CN1605639A - Process for clean conversion of tantalum niobium ore - Google Patents

Process for clean conversion of tantalum niobium ore Download PDF

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CN1605639A
CN1605639A CN 200310100023 CN200310100023A CN1605639A CN 1605639 A CN1605639 A CN 1605639A CN 200310100023 CN200310100023 CN 200310100023 CN 200310100023 A CN200310100023 A CN 200310100023A CN 1605639 A CN1605639 A CN 1605639A
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potassium
solution
niobium
tantalum
niobate
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CN1238536C (en
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周宏明
郑诗礼
张懿
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Institute of Process Engineering of CAS
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Institute of Process Engineering of CAS
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Abstract

The clean Ta/Nb ore converting process includes decomposing Ta/Nb ore in KOH and molten salt, diluting and separating decomposed product to obtain high concentration KOH solution and solid phase connecting potassium titanate/niobate, hot water leaching and separating potassium hexatitanate/hexaniobate solution and iron-manganese slag precipitate containing insoluble potassium metatitanate/metaniobate; regulating pH value of hexatitanate/hexaniobate solution to alkali to obtain hexatitanate/hexaniobate crystal and reusable crystalline mother liquid; and decomposing potassium metatitanate/metaniobate and iron-manganese slag with HCl solution to obtain metatitanate/metaniobate crystal. The said process has no fluorine ion pollution and high ore decomposing rate, and may produce potassium titanate/niobate as intermediate for producing various Ta/Nb products.

