at least one dispersant to the mixture obtained in step (A) after step (A) to obtain a dispersion having a suitable concentration. It relates to a method according to the invention in which step (A1) is carried out.

  Step (A1) is advantageously carried out when step (A) of the method according to the invention is carried out in bulk.

  Step (A1) is advantageously carried out when non-hydrophobized magnetite is added to step (B). According to this embodiment, step (C) of the method according to the invention is not advantageously carried out.

  Suitable dispersion media are all the dispersion media mentioned above for step (A). A particularly preferred dispersion medium added in step (A1) of the process according to the invention is water, optionally mixed with at least one polar organic solvent mentioned for step (A).

  Thus, step (A1) converts the mixture present in bulk from step (A) into a dispersion or reduces the concentration of the mixture already present in the dispersion from step (A) by adding a dispersion medium. Conversion to a dispersion.

  According to the present invention, the amount of dispersion medium added in step (A1) may generally be selected so as to obtain a dispersion that can be easily stirred and / or transported.

  In a preferred embodiment, the amount of dispersion medium added in step (A1) of the process according to the invention is from 1 to 80% by weight, preferably from 10 to 45% by weight, based on the total amount of solids to be dispersed respectively. %, In particular to obtain a dispersion having a solids content of 30 to 40% by weight.

  The addition of the dispersion medium in step (A1) of the present invention may be carried out according to the present invention by all methods known to those skilled in the art.

Step (B):
Step (B) of the method according to the invention is an optional step.

  In a preferred embodiment, step (B) is not carried out and is skipped. In this embodiment, the slag to be separated is ground in step (A) to obtain particles, optionally at least one dispersant is added in optional step (C), and the particles are added in step (D). ) Magnetically separated. Step (B) may be skipped if magnetic particles that are correlated with the desired at least one metal are present in the slag to be separated. In this case, no further magnetic particles and / or surface modifying substances are added (variant 1). This embodiment of the method according to the invention is advantageously carried out when the slag obtained by slow cooling and thus containing slag containing domains of magnetic particles is separated according to the invention. This preferred method according to the invention comprises steps (A), (C) and (D).

  In another preferred embodiment, it is further possible to carry out step (B), but the magnetic particles are separated if the magnetic susceptibility of the magnetic particles present in the slag is not effectively separated sufficiently by the magnetic field gradient. Exists in the slag to be done. Magnetite particles are then added. Due to the magnetic-magnetic interaction, stronger magnetism is achieved with the original very weak magnetic particles that can be magnetically separated. In this embodiment, advantageously no surface-modifying substance needs to be added (variant 2). This embodiment of the process according to the invention is advantageously carried out when it is obtained by rapidly cooling (quenching) the slag produced under reducing conditions. This further preferred method according to the invention comprises steps (A), (A1), (B) and (D).

  In another preferred embodiment of the method according to the invention, step (B) is carried out when the slag to be separated does not have magnetic particles or not enough magnetic particles around the valuables. In this case, at least one surface modifier is added in step (B) of the method according to the invention to hydrophobize at least one metal in the presence of other components desired. Further, hydrophobized magnetic particles are added. In another embodiment, non-hydrophobized magnetic particles are added in combination with at least one compound for hydrophobizing the magnetic particles to attach to the surface of the magnetic particles and become hydrophobic in situ. Due to the hydrophobic interaction between the hydrophobized at least one metal and the hydrophobized magnetic particles, the hydrophobized magnetic particles stick to the hydrophobized at least one metal. These hydrophobic aggregates may be separated magnetically (variant 3). This embodiment of the process according to the invention is advantageously carried out when obtained by rapid cooling, for example by addition of water to hot slag. This further preferred method according to the invention comprises steps (A), (B), (C) and (D).

  Subsequently, an embodiment in which the step (B) is performed will be described below.

  Step (B) of the method according to the invention comprises contacting the ground slag of step (A) with at least one magnetic particle and / or at least one surface modifier, optionally in the presence of at least one dispersant, Including the formation of aggregates of at least one metal and at least one magnetic particle by magnetic and / or hydrophobic interactions. Magnetic particles present in the particles or agglomerates may be added in step (B) or already present in the slag to be separated.

  In a first preferred embodiment of step (B) of the method according to the invention, the ground slag obtained from step (A) of the method according to the invention is contacted with at least one surface modifier to give at least 1 One surface modifier is attached to the surface of at least one metal.

  The contact of the slag to be separated according to this first embodiment may be carried out in any suitable reactor known to those skilled in the art. In a preferred embodiment, this contacting is carried out in a mill, advantageously in a centrifugal, rotating or stirred ball mill, or in a T-tube, T-jet or Y-get. In a preferred embodiment, grinding to obtain a suitable particle size according to step (A) and adding at least one surface modifying substance simultaneously and / or in the same equipment, for example in the same mill Preferably in a continuous manner and optionally interrupted by sieving, for example by sieving or hydrocyclone.

  In an alternative embodiment, the contacting may be performed in an apparatus designed to use strong shear forces on the particles in suspension, such as a T-jet or Y-jet or T-tube.

  In a first preferred embodiment of step (B) of the method according to the invention, the ground slag obtained from step (A) of the method according to the invention is contacted with at least one surface modifier to give at least 1 One surface modifier is attached to the surface of at least one metal and is further contacted with at least magnetic particles that may optionally be hydrophobized at the surface.

  The contacting of the slag to be separated by this second embodiment may be carried out in any suitable reactor known to those skilled in the art. This contact is carried out in a mill, preferably in a centrifugal, rotating or stirred ball mill. In a preferred embodiment, grinding to obtain a suitable particle size according to step (A) and adding at least one surface modifying substance and at least one magnetic particle are the same simultaneously and / or sequentially. It takes place in the apparatus, for example in the same mill, preferably continuously and optionally interrupted by sieving, for example by sieving or hydrocyclone.

  In another preferred embodiment, at least one magnetic particle added in step (B) of the method according to the invention is hydrophobized. In a preferred embodiment of the method according to the invention, the compound required to hydrophobize at least one magnetic particle is obtained during grinding, before or after the addition of at least one magnetite and / or at least one surface. It is added before or after the addition of the modifying substance.

