WO2014044527A1 - Procédé permettant d'obtenir au moins un chlorure de métal des terres rares et un métal des terres rares - Google Patents

Procédé permettant d'obtenir au moins un chlorure de métal des terres rares et un métal des terres rares Download PDF

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Publication number
WO2014044527A1
WO2014044527A1 PCT/EP2013/068258 EP2013068258W WO2014044527A1 WO 2014044527 A1 WO2014044527 A1 WO 2014044527A1 EP 2013068258 W EP2013068258 W EP 2013068258W WO 2014044527 A1 WO2014044527 A1 WO 2014044527A1
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WO
WIPO (PCT)
Prior art keywords
rare earth
earth metal
solution
extract solution
metal chloride
Prior art date
Application number
PCT/EP2013/068258
Other languages
German (de)
English (en)
Inventor
Elvira María FERNÁNDEZ SANCHIS
Karl Bernhard FRIEDRICH
Marc Hanebuth
Hanno Vogel
Daniel VOSSENKAUL
Original Assignee
Siemens Aktiengesellschaft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO2014044527A1 publication Critical patent/WO2014044527A1/fr

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B59/00—Obtaining rare earth metals
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F17/00—Compounds of rare earth metals
    • C01F17/10—Preparation or treatment, e.g. separation or purification
    • C01F17/17—Preparation or treatment, e.g. separation or purification involving a liquid-liquid extraction
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F17/00—Compounds of rare earth metals
    • C01F17/20—Compounds containing only rare earth metals as the metal element
    • C01F17/206—Compounds containing only rare earth metals as the metal element oxide or hydroxide being the only anion
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F17/00—Compounds of rare earth metals
    • C01F17/20—Compounds containing only rare earth metals as the metal element
    • C01F17/253—Halides
    • C01F17/271—Chlorides