Description

A kind of tantalum niobium concentrate cleaning transforming method
Technical field
The present invention relates to a kind of tantalum niobium concentrate method for transformation, particularly relate to a kind of sour potassium (K of six tantalums (niobium) that from the raw material that contains tantalum and niobium, extracts 8(Ta, Nb) 6O 19NH 2O) and partially the sour potassium of tantalum (niobium) (K (Ta, Nb) O 3) cleaning transforming method.
Technical background
All adopt high dense HF acid (>60%) or high dense HF-H at present both at home and abroad 2SO 4Mixing acid disaggregating treatment tantalum niobium concentrate, this technology HF acid consumption is big, and 10% the HF of having an appointment becomes the main gas contact scar of tantalum niobium metallurgy with the form discharging of waste gas; Also produce a large amount of fluorites, calcium sulfate residue in the liquid waste disposal process, 1 ton of ore of every processing can produce 10~15 tons of this residues, and environmental pollution is very serious, and this technology is low to the rate of decomposition of the tantalum niobium concentrate of difficulty decomposition, has only about 85%.
Though the tantalum niobium resource of China is abundant, grade is low, belongs to the difficult ore deposit of decomposing, and is unsuitable for adopting the HF acid system.Along with the increase of tantalum, niobium goods demand, high-grade tantalum niobium hard-rock mine far can not satisfy the needs in market, and therefore, low-grade, difficult reasonable utilization of decomposing the tantalum niobium raw material has put on the agenda.
In recent years, under the pressure of environmental protection pressure, German H.C.Starc company improves the internal recycling approach of wet processing by concentrating research, to reduce H 2SO 4Deng the consumption of chemical feedstocks and the quantity of slag, and reclaim HF (seeing patent DE402107, US5209910,1993) in the various waste material liquid, but this technology can't be used separately for handling low grade ore.Free HF and elevated temperature heat that United States Patent (USP) (US4309389, US6338832 etc.) has proposed in the vacuum-evaporation recovery raffinate are decomposed the method that contains fluorine residue recovery HF.These methods all belong to the cost height generally, and little end treatment produces effects.
Summary of the invention
It is big to the objective of the invention is to overcome prior art HF acid consumption, and environmental pollution is serious, and the rate of decomposition of the tantalum niobium concentrate that difficulty is decomposed is low, the cost height, the little defective of producing effects, thus a kind of discharging that reduces highly toxic HF acid waste gas, waste water, waste residue is provided, cut down F from beginning of production -Pollution, and increase substantially difficult tantalum (niobium) rate of recovery of decomposing the ore deposit, obtain the tantalum niobium concentrate cleaning transforming method of good economic benefit and environmental benefit.
Tantalum niobium concentrate cleaning transforming method provided by the invention, its principle are that tantalum niobium concentrate is decomposed in the inferior fused salt of potassium hydroxide, and its reaction formula is as follows:
......(1)
......(2)
Utilize the dissolubility difference of the sour potassium of six tantalums (niobium) in different concns KOH solution then, be insoluble to the characteristic of HCl with the sour potassium of inclined to one side tantalum (niobium), transfer sour potassium of alkali crystallization purifying six tantalums (niobium) and acid to decompose the crystallization of the ferrimanganic inclined to one side tantalum of slag purifying (niobium) potassium to it respectively, obtain impure amount sour potassium of six tantalums (niobium) seldom and the sour potassium crystallization of tantalum (niobium) partially, as the intermediate of the serial tantalum of preparation, niobium product.
The objective of the invention is to be achieved through the following technical solutions:
The invention provides a kind of tantalum niobium concentrate cleaning transforming method, this method is after tantalum niobium concentrate is decomposed in the inferior fused salt of potassium hydroxide, isolate sour potassium crystallization of water miscible six tantalums (niobium) and the sour potassium crystallization of insoluble inclined to one side tantalum (niobium), both all can be used as the intermediate of the serial tantalum of preparation, niobium product, and this method may further comprise the steps:
(1) decompose tantalum niobium concentrate: at 280~340 ℃, under the stirring condition, it is in the inferior fused salt of 75~85wt% potassium hydroxide that tantalum niobium concentrate is added concentration, carries out decomposition reaction 1~8 hour, and the mass ratio of potassium hydroxide and tantalum niobium concentrate is 3~7: 1;