  In another embodiment of the method according to the invention, the compound for hydrophobizing at least one magnetic particle is not separated in step (B), although at least one magnetic particle is not added in step (B). Added if present in slag to be made. In this embodiment, at least one magnetic particle already present in the slag to be separated is hydrophobized.

  In a particularly preferred embodiment of the method according to the invention, the slag to be treated according to the invention simultaneously contacts at least one surface modifying substance and at least one hydrophobized magnetic particle. In another preferred embodiment, the magnetic particles are hydrophobized prior to contacting the slag to be treated with at least one surface modifying material.

  If at least one metal is hydrophobized using at least one surface modifying material, it is advantageous to use at least one magnetic particle that is also hydrophobized on its surface.

  By the method according to the invention, the terms “surface activity” and “surface modification” are used equivalently. For the purposes of the present invention, a “surface modifying substance” or “surface active substance” refers to the surface of a particle to be enriched, the presence of other particles that are not to be enriched, and then hydrophobicity due to hydrophobic interactions. Substances that can be modified in a way that causes adhesion of the conductive particles, preferably by making the surface of the first particles hydrophobic. Surface modifying materials that can be used in accordance with the present invention become attached to at least one metal, resulting in suitable hydrophobization of the at least one metal.

［式中、
Ａは、直鎖又は分枝鎖のＣ₁〜Ｃ₃₀−アルキル、Ｃ₁〜Ｃ₃₀−ヘテロアルキル、場合により置換されたＣ₆〜Ｃ₃₀−アリール、場合により置換されたＣ₆〜Ｃ₃₀−ヘテロアルキル、Ｃ₆〜Ｃ₃₀−アラルキルの中から選択され、
Ｚは、一般式（Ｉ）の化合物が少なくとも１つの疎水性材料に結合する基である］の表面改質物質の群から選択される。 Preferred surface modifying compounds for use in step (B) of the method according to the invention are attached to at least one first material of the general formula (I)

[Where:
A is, C ₁ -C ₃₀ linear or branched - alkyl, C ₁ -C ₃₀ - heteroalkyl, if C ₆ -C ₃₀ substituted by - aryl, C ₆ -C ₃₀ optionally substituted - is selected from aralkyl, - heteroalkyl, C ₆ -C ₃₀
Z is a group selected from the group of surface-modifying substances in which the compound of general formula (I) is a group that binds to at least one hydrophobic material.

In a particularly preferred embodiment, A is straight-chain or branched C ₄ -C ₁₂ -alkyl, more particularly preferably straight-chain C ₄ -alkyl or C ₈ -alkyl. The heteroatoms that may be present according to the invention are selected from among N, O, P, S and halogens such as F, CI, Br and I.

［式中、Ｘは、Ｏ、Ｓ、ＮＨ、ＣＨ₂からなる群から選択され、かつｎは０、１又は２である］のアニオン基、適宜、水素、ＮＲ₄ ⁺［式中Ｒ基は、それぞれ互いに独立して、水素又はＣ₁〜Ｃ₈−アルキル、アルカリ金属又はアルカリ土類金属である］から選択されるカチオンからなる群から選択される。挙げられたアニオン及び対応するカチオンは、本発明によって、一般式（Ｉ）の非電荷の化合物を形成する。 In another particularly preferred embodiment, X is

Wherein X is selected from the group consisting of O, S, NH, CH ₂ and n is 0, 1 or 2, optionally hydrogen, NR ₄ ⁺ [wherein the R group is Each independently of one another is selected from the group consisting of hydrogen or C ₁ -C ₈ -alkyl, alkali metal or alkaline earth metal]. The listed anions and the corresponding cations form according to the invention uncharged compounds of the general formula (I).

Particularly preferred surface modifying materials used in step (A) of the process of the invention are C ₁ -C ₂₀ -xanthan, such as octyl xanthan, C ₂ -C ₂₀ -dithiocarbamate or thionocarbamate, and C _1- C ₂₀ - is a dithiophosphate.

  The component A and / or the functional group Z that selectively adheres to at least one metal present in the slag to be separated may generally be selected from the above embodiments. In particular, the nature of the compound according to general formula (I) having a functional group Z is advantageously selected in relation to the nature of the slag, the nature and amount of the compound present in the slag.

  In a preferred embodiment, a mixture comprising one or more surface modifying compounds selected from compounds according to general formula (I) is used to modify the slag according to the invention. The composition of this mixture may usually be determined by one skilled in the art.

  The at least one magnetic particle used according to the invention is preferably an iron-containing compound, for example iron oxide. Suitable iron-containing magnetic compounds are generally known to those skilled in the art.

In a particularly preferred embodiment of the method according to the invention, the at least one magnetic particle is magnetic Fe ₃ O ₄ . In another embodiment of the invention, the at least one magnetic particle may be doped with at least one dopant. Suitable and preferred dopants are selected from the group consisting of Co, Ni, Zn and mixtures thereof. The at least one dopant is advantageously present in an amount of 0.1 to 5% by weight with respect to the at least one magnetic particle. One reason for the presence of at least one dopant is an increase in the magnetic properties of the magnetic material.

  Magnetite is known to those skilled in the art and is commercially available. Furthermore, methods for the production of magnetite are known to those skilled in the art. Furthermore, the positive influence of magnetite in the smelting method has been discussed above. However, the use of magnetite and smelting additives as scavengers for residual valuables is also discussed above.

The at least one magnetic particle used in accordance with the present invention is generally of an average diameter that can efficiently agglomerate the particle with at least one first material. In a preferred embodiment, the magnetic particles have a d ₈₀ of 1Nm～10mm. The particle size of magnetite may be reduced within the scope of grinding or milling methods.

  The advantage of using at least one iron-containing magnetic particle, preferably magnetite, is that after magnetic separation according to step (D) of the process according to the invention, an agglomerate comprising the desired at least one metal and iron-containing compound is obtained. And may advantageously be transferred directly to further smelting methods. In smelting methods to obtain noble metals, generally iron should be added to obtain noble metals with high purity. With respect to the present invention, the exact amount of iron to obtain high purity and yield can be easily adjusted.