Definitions

  • the invention relates to processes for obtaining at least one rare earth metal chloride and for obtaining a rare earth metal from a base material containing at least one rare earth metal compound.
  • the basic material used here are ores or clay minerals which contain soluble and / or insoluble rare earth metal compounds, as well as other recyclable materials which contain rare earth metals, such as Nd-Fe-B magnets and the like.
  • ionic adsorption stones are used as clay minerals.
  • WO 2011/091231 A1 discloses a processing of ore minerals, wherein inter alia a transfer of rare earth elements into an aqueous solution is described.
  • the base material is crushed and concentrated enriched with the rare earth metal phase.
  • Rare earth elements usually do not occur singly in ores or clay minerals, but are found in association with a plurality of other rare earth elements which are to be found adjacent in the periodic table of the chemical elements.
  • the concentrate is now chemically digested, with insoluble rare earth metal compounds, usually in the form of carbonates or phosphates, are converted into soluble rare earth metal compounds.
  • concentrated acids or bases such as sulfuric acid H 2 S0 4 or sodium hydroxide NaOH, are used in a high-temperature process. This is followed by a transfer of the soluble rare earth metal compounds in an aqueous phase.
  • crushed recycled material containing rare earth metals can be rare earth metal compounds chemically dissolve.
  • an aqueous base solution containing the dissolved rare earth metal compound (s) and, if appropriate, further soluble compounds, which may comprise unwanted heavy metals, for example, is formed.
  • the unwanted heavy metal compounds can largely be precipitated and separated.
  • the actual separation of the basic solution, in which the individual rare earth elements are selectively separated as precisely as possible, is usually carried out by means of a liquid-liquid extraction.
  • a suitable extractant By means of a suitable extractant, the rare earth metal ions dissolved in the aqueous base solution are converted into an electrically neutral species which accumulate in an organic phase.
  • rare earth metal ions can be selectively enriched in the organic phase and separated off in succession. That's the way to go also chemically closely related rare earth elements separate from each other.
  • Typical cationic extractants used here are di-2-ethylhexyl phosphoric diesters (abbreviation: P204), or 2-ethylhexyl phosphonic acid (2-ethylhexyl) esters (abbreviated to P507). Due to its nonpolar properties, such an extractant is predominantly in the form of dimers in the organic phase.
  • the extraction process is based on the fact that hydrogen atoms deprotonate the extractant, whereby the charge resulting from the cleavage of the protons is compensated by the formation of electrically neutral value metal complexes, in particular rare earth metal complexes. The rare earth metal complexes accumulate in the organic phase.
  • an extraction step is usually not sufficient to achieve sufficient separation of the elements. Therefore, it is customary to use a multistage extraction unit comprising one or more extraction columns or cascades of extraction stages, wherein typically a total of 100 to 500 extraction stages are used.
  • the rare earth metal elements transferred and separated into the organic phase are then separated again from the organic phase by a so-called "stripping.”
  • acid is usually added thereto and the extractant is regenerated at the same time and may be reused
  • There remains one or more aqueous extract solutions each containing substantially a single rare earth metal element or a mixed concentrate containing a plurality of rare earth metal elements, particularly in the form of rare earth chloride.
  • the contained rare earth metal element is precipitated in succession as sparingly soluble rare earth metal carbonate or oxalate, separated off, dried and converted at high temperatures into a rare earth metal oxide or calcined.
  • the rare earth metal oxide is now usually reduced in a complicated process, either by reduction with a less noble element or by fused-salt electrolysis. After a direct reduction of the rare earth oxides is difficult, they are usually first converted back into rare earth metal chlorides or fluorides, which are then reduced to the rare earth metals.
  • the object is achieved for the process for obtaining at least one rare earth metal chloride from a base material comprising at least one rare earth metal compound comprising the following steps:
  • Extract solution is separated from the base solution comprising the at least one soluble rare earth metal compound in the form of at least one rare earth metal chloride;
  • the object is achieved for the method for obtaining at least one rare earth metal from a base material containing at least one rare earth metal compound, comprising the following steps:
  • Extract solution is separated from the base solution having the at least one soluble rare earth metal compound in the form of at least one rare earth metal chloride;
  • the extraction can be carried out in both methods as a liquid-liquid extraction or by ion exchange as a liquid-solid extraction.
  • the residual base solution remaining after the extraction has been carried out may contain further rare earth metal chloride, so that the base residual solution can be subjected independently to step c) or steps c) and d).
  • the processes have the advantage of being able to save considerable amounts of chemicals which are saved for the conventional formation of rare earth metal oxide, which is subsequently reduced to rare earth metal.
  • the complexity of the processes is lower, allowing for a fast and efficient recovery of rare earth metal or rare earth metal chloride.
  • step c) it is preferred to first form a wet rare earth metal chloride which is dried in a neutral or reducing atmosphere to form the dry rare earth metal chloride.
  • a gas purging in particular with an inert gas or a reducing gas, such as HCl gas, accelerates the dehumidification and counteracts an undesirable formation of oxychlorides.
  • the extract solution is successively preferably subjected to predrying, distillative drying and filtration in step c) to form the wet rare earth metal chloride. This contributes to an optimization of the separation process in terms of time and costs.
  • the pre-drying of the extract solution to a pre-dried extract solution is carried out in particular with separation of a first part of the process water by means of electrodialysis and / or nanofiltration and / or reverse osmosis and / or evaporation due to heating.
  • the distillative drying of the predried extract solution originating from the predrying to a distillatively predried extract solution is carried out with separation of a second process water portion, wherein the temperature of the predried extract solution is increased to a boiling temperature of the predried extract solution.
  • a pre-dried extract solution boils under normal pressure at a temperature in the range of about 120 to 130 ° C.
  • the energy required to heat the predried extract solution to boiling temperature is preferably provided by waste heat from other process steps or regenerative energy sources.
  • the distillative drying coming from the distillative pre-dried extract solution is preferably cooled with precipitation of the rare earth metal chloride to an extract suspension.
