KR101690819B1 - Method for extracting rare earth elements from phosphogypsum - Google Patents
Method for extracting rare earth elements from phosphogypsum Download PDFInfo
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- KR101690819B1 KR101690819B1 KR1020127003983A KR20127003983A KR101690819B1 KR 101690819 B1 KR101690819 B1 KR 101690819B1 KR 1020127003983 A KR1020127003983 A KR 1020127003983A KR 20127003983 A KR20127003983 A KR 20127003983A KR 101690819 B1 KR101690819 B1 KR 101690819B1
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- rare earth
- gypsum
- earth element
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- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 61
- 238000000034 method Methods 0.000 title claims abstract description 34
- PASHVRUKOFIRIK-UHFFFAOYSA-L calcium sulfate dihydrate Chemical compound O.O.[Ca+2].[O-]S([O-])(=O)=O PASHVRUKOFIRIK-UHFFFAOYSA-L 0.000 title description 2
- 239000010440 gypsum Substances 0.000 claims abstract description 39
- 229910052602 gypsum Inorganic materials 0.000 claims abstract description 39
- 238000000605 extraction Methods 0.000 claims abstract description 38
- 229910019142 PO4 Inorganic materials 0.000 claims abstract description 18
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims abstract description 18
- 239000010452 phosphate Substances 0.000 claims abstract description 18
- 239000000203 mixture Substances 0.000 claims abstract description 17
- 239000002253 acid Substances 0.000 claims abstract description 14
- 238000005341 cation exchange Methods 0.000 claims abstract description 12
- 239000000725 suspension Substances 0.000 claims abstract description 12
- 230000002378 acidificating effect Effects 0.000 claims abstract description 8
- ZODDGFAZWTZOSI-UHFFFAOYSA-N nitric acid;sulfuric acid Chemical compound O[N+]([O-])=O.OS(O)(=O)=O ZODDGFAZWTZOSI-UHFFFAOYSA-N 0.000 claims abstract description 7
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 44
- 239000000243 solution Substances 0.000 claims description 32
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 9
- 229910017604 nitric acid Inorganic materials 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 7
- 238000002156 mixing Methods 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 239000002699 waste material Substances 0.000 claims description 4
- 239000000020 Nitrocellulose Substances 0.000 claims description 3
- FJWGYAHXMCUOOM-QHOUIDNNSA-N [(2s,3r,4s,5r,6r)-2-[(2r,3r,4s,5r,6s)-4,5-dinitrooxy-2-(nitrooxymethyl)-6-[(2r,3r,4s,5r,6s)-4,5,6-trinitrooxy-2-(nitrooxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3,5-dinitrooxy-6-(nitrooxymethyl)oxan-4-yl] nitrate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O)O[C@H]1[C@@H]([C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@@H](CO[N+]([O-])=O)O1)O[N+]([O-])=O)CO[N+](=O)[O-])[C@@H]1[C@@H](CO[N+]([O-])=O)O[C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O FJWGYAHXMCUOOM-QHOUIDNNSA-N 0.000 claims description 3
- 229920001220 nitrocellulos Polymers 0.000 claims description 3
- 229940079938 nitrocellulose Drugs 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 239000003929 acidic solution Substances 0.000 claims 1
- 238000010298 pulverizing process Methods 0.000 claims 1
- 238000011084 recovery Methods 0.000 abstract description 17
- 230000008569 process Effects 0.000 abstract description 16
- 238000000926 separation method Methods 0.000 abstract description 10
- 239000003153 chemical reaction reagent Substances 0.000 abstract description 6
- 239000011507 gypsum plaster Substances 0.000 abstract 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 7
- 239000012141 concentrate Substances 0.000 description 7
- 238000012545 processing Methods 0.000 description 7
- 229910052586 apatite Inorganic materials 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 5
- 238000002425 crystallisation Methods 0.000 description 5
- 230000008025 crystallization Effects 0.000 description 5
- VSIIXMUUUJUKCM-UHFFFAOYSA-D pentacalcium;fluoride;triphosphate Chemical compound [F-].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O VSIIXMUUUJUKCM-UHFFFAOYSA-D 0.000 description 5
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 229910052698 phosphorus Inorganic materials 0.000 description 4
- 239000011574 phosphorus Substances 0.000 description 4
- 150000002910 rare earth metals Chemical class 0.000 description 4
- 239000011734 sodium Substances 0.000 description 4
- 229910052708 sodium Inorganic materials 0.000 description 4
- 150000007513 acids Chemical class 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000011591 potassium Substances 0.000 description 3
- 229910052700 potassium Inorganic materials 0.000 description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- -1 phosphorus compound Chemical class 0.000 description 2
- 150000003018 phosphorus compounds Chemical class 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000012445 acidic reagent Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000000559 atomic spectroscopy Methods 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009616 inductively coupled plasma Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 229910052747 lanthanoid Inorganic materials 0.000 description 1
- 150000002602 lanthanoids Chemical class 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000011505 plaster Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000000375 suspending agent Substances 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 150000003609 titanium compounds Chemical class 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000002604 ultrasonography Methods 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
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
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
- C22B3/065—Nitric acids or salts thereof
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
- C22B3/42—Treatment or purification of solutions, e.g. obtained by leaching by ion-exchange extraction
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Abstract
본 발명은 특히 인산석고로부터 희토류 원소를 회수하는 방법에 관한 것이다.
