CN106916948B - A kind of saponification agent and its application method of rare earth organic extractant - Google Patents
A kind of saponification agent and its application method of rare earth organic extractant Download PDFInfo
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- CN106916948B CN106916948B CN201710131205.7A CN201710131205A CN106916948B CN 106916948 B CN106916948 B CN 106916948B CN 201710131205 A CN201710131205 A CN 201710131205A CN 106916948 B CN106916948 B CN 106916948B
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- 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
- C22B3/26—Treatment or purification of solutions, e.g. obtained by leaching by liquid-liquid extraction using organic compounds
- C22B3/38—Treatment or purification of solutions, e.g. obtained by leaching by liquid-liquid extraction using organic compounds containing phosphorus
- C22B3/384—Pentavalent phosphorus oxyacids, esters thereof
- C22B3/3844—Phosphonic acid, e.g. H2P(O)(OH)2
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- 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
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
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Abstract
The invention discloses the saponification agent and its application method of a kind of rare earth organic extractant, the saponification agent is made of sodium hydroxide and sodium carbonate, can be used for the saponification of the rare earths organic extractant such as P507.The present invention does not generate the product purity height that ammonia-nitrogen sewage, production cost are low, easy to operate, extraction efficiency is high, no third is mutually formed, obtained in extraction process.
Description
Technical field
The present invention relates to the technical fields of rare earth organic extraction, in particular to include the steps that the saponification of organic extractant
The technical field of rare earth organic extraction methods.
Background technique
During Rare Earth Production, in most cases, different rare earth elements are all to exist as a mixture, only
When finally needing to separate, just extracted respectively by different processing methods.
Technical maturity highest at present, most widely used Rare Earth Separation method is organic extraction methods, i.e., by organic
Extractant separates the different rare earth elements in lucium.During organic extraction, organic extractant composition
Organic phase and lucium can constantly carry out ion exchange, cause the extracting power of extractant constantly to decline, thus for drop
Low production cost improves extractant extraction yield, constantly has new technological development to come out.Such as Chinese patent application CN101602519A
In be mentioned in background technique, extracting process in the prior art is broadly divided into saponification organic extractant and is extracted, or makes
With non-saponified special organic extractant, wherein mainly passing through saponification agent ammonium hydroxide, carbonic acid using the method for saponification organic extractant
Hydrogen ammonium etc. adds raw material after being saponified to organic extractant and extracts, and this method can generate a large amount of ammonia nitrogen waste waters, causes
Environmental pollution；If using non-saponified organic extractant, high production cost is unfavorable for being mass produced.
Summary of the invention
It is an object of the invention to propose that one kind is pollution-free, production cost is low, easy to operate, extraction efficiency is high, extracted
The saponification of organic extractant used in the rare earth organic extraction process that no third is mutually formed in journey, obtained product purity is high
Agent, another object of the present invention is to disclose its application method.
The invention adopts the following technical scheme:
A kind of saponification agent of rare earth organic extractant, the saponification agent are made of sodium hydroxide and sodium carbonate.
Preferably: the mass ratio of the substance of sodium hydroxide and sodium carbonate is 1:2 in the saponification agent.
It is also preferred that: the saponification agent is mixed to get by sodium hydroxide solution and sodium carbonate liquor, the hydrogen-oxygen
Changing the ratio between the equivalent concentration of sodium solution and the equivalent concentration of the sodium carbonate liquor is 1:1.
It is also preferred that: the molar concentration of the sodium hydroxide solution is 4mol/L, mole of the sodium carbonate liquor
Concentration is 2mol/L.
The sodium ion equivalent concentration of both sodium hydroxide and sodium carbonate is all 4N/L in the preferred embodiment.Sodium after the two mixing
The equivalent concentration of ion is constant, and the simplicity for being conducive to control with the operation of entire production process is quick, under this molar concentration, hydrogen
Sodium hydroxide solution and sodium carbonate liquor volume ratio are 2:3, can not only save production cost, while avoiding sodium carbonate liquor to having
Machine extractant generates excessive carbon dioxide gas when being saponified cause organic phase to be not thorough with water phase layering, influences product
The phenomenon that purity and quality.
The present invention further discloses the application methods of the saponification agent of the rare earth organic extractant, comprising the following steps:
(1) aqueous sodium carbonate for being 2mol/L with molar concentration by the sodium hydrate aqueous solution that molar concentration is 4mol/L
The saponification agent is obtained for 2:3 mixing by volume, the saponification agent, and the sulfonation as organic phase are added into soap tank
Kerosene and organic extractant P507；
(2) mixed liquor that need to carry out extraction and separation is firstly added in the soap tank and carries out organic saponification, thereafter will
Mixed liquor after saponification carries out extraction grouping.
Preferably, the application method be applied to mixed chlorinated rare earth extraction with separate.