  In a preferred embodiment, at least one magnetic particle is hydrophobized at the surface by at least one hydrophobic compound. As mentioned above, at least one hydrophobic compound may be added at any step of step (A) and / or (B) of the method according to the invention. In another embodiment, already hydrophobized magnetic particles may be introduced.

  The at least one magnetic particle that is already present in the slag to be separated and / or may be added in step (B) of the method according to the invention is such that the surface properties of the particles are such that the contact angle of the hydrophobized magnetic particles Is hydrophobized in a manner that is modified in a manner that is preferably greater than 30 °, preferably greater than 60 °, particularly preferably greater than 160 °.

［式中、
Ｂは、直鎖又は分枝鎖のＣ₂−又はＣ₃〜Ｃ₃₀−アルキル、Ｃ₂−又はＣ₃〜Ｃ₃₀−ヘテロアルキル、場合により置換されたＣ₆〜Ｃ₃₀−アリール、場合により置換されたＣ₆〜Ｃ₃₀−ヘテロアルキル、Ｃ₆〜Ｃ₃₀−アラルキルの中から選択され、かつ
Ｚは、一般式（ＩＩ）の化合物が少なくとも１つの磁気粒子に結合する基である］
の化合物の中から選択される。 Hydrophobic compounds for hydrophobizing at least one magnetic particle are preferably of the general formula (II)

[Where:
Of B, a straight-chain or branched C ₂ - or C ₃ -C ₃₀ - alkyl, C ₂ - or C ₃ -C ₃₀ - heteroalkyl, if C ₆ -C ₃₀ substituted by - aryl, optionally Selected from substituted C ₆ -C ₃₀ -heteroalkyl, C ₆ -C ₃₀ -aralkyl, and Z is a group to which the compound of general formula (II) binds to at least one magnetic particle]
Selected from the following compounds:

In a particularly preferred embodiment, B is straight-chain or branched C ₆ -C ₁₈ -alkyl, preferably C ₈ -C ₁₂ -alkyl, more particularly preferably straight-chain C ₁₂ -alkyl. . The heteroatoms that may be present according to the invention are selected from among N, O, P, S and halogens such as F, CI, Br and I.

［式中、Ｘは、Ｏ、Ｓ、ＮＨ、ＣＨ₂からなる群から選択され、かつｎは０、１又は２である］のアニオン基、並びに適宜、水素、ＮＲ₄ ⁺［式中Ｒ基は、それぞれ互いに独立して、水素又はＣ₁〜Ｃ₈−アルキル、アルカリ金属又はアルカリ土類金属又は亜鉛である］からなる群から選択されるカチオン、及び−（Ｘ）_n−Ｓｉ（ＯＺ）₃［式中ｎは０、１又は２であり、Ｚは荷電、水素又は短鎖アルキル基である］からなる群から選択される。 In another particularly preferred embodiment, Y is

[Wherein X is selected from the group consisting of O, S, NH, CH ₂ and n is 0, 1 or 2], and optionally hydrogen, NR ₄ ⁺ [wherein R group They are each independently of one another, hydrogen or C ₁ -C ₈ - alkyl, cation selected from the group consisting of an alkali metal or alkaline earth metal or zinc, and _{- (X) n -Si (OZ} ) _{3 wherein} n is 0, 1 or 2 and Z is a charged, hydrogen or short chain alkyl group.

［式中、ｎ、ｘ、ｙ及びｚは、互いに独立して１〜１００であり、かつＲは、互いに独立して、Ｃ₁〜Ｃ₁₂を有する直鎖又は分枝鎖のアルカリ基である］である。 Further preferred hydrophobic compounds are monosiloxanes, oligosiloxanes or polysiloxanes having free OH groups, such as

Wherein n, x, y and z are independently from each other 1 to 100, and R is independently from each other a linear or branched alkali group having C _{1 to} C _12. ].

In the formula (3), * means a bond to other components including —SiOR ₂ .

  More particularly preferred hydrophobizing substances of the general formula (II) are silicon-based, silicone oils, or siloxanes, phosphones, obtained, for example, from in situ hydrolysis of dodecylsiloxane or other alkyltrichlorosiloxanes or alkyltrialkoxysilanes. Acids such as octylphosphonic acid, carboxylic acids such as lauric acid, oleic acid or stearic acid, partially polymerized siloxanes (known as silicone oils), or mixtures thereof.

  The hydrophobic material may generally be added to the mixture to be separated, at least one surface modifying material, and at least one magnetic particle. In other embodiments, the hydrophobic material is added to at least one magnetic particle prior to addition to the mixture. Advantageously, in the case of silicon-based hydrophobic materials, in contact comprising a suitable precursor and water for a period of time, for example 1 second to 72 hours, prior to contact resulting in at least one magnetic particle. An intermediate step to generate the active agent in situ may be added.

  In one possible embodiment of step (B) of the process according to the invention, at least one magnetic particle is added to a mixture comprising the mixture to be separated in the dispersion. In another possible embodiment of step (B) of the process according to the invention, at least one magnetic particle is added to the mixture comprising the mixture to be separated without any dispersant. The first embodiment is preferred.

  In general, any dispersion medium that does not completely dissolve at least one magnetic particle when at least one magnetic particle is added in the dispersion may be used. Suitable dispersion media for dispersion are selected, for example, from the group consisting of water, water-soluble organic compounds and mixtures thereof, with water being particularly preferred. It is particularly preferred to disperse the mixture to be separated using the same dispersion medium used, preferably water.

  According to the present invention, the amount of dispersion medium for predispersing the magnetic particles may generally be selected to provide a slurry or dispersion that can be easily stirred and / or transported. In a preferred embodiment, the amount of the mixture to be treated is 10-60% by weight, based on the total slurry or dispersion.

  According to the invention, a dispersion of magnetic particles can be produced by methods known to those skilled in the art. In a preferred embodiment, the magnetic particles to be dispersed and the appropriate amount of dispersion medium or mixture of dispersion media are combined in a suitable reactor and are prepared by equipment known to those skilled in the art, for example by a mechanical propeller stirrer, for example Stirring is carried out at a temperature of ˜80 ° C., preferably at room temperature.