특허청구된 방법은 3.2 내지 1.2 비율로 1 내지 3 중량%의 농도를 갖는 황산-질산 혼합물 용액을 4 내지 5의 액체-고체 비율로 8 내지 12분 이내로 동시에 혼합되는 추출 현탁제 상에 유체 음파 작용과 함께 사용하여 인산석고로부터 희토류 원소를 산성 추출하고, 이어서 추출 현탁제로부터 불용성 석고를 분리하고 양이온-교환 필터를 통해 통과하게 함으로써 추출 용액으로부터 희토류 원소를 회수하는 것을 포함한다.
특허청구된 방법은 희토류 원소의 회수율을 증가시키고 공정의 시간을 반으로 줄여주어 더 낮은 농도의 시약 및 더 적은 부피의 산성 시약으로 달성되게 한다.The present invention relates in particular to a method for recovering rare earth elements from gypsum plaster.
The claimed process is characterized in that a sulfuric acid-nitric acid mixture solution having a concentration of 1 to 3% by weight in a ratio of 3.2 to 1.2 is applied to the extraction suspension simultaneously mixed within 8 to 12 minutes at a liquid- To acidic extraction of the rare earth element from the phosphate gypsum, followed by separation of the insoluble gypsum from the extraction suspension and through a cation-exchange filter to recover the rare earth element from the extraction solution.
The claimed process increases the recovery of rare earth elements and reduces the time of the process in half, resulting in lower concentrations of reagents and less volume of acid reagents.
Description
본 발명은 인산석고로부터 희토류 원소, 특히 희토류 원소의 화학적 화합물을 회수하는 방법에 관한 것이다.The present invention relates to a method for recovering a rare earth element, especially a rare earth element, from a chemical compound of gypsum.
오늘날 희토류 산업에서 비용의 60% 초과는 광석 채굴 및 가공과 관련이 있다. 그러므로, 희토류 원소가 부표면 광물원으로부터 채굴되는 소수(minor) 성분인 테크노제닉(technogenic) 1급 생성물을 사용하는 것이 수익성이 있다. 인회석 인산석고는 그러한 목적에 대해 1급 생성물로서 사용될 수 있다. 인산석고는 무기 비료 제조를 위한 인회석 농축물의 황산 공정 동안 생성된다. 인산석고는 CaSO4 X 2H2O로 구성된 천연 석고석과는 반대로 테크노제닉 기원의 생성물이다. 이것이 후자가 희토류 및 다른 원소의 화합물인 상당한 양의 불순물(8 내지 19%)을 가지는 이유이다. 희토류 원소의 함량은 인회석 농축물의 조성에 따라 0.5 내지 1.1% 이내이다. Today, over 60% of the costs in the rare earth industry are related to ore mining and processing. Therefore, it is profitable to use a technogenic first-class product, a minor component of rare earth elements mined from a minor surface mineral source. Apatite phosphate gypsum can be used as a first-class product for such purpose. Phosphate gypsum is produced during the sulfuric acid process of apatite concentrate for the manufacture of inorganic fertilizers. Phosphate gypsum is a product of technogenic origin as opposed to natural gypsum stone composed of CaSO 4 X 2 H 2 O. This is why the latter has a considerable amount of impurities (8 to 19%), which are rare earth and compounds of other elements. The content of the rare earth element is within 0.5 to 1.1% depending on the composition of the apatite concentrate.