It is further preferred that the step (2) includes that successively the step (2) includes to described to the mixed liquor
Mixed liquor successively carries out the organic saponification of Nd/Sm, Nd/Sm grouping, the organic saponification of Ce/Pr, Ce/Pr grouping and the organic soap of La/Ce
Change, La/Ce separation process, respectively obtain Nd/Sm grouping object Sm Eu Gd concentrate product, Ce/Pr grouping object praseodymium neodymium product and
Single lanthanum, cerium product.
The another kind of the application method is further preferred are as follows: the mistake of organic saponification, the Nd/Sm grouping of the Nd/Sm
Journey are as follows: in the case where being slowly stirred, the flow that the organic phase is controlled in soap tank is 28 ~ 32L/min, the saponification agent
Flow be 1.54 ~ 1.76L/min, the flow of the mixed liquor is 24 ~ 30L/min, the first saponification efflux is obtained, by
One saponification efflux carries out thereafter Nd/Sm grouping in extraction tank, obtains Sm Eu Gd concentrate product and remaining second mixing
Feed liquid.
The saponification degree of organic extractant described in the above process is 0.2 ~ 0.24 N/L.
It is further preferred are as follows: the organic saponification of the Ce/Pr, Ce/Pr grouping process are as follows: in the feelings being slowly stirred
Under condition, the flow that the organic phase is controlled in soap tank is 100 ~ 120L/min, the flow of the saponification agent be 13.5 ~
16.2L/min, second mixed liquor flow be 24 ~ 30L/min, obtain the second saponification efflux, by second saponification flow
Liquid carries out thereafter Ce/Pr grouping in extraction tank out, obtains praseodymium neodymium product and remaining third mixed liquor.
The saponification degree of organic extractant described in the above process is 0.5 ~ 0.54 N/L.
It is further preferred are as follows: the organic saponification of the La/Ce, La/Ce separation process are as follows: in the feelings being slowly stirred
Under condition, the flow that the organic phase is controlled in soap tank is 60 ~ 70L/min, the flow of the saponification agent is 8.1 ~ 9.45L/
Min, the flow of the third mixed liquor are 12 ~ 15L/min, obtain third saponification efflux, by third saponification efflux its
It is separated in extraction tank afterwards, obtains single lanthanum chloride and cerium chloride product.
The saponification degree of organic extractant described in the above process is 0.5 ~ 0.54 N/L.
The invention has the following advantages:
(1) it significantly reduces production cost and extracts the life of single REO rare earth if directly using sodium hydroxide as saponification agent
Producing cost needs 3000 ~ 4000 yuan, and production cost can be down to 1500 ~ 2500 yuan using the present invention；
(2) in extraction process basic no third phase formation, in extraction process, if producing third in extraction system
Organic moiety in third phase can be separated in the case where slow agitation with other sundries, be made by phase, the sodium carbonate in saponification agent
Organic moiety returns in organic phase, and system is made to remain stable two-phase, to improve the extracting power of organic extractant, show
Writing reduces the dosage of organic extractant, if the amount sodium hydroxide of substances such as directly using as saponification agent one ton of REO of separation, need
5 ~ 10kg of organic extractant, 6 ~ 8kg of sulfonated kerosene is lost, only needs to consume same 2 ~ 3kg of organic extractant using the present invention,
3 ~ 4kg of sulfonated kerosene can save production cost 30 ~ 500,000 yuan if enterprise need to separate 5000 tons of REO rare earths for 1 year；
(3) sodium carbonate liquor also has other than having pointed by such as above-mentioned (2) point to the palingenesis of organic phase
Wash the function of organic phase, not only in extraction process in system basic no third phase formation, while organic phase is in extraction process
In maintain higher quality, keep finally obtained rare-earth products purity higher, such as directly use sodium hydroxide as saponification agent
When, the lanthanum oxide purity extracted is 99.95%, and cerium oxide product purity is 99.9%, after the present invention, similarly
Under organic extractant, lanthanum oxide purity is promoted to 99.995%, and cerium oxide product purity is promoted to 99.99%；
(4) incorporation time automatically prolongs, and product quality is made to get a promotion, because extracting power of the invention is higher, when extraction
Smaller organic phase flow may be selected, such as directly use sodium hydroxide as saponification agent, in same saponification degree, same REO
Fractional dose, etc. in the case where the saponification agent of quality, the flow of organic phase is 120 ~ 140L/min, uses flow organic after the present invention
For 100 ~ 120L/min, raw material extends 15 ~ 30s in the mixing indoor average time of extraction tank washing section, further improves
The purity of product after extraction.
Figure of description
Fig. 1 is a kind of process flow chart of preferred application method of saponification agent of the invention.
Specific embodiment
The present invention is further illustrated combined with specific embodiments below.