  In step (B), which may be combined with step (A) of the method according to the invention, the at least one magnetic particle becomes attached to at least one metal. The attachment of the magnetic particles to the at least one metal is, for example, when the at least one metal is associated with magnetic particles, such as iron oxide or any other ferromagnetic compound, or by magnetic interaction or hydrophobized magnetite and hydrophobization. Due to the hydrophobic interaction of at least one metal made or both.

  In general, there is no binding interaction between at least one magnetic particle and other components present in the slag except at least one metal so that these components do not adhere to each other. Accordingly, the additive composition of at least one metal and at least one magnetic particle is present with further other components in the mixture after step (B).

  Contact in step (B) of the method of the present invention may be brought about by methods generally known to those skilled in the art. Step (B) may be carried out in bulk or in dispersion, preferably in suspension, particularly preferably in aqueous suspension. In one embodiment of the method of the invention, step (B) is carried out in bulk, i.e. in the absence of a dispersion medium.

  For example, ground slag to be treated, at least one surface modifying material and / or at least one magnetic particle are combined and mixed in the proper amount without using any dispersion medium. Suitable mixing devices are generally known to the person skilled in the art, for example a mill, for example a ball mill. In this embodiment, step (B) may be performed on the same device as that used in step (A).

  In a further preferred embodiment, step (B) is carried out in dispersion, preferably in suspension. Suitable dispersion media are all dispersion media in which the mixture from step (B) is not completely dissolved. Suitable dispersion media for producing the slurry or dispersion according to step (B) of the present invention are selected from the group consisting of water, water-soluble organic compounds such as alcohols having 1 to 4 carbon atoms, and mixtures thereof. Preferably water.

  When step (B) of the process according to the invention is carried out in a dispersion, it is preferably 1 to 60% by weight, preferably 10 to 45% by weight, based on the total amount of solids to be dispersed respectively. Particularly preferably, a dispersion having a solids content of 30 to 40% by weight is used.

  Step (B) of the process according to the invention is generally carried out at a temperature of from 1 to 80 ° C., preferably from 20 to 40 ° C., particularly preferably at ambient temperature.

  The at least one surface modifying material is generally used in an amount that is sufficient to achieve the desired effect, and hydrophobizes at least one metal in the presence of other materials that are not desired, It produces a hydrophobic interaction between the hydrophobic magnetite. In a preferred embodiment, the at least one surface-modifying substance comprises 1000 g / t of slag to be separated from slag 5 g / t to be separated, particularly preferably 50 g / t of slag to be separated. It is added in an amount of 200 g / t of smelting slag to be separated from t, more preferably 180 g / t of smelting slag to be separated from 80 g / t of smelting slag to be separated.

  In general, the amount of at least one magnetic particle is determined by a person skilled in the art in such a way that the total amount of at least one first material can advantageously be separated by agglomeration with at least one magnetic particle. In a preferred embodiment of the process according to the invention, the at least one magnetic particle is 0.001 to 6% by weight, preferably 0.05 to 4.5% by weight, with respect to the slag to be separated in each case, It is particularly preferably added in an amount of 0.1 to 3% by weight.

  The invention therefore advantageously relates to the method described above, wherein at least one magnetic particle is added in an amount of 0.1 to 3% by weight, with respect to the slag to be separated.

  The obvious effect associated with this particular amount of at least one magnetic particle used advantageously is that the agglomerates obtained after step (D) of the method according to the invention are advantageously directly processed further, For example, it may be transferred to a smelting method.

  After step (A) or step (B) of the method according to the invention, a mixture comprising a further component of the slag and an aggregate of at least one metal and at least one magnetic particle is obtained, wherein at least one surface modification is obtained. The material is located at least partially between the at least one metal and the at least one magnetic particle, optionally in an aqueous dispersion.

Step (C):
Optional step (C) comprises adding at least one dispersant to the mixture obtained in step (A) or (B) to obtain a dispersion having a suitable concentration.

  In one embodiment, when step (A) and step (B) are performed in bulk, the mixture obtained after step (A) or (B) is a further component of slag, as well as at least one metal. And at least one particle or aggregate of magnetic particles, wherein in one embodiment, the at least one surface modifying material is located between the at least one metal and the at least one magnetic particle. In this case where steps (A) and (B) are carried out in bulk, step (C) of the method of the invention is advantageously carried out, ie at least one suitable dispersion medium is obtained in step (B). Is added to the resulting mixture to obtain a dispersion having a suitable concentration.

  In a second possible and preferred embodiment according to the invention, wherein steps (A) and / or (B) of the method of the invention are carried out in a dispersion, step (C) is not carried out. However, also in this embodiment, step (C) can be carried out, i.e. another dispersion medium is added to obtain a dispersion having a low concentration.

  Suitable dispersion media are all the dispersion media mentioned above with respect to steps (A) and (B). In one particularly preferred embodiment, the dispersion medium in steps (A) and (B) is water. A particularly preferred dispersion medium added in step (C) of the process according to the invention is water, optionally mixed with at least one polar organic solvent mentioned for step (A).

  Thus, step (C) converts the mixture present in bulk from steps (A) and (B) into a dispersion or is already present in the dispersion from steps (A) and / or (B). Converting the mixture to a low concentration dispersion by the addition of a dispersion medium.

  According to the present invention, the amount of dispersion medium added in steps (A) and / or (B) may generally be selected so as to obtain a dispersion that can be easily stirred and / or transported.

  In a preferred embodiment, the amount of dispersion medium added in step (C) of the process according to the invention is from 1 to 80% by weight, preferably from 10 to 45% by weight, based on the total amount of solids to be dispersed respectively. %, In particular to obtain a dispersion having a solids content of 30 to 40% by weight.

  The addition of the dispersion medium in step (C) of the present invention may be carried out according to the present invention by all methods known to those skilled in the art.

Step (D):
Step (D) of the method of the present invention comprises separating the particles from the mixture of step (A) or the aggregates from the mixture of step (B) or (C) by applying a magnetic field.