(2) dilution degradation production: at 20 ℃~110 ℃, the tantalum niobium concentrate degradation production that dilute with water step (1) obtains concentration of potassium hydroxide to the solution is 550~750g/L, filter, obtain potassium tantalate or/and the crude product of potassium niobate, and impure amount potassium hydroxide strong solution seldom, this potassium hydroxide strong solution is returned step (1) and is used to carry out decomposition reaction behind dehydration by evaporation;
(3) leaching separates: at 60~100 ℃, the potassium tantalate that step (2) is made is or/and the crude product concentration of potassium niobate is the potassium hydroxide solution leaching of 60~200g/L, obtained leaching six easily molten potassium tantalates or/and the leach liquor of six potassium niobates, with the inclined to one side potassium tantalate that is insoluble to potassium hydroxide solution or/and potassium niobate and ferrimanganic slag solid partially;
(4) purifying six potassium tantalates are or/and six potassium niobates: at 20~40 ℃, six potassium tantalates that step (3) is obtained are or/and six potassium niobate leach liquors, it is 350~600g/L that adding potassium hydroxide makes the concentration of potassium hydroxide of leach liquor, separates out six potassium tantalates or/and six potassium niobate crystallization (K 8Ta 6O 19NH 2O is or/and K 8Nb 6O 19NH 2O), crystalline mother solution returns step (1) and is used to carry out decomposition reaction behind dehydration by evaporation;
(5) the inclined to one side potassium tantalate of purifying is or/and inclined to one side potassium niobate: at 40~80 ℃, the inclined to one side potassium tantalate that step (3) is obtained or/and partially potassium niobate and ferrimanganic slag solid to add concentration be the hydrochloric acid of 10~20v%, solid-to-liquid ratio is 1: 1~4, resolving time is 5~30 minutes, and the inclined to one side potassium tantalate that obtains purifying is or/and inclined to one side potassium niobate crystallization (KTaO 3Or/and KNbO 3) and acid decomposition liquid.
Compared with the prior art, the advantage of tantalum niobium concentrate cleaning transforming method provided by the invention is:
1, the present invention uses the KOH sub-molten salt method to handle tantalum niobium concentrate, compares with traditional HF acid decomposition, has stopped F from beginning of production -Pollution, have huge environmental benefit;
2, present method can reach more than 99.0% the rate of decomposition of the low-grade tantalum niobium concentrate of difficulty decomposition, and is higher more than 15% than traditional HF acid system, greatly improved resource utilization;
3, the liquid phase flow of present method is fine, can greatly strengthen reaction and transmission, thereby can shorten the reaction times significantly, enhances productivity, and compares with traditional HF acid system, and the resolving time of tantalum niobium concentrate is by being kept to 1~8 hour more than 20 hours;
4, the present invention has greatly reduced starting material ground and has consumed owing to realized the internal recycling of alkali, and KOH does not have process loss, and alkali consumption is the 0.5kg/kg ore deposit, and one ton of tantalum niobium concentrate of the every smelting of traditional HF acid system on average consumes 4 tons of acid, and production cost reduces greatly.
Description of drawings
Fig. 1 is the process flow sheet of tantalum niobium concentrate cleaning transforming method provided by the invention.
Embodiment
Below by further setting forth this implementation of processes process and step in conjunction with the accompanying drawings and embodiments.
Embodiment 1,
The potassium hydroxide alkaline solution that reactor is returned in circulation adds-200 purpose tantalum niobium concentrates through heat temperature raising to 300 ℃, and alkaline solution: the mass ratio of tantalum niobium concentrate is 4: 1, under agitation mixes fully, reacts 3 hours, obtains degradation production;
At 30 ℃, the above-mentioned degradation production of dilute with water to the KOH concentration in the solution is 600g/L, filters, and obtains containing the crude product of the sour potassium of tantalum (niobium), and impure amount potassium hydroxide strong solution seldom, this potassium hydroxide strong solution can be used for above-mentioned steps and carries out decomposition reaction behind dehydration by evaporation;
At 70 ℃, after the crude product concentration that will contain the sour potassium of tantalum (niobium) was the potassium hydroxide solution leaching 30min of 88g/L, filtered while hot obtained containing the sour potassium (K of six tantalums (niobium) 8(Ta, Nb) 6O 19NH 2O) solution and contain the sour potassium of inclined to one side tantalum (niobium) (K (Ta, Nb) O 3) ferrimanganic slag precipitation;
At 30 ℃, it is 480g/L that adding KOH makes the KOH concentration in the sour potassium solution of six tantalums (niobium), ageing 3 hours, obtain the sour potassium crystallization of six tantalums (niobium), wherein contain Ta:16.1%, Nb:15.1%, Fe: do not detect, Mn:0.03%, Ti:0.12%, crystalline mother solution can return inferior fused salt decomposition step through dehydration by evaporation and be used to carry out decomposition reaction;