희토류 원소를 인산석고로부터 회수하는 것과 관련하고 25% 황산 용액을 사용한 인산석고의 가공을 수반하는 공지된 방법(RF 특허 N 2225892 MPK C22B 59/00 참조)이 있다. 희토류 원소의 회수율는 50.0 내지 60.2% 이다. 그러한 황산 공정의 시간은 3시간이고; 황산 농도는 2 내지 3과 같은 고체-액체 비율을 갖는 20 내지 25 중량%이다. 희토류 원소의 결정화는 희토류 원소의 아황산염을 100을 초과하는 고체-액체 비율로 접종함으로써 수행된다. 그러한 기술은 그 생성이 많은 양의 가공 기구를 수반하는 것을 요구한다. 그 외에, 이 방법의 단점은 희토류 원소의 낮은 회수율, 상당한 수의 가공 작업, 순환(cycling)하는 황산 용액의 큰 부피 및 시간 소모를 포함한다.There is a known method involving the recovery of rare earth elements from phosphate gypsum and the processing of phosphoric acid gypsum using a 25% solution of sulfuric acid (see RF Patent N 2225892 MPK C22B 59/00). The recovery rate of the rare earth element is 50.0 to 60.2%. The time of such a sulfuric acid process is 3 hours; The sulfuric acid concentration is 20 to 25 wt.% With a solid-liquid ratio of 2 to 3. The crystallization of the rare earth element is carried out by inoculating the sulfite of the rare earth element at a solid-liquid ratio of more than 100. Such a technique requires that the production involves a large amount of processing equipment. In addition, the disadvantages of this process include low recovery of rare earth elements, a significant number of processing operations, large volumes of cycling sulfuric acid solution and time consuming.
희토류 원소 및 인광물질(phosphor)의 화합물을 용액 내로 22 내지 30%의 황산 용액에 의한 가공을 사용하여 20 내지 25분 이내의 많은 양의 황산 및 인산을 함유하는 불용성 석고 잔류물로 형성하는 추출을 수반하는 또 다른 공지된 방법(RF 특허 N 2337897, MPK C 01F 11/46)이 있다. 그 추출 용액 또한 나트륨 또는 칼륨을 갖는 희토류 원소의 이중 술페이트를 함유한다. 생성된 결정성 석고는 황산 및 인산의 잔류물의 산을 제거하기 위해 그들의 pH-값이 5를 초과하지 않는다면 Ca(OH)2, CaO 또는 CaCO3로 가공이 가해진다. 동시에 사용된 액체에서 인광물질 불순물의 함량을 조절하는 것과, 그들의 함량 대 잔류 석고 습도의 비율에 따라 이 사용된 액체에 TiOSO4H2O를 사용하여 허용되는 P2O5 함량이 얻어질 때까지 추출 또는 정제 공정을 가하는 것이 요구된다.The extraction of rare earth elements and phosphorus compounds into solution into an insoluble gypsum residue containing large amounts of sulfuric acid and phosphoric acid within 20 to 25 minutes using a treatment with a sulfuric acid solution of 22 to 30% (RF patent N 2337897, MPK C 01F 11/46). The extraction solution also contains a double sulfate of a rare earth element with sodium or potassium. The resulting crystalline gypsum is processed with Ca (OH) 2 , CaO or CaCO 3 unless their pH-value exceeds 5 to remove acids from the sulfuric acid and phosphoric acid residues. As adjusting the content of the phosphorescent dopant material in the liquid used at the same time, their content for the residual humidity rate of the plaster P 2 are allowed by using the H 2 O TiOSO 4 in the liquid used according to the O 5 It is required to apply an extraction or purification process until the content is obtained.
이 방법은 최대 82.1% 희토류 원소의 추출 용액 내로의 추출과 함께 최대 68.5%의 회수율로의 농축물 내로의 결정화에 의한 그들의 추가 분리를 달성하게 한다. This method achieves their further separation by crystallization into a concentrate at a maximum recovery rate of 68.5% with extraction into an extraction solution of up to 82.1% rare earth elements.