  In one embodiment of the method according to the invention, step (D) comprises separating the particles from the mixture of step (A) or (A1), respectively, by applying a magnetic field. In this embodiment, the slag to be treated includes at least one metal to be treated and a magnetic material, such as an iron-containing oxide. Said components are present in particular in the respective particles after step (A) or (A1).

  In a second embodiment of the method according to the invention, step (D) comprises separating the agglomerates from the mixture of step (B) or (C) by applying a magnetic field. In this embodiment, the crushed slag obtained after step (A) is further processed in step (B) according to the invention to obtain magnetic aggregates.

  In general, step (D) is carried out in any magnetic device suitable for separating magnetic particles from a dispersion, such as a drum separator, a high or low density time separator, a continuous belt type separator, etc. Good.

  Step (D) is performed in a suitable embodiment by introducing permanent magnets into the reactor in which the mixture of step (D) is present. In a preferred embodiment, a flow-conducting wall composed of non-magnetic material, for example a separator wall, is present between the permanent magnet and the mixture to be treated. In a preferred embodiment, step (D) is introduced at least partially in a reactor that is internally covered with permanent magnets. These permanent magnets may be adjusted mechanically. According to another embodiment, the addition of the mixture obtained in step (A), (A1), (B) or (C) is mechanically adjusted.

  In a preferred embodiment, the magnetic separation device makes it possible to wash the magnetic separation while separating with a dispersant, for example water. This washing advantageously removes inert materials from the magnetic mineral and leads to high quality valuables.

  In a preferred embodiment, step (D) is carried out continuously or semi-continuously, in which case the mixture to be treated advantageously flows through the separator in a dispersion. The flow rate of the dispersion to be treated is generally adjusted to obtain an advantageous yield of separated magnetic aggregates. In one preferred embodiment, the flow rate of the dispersion to be treated is between 10 mm / sec and 1000 mm / sec.

  The pH value of the dispersion treated by step (D) is generally neutral or weakly basic, and the pH value is about 6-8. In a preferred embodiment, it is not necessary to adjust the pH value of the dispersion obtained in step (A) or (B).

  Step (D) of the process according to the invention is carried out at any suitable temperature, for example 10-60 ° C., preferably at ambient temperature.

  In a continuous or semi-continuous process, the mixture is advantageously mixed by turbulence and is preferably not further stirred.

  The magnetic agglomerates can be separated from the apparatus in which the magnetic surface and / or magnetic separation is performed according to the invention by all methods known to those skilled in the art.

  In a preferred embodiment, the magnetic agglomerates are removed by flushing with a suitable dispersion medium. Suitable dispersion media are described above. In one preferred embodiment, water is used to wash away the separated magnetic aggregates.

  The separated magnetic aggregates may later be dehydrated and / or dried by methods known to those skilled in the art. The magnetic agglomerates are dehydrated until a suitable solids content, in particular water content, advantageously reaches less than 30% by weight.

  The method according to the invention comprises steps (A) to (D), whereby particles or agglomerates comprising at least one magnetic particle and at least one metal are obtained. In one particularly preferred embodiment, these particles or agglomerates are suitable for direct processing and obtain at least one metal in pure form.

The present invention further includes the following step (E) after step (D):
(E) Further relates to the process according to the invention, wherein the step of treating the particles or aggregates from step (D) is carried out by smelting, extraction and / or wet chemical purification.

  The magnetic particles or agglomerates obtained in step (D) advantageously comprise iron containing magnetic substances or magnetic particles in addition to at least one metal which is at least one noble metal. Particles or agglomerates obtained in step (D) of the process according to the invention, since iron is substantially necessary for the melting and / or smelting process to obtain at least one metal in pure form The product may be processed directly in the smelting and / or melting process.

  In the case where noble metals are used as the first material in combination with iron-containing magnetic particles, no further addition of other iron-containing compounds is required. Instead, magnetic iron oxide particles guided with noble metals are added to the furnace supplied instead of iron oxide, otherwise added to the process.

The present invention further includes the following step (F) after step (D):
(F) relates to a method according to the invention, wherein the agglomerates from step (D) are cleaved and, optionally, the step of treating at least one metal by smelting, extraction and / or wet chemical purification is carried out.

  Optional step (F) of the method according to the invention is advantageously when the aggregate is formed in step (B) by a hydrophobic interaction between at least one metal and at least one magnetic particle, be introduced. Therefore, these agglomerates need to be cleaved to obtain at least one metal that may be further processed by smelting, melting and / or refining.

  Aggregate cleavage is preferably carried out in a destructive or non-destructive manner, preferably in a non-destructive manner, i.e. in a way that the individual components present in the dispersion are not chemically converted. The

  The cleavage is advantageously carried out by all methods known to those skilled in the art that are suitable for cleaving additional products in such a way that at least one metal magnetic particle can be recovered in a reusable form. Good.

  In a preferred embodiment, the cleavage according to the present invention is a substance selected from the group consisting of organic solvents, basic compounds, acidic compounds, oxidizing agents, reducing agents, surface active compounds and mixtures thereof with additional products. Acted by processing. In one preferred embodiment, cleavage occurs by use of a biodegradable surfactant having a concentration in the critical micelle concentration range.

  Optional smelting, melting and / or refining is performed by step (F) and methods known to those skilled in the art. In a preferred embodiment, smelting, extraction and / or purification is carried out in step (F).

In particular, in a first embodiment (variant 1), the invention advantageously comprises at least the following steps:
(A) pulverizing slag to obtain particles,
(C) optionally adding at least one dispersant to the mixture obtained in (A) to obtain a dispersion having a suitable concentration, and (D) applying the magnetic field to the step (A) or ( C) The method according to the invention comprising the step of separating particles from the mixture.

  This preferred first embodiment of the process according to the invention comprising process step (A), optionally (C) and (D) is advantageously obtained by slow cooling and the slag formed under reducing conditions is separated. Introduced when it should be done.