  • the extract suspension is cooled to ambient temperature.
  • a heat exchanger device can be used in order to be able to continue to use the waste heat. Filtration, in particular, the cooled
  • Extract suspension is filtered, carried out by means of a segregator unit, in particular in the form of a filter press or a centrifuge, wherein the moist rare earth metal chloride and a third process water part are formed.
  • the third process water part contains usually still solved
  • Rare earth metal chloride is preferably partially fed back into the process.
  • the third process water part is partially recycled and mixed with further extract solution or alternatively with already predried extract solution.
  • Extract solution and / or pre-dried extract solution is in follow in the process water and the wet rare earth metal chloride separately.
  • the third process water part is not completely recycled to avoid contaminants in the third process water part
  • the first process water part and / or the second process water part are used again elsewhere in the process, preferably for the formation of hydrochloric acid.
  • the hydrochloric acid formed is used in particular in step a) for transferring the rare earth metal compound in solution and / or used in step b) in the extraction.
  • the hydrochloric acid is formed from the purge gas for drying the humid rare earth metal chloride in the form of HCl gas and the first and / or second process water part.
  • Figures 1 to 3 are intended to exemplify the methods of the invention for the recovery of rare earth and rare earth metal chloride. As shown: a process for the extraction of rare earth metal; a process for obtaining rare earth metal chloride; and
  • FIG. 1 shows a method for obtaining at least one rare earth metal 150 from a base material 100 containing at least one rare earth metal compound.
  • the base material 100 is usually crushed and in terms of
  • a concentrated acid such as hydrochloric acid or sulfuric acid 110
  • the rare earth metal compound converted into a soluble rare earth metal compound.
  • the pulp or the heap is heated at the same time.
  • an aqueous base solution 130 containing the soluble rare earth metal compound and optionally further soluble
  • the base solution 130 is collected in a collecting vessel 30, which may also be formed by a tube only, and fed into an extraction unit 40 comprising one or more extraction columns or cascades of extraction stages in which a liquid-liquid extraction takes place.
  • the extraction unit 40 here comprises a plurality of extraction reactors 41, 42, wherein a cationic extraction agent 50 is added to the base solution 130 in a first extraction reactor 41 of the extraction unit 40.
  • An aqueous extract solution 1 based on the soluble rare earth metal compound is separated from the base solution 130.
  • the residual base solution 60 is transferred to a second extraction reactor 42 of the extraction unit 40 and another extractant 51 is added.
  • a further aqueous extract solution 1 "based on a further soluble rare earth metal compound in the form of another rare earth metal chloride is separated off from the residual base solution 60. If appropriate, further soluble extractive metal compounds contained in the further residual base solution 61 are removed via further subsequent extraction reactors.
  • the extract solution 1 is transferred to a separation unit 70, in which a separation of the extract solution 1 in process water 140 and dry rare earth metal chloride 15 takes place.
  • a separation unit 70 preferably moist rare earth metal chloride 11 (cf. FIG. 2) is first formed, which is dried here as a purge gas 13 while supplying HCl gas.
  • Moist purging gas 14 is removed from the separation unit 70.
  • the dry rare earth metal chloride 15 is reduced to the rare earth metal 150 in a reduction unit 80.
  • FIG 2 shows a process for recovering rare earth metal chloride 15 to which a rare earth metal 150 recovery process of the present invention may also be based.
  • the separation unit 70 comprises a predrying unit 2 for receiving the extract solution 1, which is designed, for example, as a nanofiltration system.
  • a first process water part 3 is separated from the extract solution 1 and there remains a pre-dried extract solution 4, which is fed to a distillation unit 5 for distillative drying.
  • the distillation unit 5 By means of the distillation unit 5, the predried extract solution 4 is boiled and a second process water part 6
  • the first process water part 3 and second process water part 6 can be reused as process water 140 elsewhere in the process.
  • the distillatively predried extract solution 7 formed is cooled to ambient temperature, which takes place here in a heat exchanger unit 8.
  • the recovered thermal energy 81 can be used elsewhere in the process.
  • the rare earth metal chloride precipitates out as a solid and an extract suspension 10 is formed which subsequently in a separation unit 17 into the moist rare earth metal chloride 11 and a third process water part 9 is separated.
  • the third process water part 9 usually still contains dissolved rare earth metal chloride, so that this is preferably partially recycled and mixed with extract solution 1 and / or predried extract solution 4, the separation unit 70 passes through again.
  • the obtained moist rare earth metal chloride 11 is then dried in a drying unit 12 at a temperature in the range of 80 to 400 ° C with gas purging with HCl gas as the purge gas and a reduced pressure, in particular in the range of 20 to 80 kPa (absolute). Particularly advantageous in this case is a slow increase in the drying temperature over the drying time. In this case, preferably a higher pressure for the drying is selected at a low drying end temperature, and a lower pressure for the drying is selected at a high drying end temperature. During drying, residual moisture and water of crystallization are expelled.
  • the resulting dry rare earth metal chloride 15 is packed airtight and can be reduced by means of a reduction unit 80 directly to rare earth metal 150 (see FIG. 1).
  • FIG. 3 shows another method for obtaining rare earth metal chloride 15, to which a rare earth metal 150 recovery method according to the invention can likewise build up.
  • the same reference numerals as in FIG. 2 designate the same elements.
  • the predrying unit 2 is formed here by a heated evaporation plant. Furthermore, here the first process water part 3 and the second process water part 6 are brought together with the moist purge gas 14 and from it hydrochloric acid 16 is formed. The resulting excess additional thermal energy 91 is dissipated via a further heat exchanger unit 90. The from the cooling of the
  • Extract suspension 10 in heat exchanger unit 8 recovered thermal energy 81 and the further thermal energy 91 are used here for heating the predrying unit 2 and / or the distillation unit 5.
  • the cooled hydrochloric acid 16 is - depending on the need for dissolving chemicals, in this case hydrochloric acid 110 - supplied to the dissolving reactor 20 and / or used for the extraction in the extraction unit 40.
  • separation unit 70 may include other than the illustrated units to separate an extract solution into process water and dry rare earth metal chloride.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Analytical Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