이 방법의 단점은 허용된 구축 표준에 따르지 않은 생성된 결정성 석고의 pH-값 및 P2O5의 높은 농도이다. 과포화 추출 용액으로부터의 란탄족 원소의 분리는 오히려 시간-소모적인 방법(2시간)이다. 산 추출제 내의 인광물질 불순물 및 석고 잔류물의 잔류 습도의 함량은 조절되어야만 한다. 과량의 인광물질을 제거하기 위해서, 티타닐 포스페이트를 추가 분리하며 농축된 황산을 사용하는 의무적인 공정과 함께 건조 티타늄 화합물 또는 티타늄의 혼합물 및 농축된 황산을 사용하여 인 화합물의 산을 제거하는 특수한 기구가 필요하다. 22% 미만으로 감소된 추출 용액 내의 황산의 농도의 경우에서, 다시 방법에서 사용될 수 있도록 황산 농도는 회수되어야 한다. 이는 희토류 원소의 추출, 상이한 추출 용액의 저장 및 인 화합물의 산 제거에 사용될 많은 양의 반응기, 용량성 및 여과 기구를 요구할 것이다.The disadvantage of this method is the pH-value of the produced crystalline gypsum and the high concentration of P 2 O 5 not conforming to the accepted building standard. The separation of the lanthanide elements from the supersaturated extraction solution is rather time-consuming (2 hours). The content of phosphorus impurities in the acid extractant and the residual humidity of the gypsum residues must be controlled. In order to remove excess phosphorus, a special mechanism to remove the acid of the phosphorus compound using a mixture of dry titanium compound or titanium and concentrated sulfuric acid with the mandatory process of further separating titanyl phosphate and using concentrated sulfuric acid . In the case of the concentration of sulfuric acid in the extraction solution reduced to less than 22%, the sulfuric acid concentration should be recovered so that it can be used again in the process. This will require large amounts of reactors, capacities and filtration equipment to be used for extraction of rare earth elements, storage of different extraction solutions and acid removal of phosphorus compounds.
인회석으로부터 용액 내에서 85% 분리로 인광물질 및 불소를 함유하는 희토류 원소의 회수를 하는 공지된 질산 기술(문헌 [V.D. Kosynkin et al. "State of the Art and Development Perspectives of Rare-Earth Industry in Russia"- "Metals", N 1, 2001])이 있다. A known nitric acid technique (see VD Kosynkin et al., &Quot; State of the Art and Development Perspectives of Rare-Earth Industry in Russia ") is used to recover rare earth elements containing phosphorescent and fluorine with 85% - "Metals ", N 1, 2001).
특허청구된 방법과 가장 유사한 것은 인산석고로부터 희토류 원소를 회수하는 방법으로 용액 내로의 희토류 원소의 추가 추출과 함께 황산으로의 인산석고의 가공, 불용성 석고 잔류물의 분리, 희토류 원소의 농축물을 결정화하기 위해 과포화 용액 내에서 희토류 원소의 함량의 증가, 사용된 액체로부터 농축물의 분리 및 그의 가공을 수반하는 것이다. 인산석고는 불용성 잔류물의 분리 이전에 용액으로부터 희토류 원소의 자발적인 결정화를 피하기 위해 1.8 내지 2.2의 액체-고체 비율에서 22 내지 30 중량% 농도의 황산을 20 내지 30 분 이내로 사용하여 가공된다. 과포화 용액은 0.4 내지 1.2 g/l의 나트륨 함량으로 얻어진다. The most similar to the claimed method is the extraction of the rare earth element from the phosphate gypsum, the further extraction of the rare earth element into the solution, the processing of the phosphorus acid gypsum with sulfuric acid, the separation of the insoluble gypsum residue, the crystallization of the rare earth element concentrate The increase of the content of rare earth elements in the supersaturated solution, the separation of the concentrate from the used liquid and the processing thereof. Phosphate gypsum is processed using sulfuric acid at a concentration of 22-30% by weight in a liquid-solid ratio of 1.8-2.2 within 20-30 minutes to avoid spontaneous crystallization of the rare earth element from the solution prior to separation of insoluble residues. The supersaturated solution is obtained with a sodium content of 0.4 to 1.2 g / l.