In particular, in a second embodiment (variant 2), the invention advantageously comprises at least the following steps:
(A) pulverizing slag to obtain particles,
(A1) adding at least one dispersant to the mixture obtained in (A) to obtain a dispersion having a suitable concentration;
(B) The pulverized slag of step (A) and at least one magnetic particle are brought into contact with each other in the presence of at least one dispersant, and at least one metal and at least one magnetic particle are aggregated by magnetic interaction. A process leading to the formation of an object,
(D) relates to a method according to the invention comprising the step of separating the agglomerates from the mixture of step (B) or (C) by application of a magnetic field.

  This preferred second embodiment of the process according to the invention, comprising process steps (A), (A1), (B) and (D), is advantageously cooled rapidly (quenched) occurring under reducing conditions. This is introduced when the slag obtained by the slag is to be separated.

In particular, in the third embodiment (variant 3), the invention advantageously provides at least the following step (A) pulverizing slag to obtain particles,
(B) Optionally, the ground slag of step (A) is contacted with at least one magnetic particle and / or at least one surface modifying material, optionally in the presence of at least one dispersant, to provide magnetic and / or hydrophobic properties. Resulting in the formation of aggregates of at least one metal and at least one magnetic particle by sexual interaction;
(C) optionally adding at least one dispersant to the mixture obtained in step (A) or (B) to obtain a dispersion having a suitable concentration, and (D) the mixture of step (A). Or agglomerates from the mixture of steps (A), (B) or (C) are separated by application of a magnetic field.

  This preferred third embodiment of the process according to the invention comprising process steps (A), (B) optionally (C) and (D) is advantageously used for the rapid cooling (quenching) that takes place under reducing conditions. Introduced when the slag obtained by the treated slag is to be separated.

  The invention further relates to the use of at least one magnetic particle for the separation of slag, in particular for separation from at least one metal slag.

  In particular, the invention relates to the use according to the invention, wherein at least one magnetic particle comprises iron or iron oxide.

  General and preferred embodiments of the slag, the components present in the slag, the metal to be separated, and other conditions are described above with respect to the process according to the invention.

Examples PGM is an abbreviation for Au, Pt, Ir, Pd, Os, Ag, Hg, Rh, Ru, especially Au, Pt, Pd, Rh, more preferably Pt, Pd, Rh.

Example 1:
Example 1 is performed using magnetite that has already been hydrophobized, and a surface modifying material is added to hydrophobize at least one metal that is valuable, such as Pd, Pt and Rh.

27% by weight SiO ₂ , 26% by weight CaO, 34% by weight Al ₂ O ₃ , 4% by weight MgO, 3% by weight P ₂ O ₅ , 3% by weight ZrO ₂ , 2% by weight Fe ₂ O ₃ 300 g of electric furnace slag having a composition of 1 wt% CeO ₂ , less than 1 wt% Cr ₂ O ₃ , 17 ppm Pt, 12 ppm Pt and 2.5 ppm Rh in a ball mill for 60 minutes, Grind in the presence of 300 ml water and 500 g zirconia balls (1.7-2.2 mm size). The material is screened with a 100 μm sieve after grinding. Fine debris (particle size less than 100 μm) is treated with 100 g / t octylxanthan and with 2 g / 100 g hydrophobic magnetite (E 8707 H, Lanxess) for an additional 5 minutes. The slurry is mixed with water to a solids content of 20% by weight and pumped through a high strength filter and the magnetic compound is removed magnetically.

  After separation, 2.66 g of magnetic concentrate was prepared at concentrations of 630 ppm Pt, 520 ppm Pd and 95 ppm Rh, and the yields were Pt: 95.6%, Pd: 78.0%, Rh: < Calculated at 99%.

Example 2:
Example 2 is performed using non-hydrophobized magnetite to separate at least one metal that is valuable, such as Pd, Pt and Rh, without the addition of surface modifying materials.

27% by weight SiO ₂ , 26% by weight CaO, 34% by weight Al ₂ O ₃ , 4% by weight MgO, 3% by weight P ₂ O ₅ , 3% by weight ZrO ₂ , 2% by weight Fe ₂ O ₃ 100 g of electric furnace slag having a composition of 1 wt% CeO ₂ , less than 1 wt% Cr ₂ O ₃ , 17 ppm Pt, 12 ppm Pt and 2.5 ppm Rh in a ball mill for 60 minutes, Grind in the presence of 300 ml water and 500 g zirconia balls (1.7-2.2 mm size). The material is screened with a 100 μm sieve after grinding. Fine debris (particle size less than 100 μm) is treated with 1 g / 100 g of non-hydrophobic magnetite (E 8706, Lanxess). The slurry is mixed with water to a solids content of 20% by weight and the magnetic compound is removed magnetically.

  After separation, 1.67 g of magnetic concentrate was produced at a concentration of 303 ppm Pt, 394.5 ppm Pd and 76 ppm Rh, and the yields were Pt: 48.4%, Pd: 40.3%, Rh : Calculated at 48.4%.

Example 3:
The method according to Example 3 is carried out without the use of additional magnetite or additional surface modifying material.

27% by weight SiO ₂ , 26% by weight CaO, 34% by weight Al ₂ O ₃ , 4% by weight MgO, 3% by weight P ₂ O ₅ , 3% by weight ZrO ₂ , 2% by weight Fe ₂ O ₃ 100 g of electric furnace slag having a composition of 1 wt% CeO ₂ , less than 1 wt% Cr ₂ O ₃ , 17 ppm Pt, 12 ppm Pt and 2.5 ppm Rh in a ball mill for 60 minutes, Grind in the presence of 300 ml water and 500 g zirconia balls (1.7-2.2 mm size). The material is screened with a 100 μm sieve after grinding. The fine debris (particle size less than 100 μm) is mixed with water to a solids content of 20% by weight and the magnetic compound is removed magnetically.

  After separation, 1.67 g of magnetic concentrate was produced at a concentration of 1880 ppm Pt, 2270 ppm Pd and 390 ppm Rh, and the yield was calculated as Pt: 14%, Pd: 18%, Rh: 17%. .

Example 4:
The process according to Example 3 is carried out without using any additional magnetite or additional surface modification.