L'invention concerne un procédé permettant d'obtenir au moins un chlorure de métal des terres rares à partir d'un matériau de base (100) contenant au moins un composé de métal des terres rares. Ce procédé comprend les étapes suivantes : a) mise en solution du ou des composés de métal des terres rares, une solution de base aqueuse (130) contenant au moins un composé de métal des terres rares soluble et éventuellement d'autres composés solubles étant formés; b) la mise en œuvre d'une extraction, une solution d'extrait aqueuse (1, 1') étant séparée de la solution de base (130), laquelle contient le ou les composés de métal des terres rares solubles sous forme d'au moins un chlorure de métal des terres rares; et c) la séparation de la solution d'extrait (1, 1') en eau de traitement (3, 6, 9, 140) et en chlorure de métal des terres rares sec (15). L'invention concerne en outre un procédé permettant d'obtenir un métal des terres rares.
PCT/EP2013/068258 2012-09-18 2013-09-04 Procédé permettant d'obtenir au moins un chlorure de métal des terres rares et un métal des terres rares WO2014044527A1 (fr)

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DE102012216647.5 2012-09-18
DE102012216647.5A DE102012216647A1 (de) 2012-09-18 2012-09-18 Verfahren zur Gewinnung mindestens eines Seltenerdmetallchlorids sowie eines Seltenerdmetalls

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WO2014044527A1 true WO2014044527A1 (fr) 2014-03-27

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Cited By (3)

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Publication number Priority date Publication date Assignee Title
CN103979727A (zh) * 2014-05-20 2014-08-13 赛普（无锡）膜科技发展有限公司 从硫酸稀土生产废水中回收水和硫酸盐类物质的方法
CN108910928A (zh) * 2018-09-18 2018-11-30 新特能源股份有限公司 两种金属氯化物的联产方法及两种金属氯化物
CN110776128A (zh) * 2018-07-31 2020-02-11 中铝稀土（江苏）有限公司 一种稀土废水的处理回收工艺

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CN111214958B (zh) * 2020-01-17 2022-07-19 中山大学 提取土壤稀土纳米颗粒的方法
CN114150167A (zh) * 2020-09-08 2022-03-08 中国科学院过程工程研究所 一种膜过程强化的无皂化稀土萃取分离新技术
CN113263042B (zh) * 2021-05-17 2023-09-29 赣州齐飞新材料有限公司 一种对稀土酸法废渣中稀土的回收装置

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Publication number Priority date Publication date Assignee Title
CN103979727A (zh) * 2014-05-20 2014-08-13 赛普（无锡）膜科技发展有限公司 从硫酸稀土生产废水中回收水和硫酸盐类物质的方法
CN110776128A (zh) * 2018-07-31 2020-02-11 中铝稀土（江苏）有限公司 一种稀土废水的处理回收工艺
CN110776128B (zh) * 2018-07-31 2022-06-21 盛和资源(江苏)稀土有限公司 一种稀土废水的处理回收工艺
CN108910928A (zh) * 2018-09-18 2018-11-30 新特能源股份有限公司 两种金属氯化物的联产方法及两种金属氯化物

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