이 공지된 방법의 단점은 추가 시약의 요구, 상당한 부피와 함께 높은 농도인 산, 희토류 원소의 불충분한 회수율을 갖는 수많은 기초적 전문적 작업 및 방법의 전체적인 복잡성이다. A disadvantage of this known process is the overall complexity of numerous basic professional tasks and methods with the requirement of additional reagents, a considerable volume, and an insufficient recovery of acids, rare earth elements with high concentrations.
본 발명의 목적은 추출 용액 내로의 희토류 원소의 회수율의 향상 및 방법의 간략화와 함께 보조 시약의 감소, 산성 시약의 약화 및 또한 기초적 전문적 작업의 감소로 인한 인산석고로부터 희토류 원소의 추출 회수 효율을 향상시키는 전문적인 결과를 얻는 것이다.It is an object of the present invention to improve extraction recovery efficiency of rare earth element from phosphoric acid gypsum by reduction of auxiliary reagent, weakening of acid reagent and reduction of basic professional work with improvement of recovering rate of rare earth element into extraction solution and simplification of method To get professional results.
추출 현탁제를 혼합하면서 인산석고로부터 희토류 원소의 산성 추출, 추출 용액으로부터 결정성 인산석고의 불용성 잔류물의 분리 및 추출 용액으로부터 희토류 원소의 회수를 포함하는 인산석고로부터 희토류 원소를 회수하는 방법인 본 발명에 따라, 산성 추출은 3.2 내지 1.2 비율의 갖는 황산-질산 혼합물을 1 내지 3 중량%의 농도로, 4 내지 5의 고체-액체 비율로 8 내지 12분 이내로 사용하면서 동시에 혼합되는 추출 현탁제에 유체 음파 효과(hydroacoustic effect)를 생성하여 수행되고, 추출 용액으로부터 희토류 원소의 회수는, 그 차례에서, 추출 용액을 양이온-교환 필터를 통과시킴으로써 양이온-교환 수착을 사용하여 수행되는 것에 의해 전문적인 결과가 달성된다. The present invention relates to a method for recovering a rare earth element from a phosphate gypsum comprising acidic extraction of a rare earth element from the phosphate gypsum, separation of the insoluble residue of the crystalline phosphate gypsum from the extraction solution and recovery of the rare earth element from the extraction solution, , The acidic extraction is carried out using a sulfuric acid-nitric acid mixture having a ratio of 3.2 to 1.2 in a concentration of 1 to 3% by weight, in a solid-liquid ratio of 4 to 5 within 8 to 12 minutes, The recovery of the rare earth element from the extraction solution is performed in that order by performing a cation-exchange sorption by passing the extraction solution through a cation-exchange filter, thereby producing a professional result .
희토류 원소가 없는 추출 용액은 인산석고 산성 추출의 단계에서의 추가 사용을 위해 재생될 수 있고, 양이온-교환 필터의 흡착제에 결합한 희토류 원소는 후자가 재생될 때 분리된다. The extraction solution without the rare earth element can be regenerated for further use in the step of gypsum acid extraction, and the rare earth element bound to the adsorbent of the cation-exchange filter is separated when the latter is regenerated.
실험에 의해 증명된 바와 같이, 니트로-셀룰로오스를 생성하면서 형성된 산성 폐기물이 황산-질산 혼합물로 사용될 수 있다.As demonstrated by experimentation, acid wastes formed while generating nitro-cellulose can be used as a sulfuric acid-nitric acid mixture.
전문적인 결과를 달성하게 하는 특허청구된 발명의 본질적인 특징은 하기와 같다. Essential features of the claimed invention to achieve professional results are as follows.