300g electric furnace slag is used. The electric furnace slag, containing 30-40% of SiO _2, 30-40% of Al ₂ O ₃ and / or other metal oxides. This slag contains less than 5% sulfide. This slag contains less than 5% sulfide. In addition, 1.1% Fe and 0.1% Ni are present and 22 ppm Pt, 22 ppm Pd, 5 ppm Rh and 0.15 ppm Au, Pt, Pd, Rh and Au are precious metals (PGM). ).

The slag is ground in a stirred ball mill to d ₈₀ = 130 μm and suspended in water (20% solids in water). The slurry is treated in particular with a magnetic separator capable of separating fine particles and very weak magnetic particles. After separation, 61-64% PGM can be recovered in the magnetic debris to the extent of 58 oz / t.

Example 5:
The process according to Example 3 is carried out without using any additional magnetite or additional surface modification.

300g electric furnace slag is used. The electric furnace slag, containing 30-40% of SiO _2, 30-40% of Al ₂ O ₃ and / or other metal oxides. This slag contains less than 5% sulfide. In addition, 1.1% Fe and 0.1% Ni are present and 22 ppm Pt, 22 ppm Pd, 5 ppm Rh and 0.15 ppm Au, Pt, Pd, Rh and Au are precious metals (PGM). ).

The slag is ground in a stirred ball mill to d ₈₀ = 9 μm and suspended in water (20% solids in water). The slurry is treated in particular with a magnetic separator capable of separating fine particles and very weak magnetic particles. After separation, 68-72% PGM can be recovered in the magnetic debris to the extent of 144 oz / t.

Example 6:
Example 6 is performed using hydrophobized magnetite and surface modifying material to separate at least one metal that is valuable, such as Pd, Pt and Rh.

300g electric furnace slag is used. The electric furnace slag, containing 30-40% of SiO _2, 30-40% of Al ₂ O ₃ and / or other metal oxides. This slag contains less than 5% sulfide. In addition, 1.1% Fe and 0.1% Ni are present and 22 ppm Pt, 22 ppm Pd, 5 ppm Rh and 0.15 ppm Au, Pt, Pd, Rh and Au are precious metals (PGM). ).

The slag is ground in a stirred ball mill to d ₈₀ = 9 μm and suspended in water (20% solids in water). Further, 0.5 g of hydrophobized magnetite is added for every 100 g of slag (E 8707, Lanxess), and 100 g / t of amylxanthan (99%, Aldrich) is added. Sufficient shear energy is introduced to combine the particles including the hydrophobic magnetite and the surface modifying material and PGM. The slurry is then processed in particular with a magnetic separator capable of separating fine particles and very weak magnetic particles. After separation, 77-82% PGM can be recovered in the magnetic debris to the extent of 60 oz / t.

Example 7: Pure magnetic separation of slag with quench slag (steps A + C + D of the process according to the invention)
Slag is 28% SiO ₂ , 26% CaO, 35% Al ₂ O ₃ , 4% MgO, 3% P ₂ O ₅ , 3% ZrO ₂ , 2% Fe ₂ O ₃ (or Other Fe—O species such as Fe ₃ O ₄ ) have a composition of 1% CeO ₂ , 12 ppm Pt, 17 ppm Pd, 2.5 ppm Rh. The slag is quenched and this means that the hot slag is introduced into a concrete container with water. 300 g of this material is ground in a ball mill in the presence of 300 ml of water and 500 g of zirconia balls (size of 1.7-2.2 mm). The material is screened with a 100 μm sieve after grinding. Fine debris (d ₈₀ = 9 μm), step A (step of grinding as already described), C (step of adding dispersant, in this case water to a solids content of 15% by weight), and D Process according to the embodiment of the method described only in (magnetic separation step).

  36% Pt, 56% Pd and 12% Rh are magnetically recovered to a total extent of 1577 ppm PGM.

Example 8: Auxiliary magnetic separation of slag with quenched slag (step A + A1 + BC + D of the method according to the invention)
Slag is 28% SiO ₂ , 26% CaO, 35% Al ₂ O ₃ , 4% MgO, 3% P ₂ O ₅ , 3% ZrO ₂ , 2% Fe ₂ O ₃ (or Other Fe—O species such as Fe ₃ O ₄ ) have a composition of 1% CeO ₂ , 12 ppm Pt, 17 ppm Pd, 2.5 ppm Rh.

  The slag is quenched and this means that the hot slag is introduced into a concrete container with water.

300 g of this material is ground in a ball mill in the presence of 300 ml of water and 500 g of zirconia balls (size of 1.7-2.2 mm). The material is screened with a 100 μm sieve after grinding. Fine debris (d ₈₀ = 9 μm), step A (step of grinding as already described), A1 (step of adding dispersant, in this case water to a solids content of 15% by weight), step B (Process of adding magnetite not surface modified, in this case adding 3 g / 100 g E 8706 (Lanxess)), and processing according to the embodiment of the method described only in D (magnetic separation step). Other possibilities to ensure the addition of unsurface-modified magnetite in a mill (stirred ball mill, ball mill, verti mill, etc.) or in a t-tube or good mixing and some shear input Can be done with any device.

  44% Pt, 63% Pd and 69% Rh are magnetically recovered to a total extent of 330 ppm PGM. Magnetite that is not surface modified is not removed from the concentrate containing PGM, resulting in a reduction in quality.

Example 9: Auxiliary magnetic separation of slag with quench slag (step A + A1 + B + D of the method according to the invention)
Slag is 28% SiO ₂ , 26% CaO, 35% Al ₂ O ₃ , 4% MgO, 3% P ₂ O ₅ , 3% ZrO ₂ , 2% Fe ₂ O ₃ (or Other Fe—O species such as Fe ₃ O ₄ ) have a composition of 1% CeO ₂ , 12 ppm Pt, 17 ppm Pd, 2.5 ppm Rh.

  The slag is quenched and this means that the hot slag is introduced into a concrete container with water.