At 50 ℃, the ferrimanganic slag precipitation that will contain the sour potassium of inclined to one side tantalum (niobium) adds 15v% (volume ratio) HCl and handles 30min, solid-to-liquid ratio 1: 4, obtain the sour potassium precipitation of inclined to one side tantalum (niobium) of purifying, wherein contain Ta:34.2%, Nb:23.9%, Fe:0.24%, Mn: do not detect Ti:1.5%;
The sour potassium of six tantalums (niobium) of gained or the inclined to one side sour potassium of tantalum (niobium), all in simple substance, foreign matter content is low, is easy to carry out tantalum, niobium extracting and separating.
Embodiment 2
The potassium hydroxide alkaline solution that reactor is returned in circulation adds the difficult tantalum niobium enrichment slag that decomposes of-200 purposes through heat temperature raising to 340 ℃, and alkaline solution: the difficult mass ratio that decomposes tantalum niobium enrichment slag is 3: 1, under agitation mixes fully, reacts 1 hour, obtains degradation production;
At 20 ℃, the above-mentioned degradation production of dilute with water to the KOH concentration in the solution is 550g/L, filters, and obtains containing the crude product of the sour potassium of tantalum (niobium), and impure amount potassium hydroxide strong solution seldom, this potassium hydroxide strong solution can be used for above-mentioned steps and carries out decomposition reaction behind dehydration by evaporation;
At 60 ℃, after the crude product concentration that will contain the sour potassium of tantalum (niobium) was the potassium hydroxide solution leaching 40min of 60g/L, filtered while hot obtained containing the sour potassium (K of six tantalums (niobium) 8(Ta, Nb) 6O 19NH 2O) solution and contain the sour potassium of inclined to one side tantalum (niobium) (K (Ta, Nb) O 3) ferrimanganic slag precipitation;
At 20 ℃, it is 350g/L that adding KOH makes the KOH concentration in the sour potassium solution of six tantalums (niobium), ageing 3 hours, obtain the sour potassium crystallization of six tantalums (niobium), wherein contain Ta:15.8%, Nb:15.3%, Fe: do not detect, Mn:0.04%, Ti:0.1%, crystalline mother solution can return inferior fused salt decomposition step through dehydration by evaporation and be used to carry out decomposition reaction;
At 80 ℃, the ferrimanganic slag precipitation that will contain the sour potassium of inclined to one side tantalum (niobium) adds 10v% (volume ratio) HCl and handles 15min, solid-to-liquid ratio 1: 2, obtain the sour potassium precipitation of inclined to one side tantalum (niobium) of purifying, wherein contain Ta:33.8%, Nb:24.1%, Fe:0.26%, Mn: do not detect Ti:1.4%;
The sour potassium of six tantalums (niobium) of gained or the inclined to one side sour potassium of tantalum (niobium), all in simple substance, foreign matter content is low, is easy to carry out tantalum, niobium extracting and separating.
Embodiment 3
The potassium hydroxide alkaline solution that reactor is returned in circulation adds the difficult tantalum niobium enrichment slag that decomposes of-200 purposes through heat temperature raising to 280 ℃, and alkaline solution: the difficult mass ratio that decomposes tantalum niobium enrichment slag is 7: 1, under agitation mixes fully, reacts 8 hours, obtains degradation production;
At 110 ℃, the above-mentioned degradation production of dilute with water to the KOH concentration in the solution is 750g/L, filters, and obtains containing the crude product of the sour potassium of tantalum (niobium), and impure amount potassium hydroxide strong solution seldom, this potassium hydroxide strong solution can be used for above-mentioned steps and carries out decomposition reaction behind dehydration by evaporation;
At 100 ℃, after the crude product concentration that will contain the sour potassium of tantalum (niobium) was the potassium hydroxide solution leaching 40min of 200g/L, filtered while hot obtained containing the sour potassium (K of six tantalums (niobium) 8(Ta, Nb) 6O 19NH 2O) solution and contain the sour potassium of inclined to one side tantalum (niobium) (K (Ta, Nb) O 3) ferrimanganic slag precipitation;
At 40 ℃, it is 600g/L that adding KOH makes the KOH concentration in the sour potassium solution of six tantalums (niobium), ageing 3 hours, obtain the sour potassium crystallization of six tantalums (niobium), wherein contain Ta:16.0%, Nb:15.2%, Fe: do not detect, Mn:0.05%, Ti:0.15%, crystalline mother solution can return inferior fused salt decomposition step through dehydration by evaporation and be used to carry out decomposition reaction;
At 40 ℃, the ferrimanganic slag precipitation that will contain the sour potassium of inclined to one side tantalum (niobium) adds 20v% (volume ratio) HCl and handles 5min, solid-to-liquid ratio 1: 1, obtain the sour potassium precipitation of inclined to one side tantalum (niobium) of purifying, wherein contain Ta:33.6%, Nb:24.3%, Fe:0.28%, Mn: do not detect Ti:1.6%;
The sour potassium of six tantalums (niobium) of gained or the inclined to one side sour potassium of tantalum (niobium), all in simple substance, foreign matter content is low, is easy to carry out tantalum, niobium extracting and separating.