인산석고가 황산-질산 혼합물을 사용하여 가공될 때, 희토류 원소는 황산 및 질산과 상호작용한다. 황산과의 상호작용의 결과로서 희토류 원소는 10분 이내로 용해되고, 동시에 인산석고로부터의 나트륨 및 칼륨 양이온이 용액에 들어가서 그 안에서 희토류 원소와 이중 술페이트를 형성한다. 희토류 원소와 나트륨 및 희토류 원소와 칼륨 - 둘 모두의 이중 술페이트의 용해도는 황산 용액에서 낮고(문헌[E.P. Lokshin et al. “Recovery Issues of Rare Earth Metals During Sulfuric Processing of Khibin Apatite Concentrate”-“Metals", N 1, 2001] 참조), 질산 에서는 우수하다. When the phosphate gypsum is processed using a sulfuric acid-nitric acid mixture, the rare earth element interacts with sulfuric acid and nitric acid. As a result of the interaction with sulfuric acid, the rare earth element dissolves within 10 minutes, while the sodium and potassium cations from the phosphate gypsum enter the solution and form a double sulfate with the rare earth element therein. The solubility of the rare earth element and the sodium and the rare earth element and the potassium sulfate-both double sulfates is low in sulfuric acid solution (EP Lokshin et al., &Quot; Recovery Issues of Rare Earth Metals During Sulfuric Processing of Khibin Apatite Concentrate " , N 1, 2001), and is excellent in nitric acid.
동시의 유체 음파 작용과 함께 상기 산의 혼합물의 특정 비율 및 농도는 인산석고로부터 희토류 원소의 더 완전한 회수를 위한 조건을 제공한다는 것이 실험에 의해 증명되었다.Experiments have demonstrated that certain ratios and concentrations of the mixture of acids with simultaneous hydrofine action provide conditions for a more complete recovery of the rare earth element from the gypsum.
4 내지 5의 액체-고체 비율에서 황산-질산 혼합물을 사용하여 수행된 산 추출은 석고 분리 이전에 희토류 원소의 결정화의 가능성을 배제하며 또한 추출기 내에서 및 또한 제제가 회전-진동 기기를 통과할 때 현탁제의 안정적인 혼합을 가능케 하는데 최적이다. 황산 및 질산의 혼합물의 사용은 석고 결정으로부터 다른 불순물의 완전한 분리에 기여한다.Acid extraction performed using a sulfuric acid-nitric acid mixture at a liquid-solid ratio of 4 to 5 eliminates the possibility of crystallization of the rare earth element prior to gypsum separation and also in the extractor and also when the formulation is passed through a rotary- It is optimal to enable stable mixing of the suspension. The use of a mixture of sulfuric acid and nitric acid contributes to complete separation of other impurities from gypsum crystals.
희토류 원소의 화합물 및 다른 불순물과 황산 및 질산의 상호작용에 요구되는 최적의 시간(8 내지 12분)은 인산석고 추출 현탁제에의 지속적인 유체 음파 작용으로 인해 가능하다. 현탁제는 회전-진동 기기의 작업 구성요소를 통과하고, 석고는 집중적인 기계적 분쇄를 받아 10 내지 15 μm 입자를 가지며, 초음파 주파수에 상응하는 파라미터에서 캐비테이션(cavitation)을 받는다. 이는 특히 150 내지 250 mm 직경인 작업 구성요소를 갖는 회전-진동 기기의 작동 모드 및 50 Hz의 회전 속도에 의해 보장된다. 회전-진동 기기에서의 상기 파라미터는 그의 회전자(rotor) 및 고정자(stator) 사이의 미궁 공간(labyrinth space)(10 내지 15 μm)내의 현탁제에 집중적인 효과를 생성하고, 결정의 기계적 파괴와 함께 캐비테이션은 물질-전달 과정을 상당히 더 빠르게 일으킨다. 그러한 초음파 노출은 더 집중적인 물리적 및 화학적 과정을 생성하는데 사용되는 것으로 공지되어 있다(L.D. Rosenberg “Ultrasonics”, M., 1956 참조).The optimum time (8 to 12 minutes) required for the interaction of the rare earth element compounds and other impurities with sulfuric acid and nitric acid is possible due to the continuous hydrofine action on the phosphate gypsum extraction suspension. The suspension passes through the working components of the rotating-vibration machine, the gypsum undergoes intensive mechanical grinding and has 10 to 15 μm particles, cavitation in parameters corresponding to the ultrasonic frequency. This is particularly ensured by the operating mode of the rotary-vibration machine with a working component with a diameter of 150 to 250 mm and a rotation speed of 50 Hz. The parameter in the rotating-oscillating machine produces an intensive effect on the suspension in the labyrinth space (10-15 [mu] m) between its rotor and stator, Together, cavitation generates the mass-transfer process considerably faster. Such ultrasound exposure is known to be used to generate more intensive physical and chemical processes (see L. D. Rosenberg " Ultrasonics ", M., 1956).