300 g of this material is ground in a ball mill in the presence of 300 ml of water and 500 g of zirconia balls (size of 1.7-2.2 mm). The material is screened with a 100 μm sieve after grinding. Fine debris (d ₈₀ = 9 μm), step A (step of grinding as already described), A1 (step of adding dispersant, in this case water to a solids content of 15% by weight), step B (Other oxides where wood products are not desired, in this case 650 g / t C ₈ -xanthate (BASF R & D sample) and hydrophobic magnetite (E 8707H, magnetite hydrophobized with silicone oil, Lanxess), 100 g It is processed according to the embodiment of the method described only in the step of adding a scavenger that selectively hydrophobizes valuables in the presence of 3 g of hydrophobic magnetite per slag) and D (magnetic separation step). Addition of scavenger and hydrophobic magnetite in the mill (stir ball mill, ball mill, verti mill, etc.) or in t-tube or other possibilities to ensure good mixing and some shear input Can be done with any device. For optimal dispersion of hydrophobic magnetite, 0.01% Lutensol XL 80 was added as a surfactant.

  83% Pt, 88% Pd and 88% Rh are magnetically recovered to a total extent of 1362 ppm PGM. Magnetite is not removed from the concentrate containing PGM, resulting in a loss of quality. However, the quality can be improved by washing the magnetite by washing away after the magnetic separation step.

Example 10: Magnetic separation of slag with slowly cooled slag (steps A + C + D of the method according to the invention)
Slag is 28% SiO ₂ , 26% CaO, 35% Al ₂ O ₃ , 4% MgO, 3% P ₂ O ₅ , 3% ZrO ₂ , 2% Fe ₂ O ₃ (or Other Fe—O species such as Fe ₃ O ₄ ) have a composition of 1% CeO ₂ , 12 ppm Pt, 17 ppm Pd, 2.5 ppm Rh.

  The slag was allowed to cool slowly to RT by exposing the slag to RT for several days.

300 g of this material is ground in a ball mill in the presence of 300 ml of water and 500 g of zirconia balls (10 mm size). The material is screened with a 100 μm sieve after grinding. Fine debris (d ₈₀ = 9 μm), step A (step of grinding as already described), C (step of adding dispersant, in this case water to a solids content of 15% by weight), and D Process according to the embodiment of the method described only in (magnetic separation step). 78% Pt, 77% Pd and 79% Rh are magnetically recovered to a total extent of 2333 ppm PGM.

Example 11: Auxiliary magnetic separation of slag with slowly cooled slag (step A + A1 + B + D of the method according to the invention)
300 g of this material is ground in a ball mill in the presence of 300 ml of water and 500 g of zirconia balls (size of 1.7-2.2 mm). The material is screened with a 100 μm sieve after grinding. Fine debris (d ₈₀ = 9 μm), step A (step of grinding as already described), A1 (step of adding dispersant, in this case water to a solids content of 15% by weight), step B (Other oxides for which wood products are not desired, in this case 100 g / t of C ₈ -xanthate (BASF R & D sample) and hydrophobic magnetite (E 8707H, magnetite hydrophobized with silicone oil, Lanxess), 100 g It is processed according to the method embodiment described only in the step of adding a scavenger that selectively hydrophobizes the valuables in the presence of 1 g of hydrophobic magnetite per slag) and D (magnetic separation step). Addition of scavenger and hydrophobic magnetite in the mill (stir ball mill, ball mill, verti mill, etc.) or in t-tube or other possibilities to ensure good mixing and some shear input Can be done with any device. For optimal dispersion of hydrophobic magnetite, 0.01% Lutensol XL 80 was added as a surfactant.

  83% Pt, 83% Pd and 86% Rh are magnetically recovered to a total extent of 1506 ppm PGM. Magnetite is not removed from the concentrate containing PGM, resulting in a loss of quality. However, the quality can be improved by washing the magnetite by washing away after the magnetic separation step.

Claims (12)

At least the following steps:
(A) pulverizing slag to obtain particles,
(B) Optionally, the ground slag of step (A) is contacted with at least one magnetic particle and / or at least one surface modifying material, optionally in the presence of at least one dispersant, to provide magnetic and / or hydrophobic properties. Resulting in the formation of aggregates of at least one metal and at least one magnetic particle by sexual interaction;
(C) optionally adding at least one dispersant to the mixture obtained in step (A) or (B) to obtain a dispersion having a suitable concentration, and (D) by applying a magnetic field, Separating at least one metal from a slag comprising at least one metal and other components, comprising separating particles from the mixture of (A) or agglomerates from the mixture of step (B) or (C). Method. After the step (D), the next step (E):
(E) The method according to claim 1, further comprising the step of treating the particles or aggregates from step (D) by smelting, extraction and / or wet chemical purification. After the step (D), the next step (F):
The method of claim 1, wherein (F) cleaving the agglomerates from step (D) and optionally treating at least one metal by smelting, extraction and / or wet chemical purification.   The at least one metal is Ag, Au, Pt, Pd, Rh, Ru, Ir, Os, Cu, Mo, Ni, Mn, Zn, Pb, Te, Sn, Hg, Re, V, Fe, and mixtures thereof. 4. The method according to any one of claims 1 to 3, wherein the method is selected from the group consisting of:   The method according to any one of claims 1 to 4, wherein the slag introduced during the step (A) is an artificially produced slag. The _{slag, SiO 2, CaO, Al 2} O 3, MgO, P 2 O 3, ZrO 2, Fe 2 O 3, Fe 3 O 4, CeO 2, Cr 2 O 3, those complex oxide matrix and mixtures 6. A method according to any one of claims 1 to 5, comprising at least one compound selected from the group consisting of.   When carrying out said step (B), at least one magnetic particle is added in step (B) in an amount of 0.1 to 3% by weight with respect to the slag to be separated. The method according to any one of the above.   8. A method according to any one of the preceding claims, wherein the at least one metal is present in the slag in an amount of 0.01 to 1000 g / t of slag to be separated.   9. A method according to any one of claims 1 to 8, wherein the at least one magnetic particle is an iron-containing compound. After step (A), (A1) carrying out step (A1) including the step of adding at least one dispersant to the mixture obtained in step (A) to obtain a dispersion having a suitable concentration. 10. The method according to any one of claims 1 to 9.   Use of at least one magnetic particle for slag separation.   12. Use according to claim 11, wherein the at least one magnetic particle comprises iron or iron oxide.