Claims (1)

1, a kind of tantalum niobium concentrate cleaning transforming method, this method may further comprise the steps:
(1) decompose tantalum niobium concentrate: at 280~340 ℃, under the stirring condition, it is in the inferior fused salt of 75~85wt% potassium hydroxide that tantalum niobium concentrate is added concentration, carries out decomposition reaction 1~8 hour, and the mass ratio of potassium hydroxide and tantalum niobium concentrate is 3~7: 1;
(2) dilution degradation production: at 20 ℃~110 ℃, the tantalum niobium concentrate degradation production that dilute with water step (1) obtains concentration of potassium hydroxide to the solution is 550~750g/L, filter, obtain potassium tantalate or/and the crude product of potassium niobate, and impure amount potassium hydroxide strong solution seldom, this potassium hydroxide strong solution is returned step (1) and is used to carry out decomposition reaction behind dehydration by evaporation;
(3) leaching separates: at 60~100 ℃, the potassium tantalate that step (2) is made is or/and the crude product concentration of potassium niobate is the potassium hydroxide solution leaching of 60~200g/L, obtained leaching six easily molten potassium tantalates or/and the leach liquor of six potassium niobates, with the inclined to one side potassium tantalate that is insoluble to potassium hydroxide solution or/and potassium niobate and ferrimanganic slag solid partially;
(4) purifying six potassium tantalates are or/and six potassium niobates: at 20~40 ℃, six potassium tantalates that step (3) is obtained are or/and six potassium niobate leach liquors, it is 350~600g/L that adding potassium hydroxide makes the concentration of potassium hydroxide of leach liquor, separate out six potassium tantalates or/and six potassium niobate crystallizations, crystalline mother solution returns step (1) and is used to carry out decomposition reaction behind dehydration by evaporation;
(5) the inclined to one side potassium tantalate of purifying is or/and inclined to one side potassium niobate: at 40~80 ℃, the inclined to one side potassium tantalate that step (3) is obtained or/and partially potassium niobate and ferrimanganic slag solid to add concentration be the hydrochloric acid of 10~20v%, solid-to-liquid ratio is 1: 1~4, resolving time is 5~30 minutes, and the inclined to one side potassium tantalate that obtains purifying is or/and inclined to one side potassium niobate crystallization and acid decomposition liquid.
CN 200310100023 2003-10-08 2003-10-08 Process for clean conversion of tantalum niobium ore Expired - Fee Related CN1238536C (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100516256C (en) * 2006-11-22 2009-07-22 中国科学院过程工程研究所 Mechanical activating strengthening alkali decomposition cleaning transforming method for hard-decomposition tantalum niobium concentrate
CN100554445C (en) * 2007-01-05 2009-10-28 中国科学院过程工程研究所 A kind of inclined to one side potassium tantalate, method of tantalum and niobium in the potassium niobate mixture partially of separating
CN103160684A (en) * 2011-12-15 2013-06-19 中国科学院过程工程研究所 Method for extracting tantalum and niobium through low alkali decomposition of tantalum-niobium ore
CN103572045A (en) * 2012-07-23 2014-02-12 中国科学院过程工程研究所 Alkali-acid combined technology for processing low-grade niobium-tantalum ore
CN103572046A (en) * 2012-07-23 2014-02-12 中国科学院过程工程研究所 Method for dissolving niobium-tantalum ore with KOH for extracting niobium and tantalum
CN106395903A (en) * 2016-08-31 2017-02-15 周口师范学院 Method for synthesis of hexaniobate and alkali metal salt using household microwave oven
CN115838872A (en) * 2023-02-13 2023-03-24 锦益创典(天津)科技有限责任公司 Filter pressing washing method for tantalum-niobium slurry decomposition liquid

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011010346B4 (en) 2011-02-04 2014-11-20 H.C. Starck Gmbh Process for the production of a homogeneous multi-substance system, ceramic material based on the homogeneous multi-substance system and its use

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100516256C (en) * 2006-11-22 2009-07-22 中国科学院过程工程研究所 Mechanical activating strengthening alkali decomposition cleaning transforming method for hard-decomposition tantalum niobium concentrate
CN100554445C (en) * 2007-01-05 2009-10-28 中国科学院过程工程研究所 A kind of inclined to one side potassium tantalate, method of tantalum and niobium in the potassium niobate mixture partially of separating
CN103160684A (en) * 2011-12-15 2013-06-19 中国科学院过程工程研究所 Method for extracting tantalum and niobium through low alkali decomposition of tantalum-niobium ore
CN103572045A (en) * 2012-07-23 2014-02-12 中国科学院过程工程研究所 Alkali-acid combined technology for processing low-grade niobium-tantalum ore
CN103572046A (en) * 2012-07-23 2014-02-12 中国科学院过程工程研究所 Method for dissolving niobium-tantalum ore with KOH for extracting niobium and tantalum
CN106395903A (en) * 2016-08-31 2017-02-15 周口师范学院 Method for synthesis of hexaniobate and alkali metal salt using household microwave oven
CN115838872A (en) * 2023-02-13 2023-03-24 锦益创典(天津)科技有限责任公司 Filter pressing washing method for tantalum-niobium slurry decomposition liquid

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