추출 과정이 끝난 후에, 현탁제는 분리 단위장치, 예를 들면 결정성 석고가 용액으로부터 분리될 원심 분리기 또는 필터로 기울여 따라내어진다.After the extraction process, the suspension is tilted with a separation unit, for example, a centrifuge or filter to separate the crystalline gypsum from the solution.
용액은 희토류 원소 및 인광물질의 화합물을 수착하는 화합물을 함유하는 양이온-교환 필터에 공급된다. 양이온-교환 필터를 이탈한 용액은 황산 및 질산의 수용액이고 산의 일부분이 회수된 후에 다시 과정에서 사용될 수 있다. 희토류 원소의 잔류물은 양이온-교환 필터의 작업 표면으로부터 분리되고, 필터는 희토류 원소의 추가 수착에 사용될 수 있다.The solution is fed to a cation-exchange filter containing a compound adsorbing a rare earth element and a compound of the phosphor. The solution leaving the cation-exchange filter is an aqueous solution of sulfuric acid and nitric acid and can be used again in the process after a portion of the acid has been recovered. The residue of the rare earth element is separated from the working surface of the cation-exchange filter, and the filter can be used for further sorption of the rare earth element.
상이한 방법을 사용하여 니트로-셀룰로오스를 생성하는 동안 형성된 소위 산성 폐기물의 혼합물의 사용은 실험에 의해 증명되었다. 실험적 결과는 희토류 원소의 회수율이 3 중량% 농도의 산을 사용할 때 얻어진 비율에 가깝다는 것을 보여준다.The use of a mixture of so-called acidic wastes formed during the production of nitro-cellulose using different methods has been demonstrated by experimentation. Experimental results show that the recovery of rare earth elements is close to that obtained when using an acid at a concentration of 3% by weight.
본 발명의 상기 특징은 방법의 실현을 보장하고 시약량과 소모 및 기술적인 과정과 기본 단위의 로딩에 필요한 시간을 감소하게 한다. 그들은 또한 일반적으로 희토류 원소의 회수율을 증가시키고 기술적인 과정을 최적화하는 것을 돕는다.This feature of the present invention ensures the realization of the method and reduces the amount of reagent, consumption and time required for technical processes and loading of the basic unit. They also generally help to increase the recovery of rare earth elements and optimize the technical process.
특허청구된 방법의 본질은 하기 실시예로부터 이해될 수 있다.The nature of the claimed process can be understood from the following examples.
실시예:Example:
실시예 1Example 1
0.45%의 희토류 원소를 함유하는 폐기 (인회석) 인산석고 100 kg을 5의 액체-고체 비율로 황산-질산 혼합물의 1 중량% 용액을 10분 이내로 사용하여 대용량 탱크-추출기에서 혼합하면서 가공했다. 황산 및 질산은 혼합물에 3 : 1의 비율(중량부)에 상응하게 함유되었다. 추출 과정 동안 현탁제를 혼합했고 회전-진동 기기를 통해 순환할 때와 동시에 유체 음파 노출을 10분 이내로 가했다. 이들 파라미터는 현탁제에 필요한 안정성 및 그 위에 가해진 유체 음파 작용을 보장한다. 회전-진동 기기의 회전자 직경은 150 mm이고, 그것의 회전 빈도는 50 Hz이며, 공급 속도는 5 m3/h이다. 결정성 인산석고로부터 용액을 분리하기 위해 생성된 현탁제는 원심분리에서 가공하였다. 100 kg of waste (apatite) phosphate gypsum containing 0.45% rare earth element was processed with mixing in a large tank-extractor using a 1 wt% solution of a sulfuric acid-nitric acid mixture in a liquid-solid ratio of 5 within 10 minutes. Sulfuric acid and nitric acid were contained in the mixture in a proportion of 3: 1 (parts by weight). The suspension was mixed during the extraction process and at the same time as the circulation through the rotary-vibration device, the hydro-acoustic wave exposure was applied within 10 minutes. These parameters ensure the stability required for the suspending agent and the hydrothermal action exerted thereon. The rotor diameter of the rotating-vibration machine is 150 mm, its rotation frequency is 50 Hz, and the feed rate is 5 m 3 / h. The resulting suspension to separate the solution from crystalline gypsum was processed in a centrifuge.
ICPMS(귀납적 결합 혈장 진량 분광측정법)을 사용한 샘플의 분석은 희토류 원소의 회수율이 86.1%와 같다는 것을 보여준다.Analysis of the sample using ICPMS (Inductively Coupled Plasma Atomic Spectroscopy) shows that the recovery of the rare earth element is equal to 86.1%.
희토류 원소를 함유하는 용액을 양이온-교환 필터에 통과시켰다. 양이온-교환 필터상에서의 희토류 원소의 농축물은 방법의 생성된 생성물이었다. 회수율은 86.1%였다. 산성 추출제는 (양이온-교환 필터를 통과한 후에 재생됨) 재사용되었다. The solution containing the rare earth element was passed through a cation-exchange filter. The concentrate of the rare earth element on the cation-exchange filter was the resultant product of the process. The recovery rate was 86.1%. The acidic extractant (recycled after passing through the cation-exchange filter) was reused.
수행된 실험을 기준으로 한 희토류 원소의 회수율은 하기 표에 나타나 있다.The recovery rates of the rare earth elements based on the experiments performed are shown in the following table.
상기 실시예 및 표에서 볼 수 있듯이, 특허청구된 방법은 인산석고로부터 희토류 원소의 회수율을 최대 85 내지 86.1%로 증가시키고 추출 과정의 시간을 절반으로 감소시켜 더 적은 시약을 더 낮은 농도로 그리고 산성 시약을 더 적은 부피로 사용하게 하며 기술적인 작업의 수를 감소시킨다. As can be seen from the above examples and tables, the claimed process increases the recovery of rare earth elements from phosphorous gypsum to a maximum of 85 to 86.1% and reduces the time of the extraction process in half, Allows reagents to be used in smaller volumes and reduces the number of technical tasks.
특허청구된 방법은 회전-진동 기기 및 양이온-교환 필터를 함께 갖춘 표준 기구가 사용될 경우 산업 분야에 이용 가능하다. The claimed method is applicable to industrial applications where standard instruments with rotating-vibration devices and cation-exchange filters are used.
Claims (3)
황산과 질산을 3.2:1 내지 1.2:1의 중량비로 포함하는 혼합물(이때, 혼합물의 농도는 1 내지 3 중량%임)을
4:1 내지 5:1의 액체:고체의 중량비로 8 내지 12분 동안 혼합하여 현탁액을 형성하는 단계;
인산석고 입자를 10 내지 15 μm의 크기로 분쇄하는 회전-진동 기기를 사용하여 혼합과 동시에 현탁액 상에 유체 음파 효과(hydroacoustic effect)를 제공하는 단계;
현탁액으로부터 불용성 결정성 석고 잔류물을 분리하여 추출 용액을 수득하는 단계; 및
추출 용액을 양이온-교환 필터를 통해 통과시킴으로써 추출 용액으로부터 희토류 원소를 추출하는 단계를 포함하는, 산성 추출에 의해 인산석고로부터 희토류 원소를 추출하는 방법.Phosphate gypsum, and
A mixture comprising sulfuric acid and nitric acid in a weight ratio of 3.2: 1 to 1.2: 1, wherein the concentration of the mixture is 1 to 3% by weight,
Mixing in a weight ratio of liquid to solids of from 4: 1 to 5: 1 for from 8 to 12 minutes to form a suspension;
Providing a hydroacoustic effect on the suspension simultaneously with mixing using a rotary-vibration apparatus for pulverizing phosphate gypsum particles to a size of 10 to 15 탆;
Separating the insoluble crystalline gypsum residue from the suspension to obtain an extraction solution; And
Extracting the rare earth element from the gypsum by acidic extraction, comprising extracting the rare earth element from the extraction solution by passing the extraction solution through a cation-exchange filter.
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