Embodiment 1
(1) the aqueous sodium carbonate 6m3 that molar concentration is 2mol/L is added in the first agitator tank, is then filtered,
The sodium hydroxide 4m3 that molar concentration is 4mol/L is added in the second agitator tank, stands, filtered sodium carbonate liquor is squeezed into
It in second agitator tank, is mixed with prepared sodium hydroxide solution in advance, after mixing evenly as saponification agent, it is standby to squeeze into head tank
With；In addition prepare organic phase sulfonated kerosene and organic extractant P507；
(2) mixture of the saponification agent, organic phase, organic extractant and mixed chlorinated rare earth is added in soap tank
Liquid, in the case where being slowly stirred, the flow for controlling the organic phase is the saponification degree of 28 ~ 32L/min, the organic extractant
Flow for 0.2 ~ 0.24 N/L, the saponification agent is 1.54 ~ 1.76 L/min, the flow of the mixed liquor is 24 ~ 30L/
Min, obtained efflux are the first saponification efflux, and the first saponification efflux is carried out thereafter Nd/Sm extraction in extraction tank
Grouping, obtains Sm Eu Gd concentrate product and remaining second mixed liquor；
(3) the second mixed liquor, saponification agent, organic phase, organic extractant are added to saponification in the case where being slowly stirred
In slot, the flow for controlling the organic phase is 100 ~ 120L/min, the saponification degree of the organic extractant be 0.5 ~ 0.54 N/L,
The flow of the saponification agent is 13.5 ~ 16.2 L/min, the flow of second mixed liquor is 24 ~ 30L/min, obtained stream
Liquid is the second saponification efflux out, and the second saponification efflux is carried out thereafter Ce/Pr extraction grouping in extraction tank, obtains praseodymium neodymium
Product and remaining third mixed liquor；
(4) third mixed liquor, saponification agent, organic phase, organic extractant are added to saponification in the case where being slowly stirred
In slot, control the flow of the organic phase for the saponification degree of 60 ~ 70L/min, the organic extractant be 0.5 ~ 0.54 N/L, institute
The flow for stating saponification agent is 8.1 ~ 9.45L/min, and the flow of the third mixed liquor is 12 ~ 15L/min, obtained efflux
It is saponified efflux for third, third saponification efflux is subjected to La/Ce extraction and separation in extraction tank, obtains single lanthanum chloride
And cerium chloride product.
Embodiment 2
(1) the aqueous sodium carbonate 6m3 that molar concentration is 2mol/L is added in the first agitator tank, is then filtered,
The sodium hydroxide 4m3 that molar concentration is 4mol/L is added in the second agitator tank, stands, filtered sodium carbonate liquor is squeezed into
It in second agitator tank, is mixed with prepared sodium hydroxide solution in advance, after mixing evenly as saponification agent, it is standby to squeeze into head tank
With；In addition prepare organic phase sulfonated kerosene and organic extractant P507；
(2) mixture of the saponification agent, organic phase, organic extractant and mixed chlorinated rare earth is added in soap tank
Liquid, in the case where being slowly stirred, the flow for controlling the organic phase is the saponification degree of 28 ~ 32L/min, the organic extractant
Flow for 0.2 ~ 0.24 N/L, the saponification agent is 1.54 ~ 1.76 L/min, the flow of the mixed liquor is 24 ~ 30L/
Min, obtained efflux are the first saponification efflux, and the first saponification efflux is carried out thereafter Nd/Sm extraction in extraction tank
Grouping, obtains Sm Eu Gd concentrate product and remaining second mixed liquor；
(3) the second mixed liquor, saponification agent, organic phase, organic extractant are added to saponification in the case where being slowly stirred
In slot, the saponification degree for controlling the organic extractant is 0.54 N/L, the flow of the saponification agent be 13.5 ~ 16.2 L/min,
The flow of second mixed liquor is 24 ~ 30L/min, and obtained efflux is the second saponification efflux, and the second saponification is flowed
Liquid carries out thereafter Ce/Pr extraction grouping in extraction tank out, obtains praseodymium neodymium product and remaining third mixed liquor.
In step (3) because control organic extractant saponification degree be 0.54 N/L, the flow of saponification agent is 13.5 ~ 16.2
L/min, the second mixed liquor flow be 24 ~ 30L/min, the average flow rate of organic phase is 115L/min when saponification；
Using same organic phase, organic extractant and identical second mixed liquor for waiting quality, made with sodium hydroxide
It is compared for saponification agent, under similarly saponification agent flux, the second mixed liquor flow and saponification degree, the mean flow of organic phase
Amount is 125L/min；
When above-mentioned comparative illustration carries out saponifiable extraction using sodium carbonate-sodium hydroxide mixing saponification agent, same fractional dose
Under saponification degree, the flow of organic phase is reduced, and similarly extracts series, and the mixed time increases, and improves organically extraction energy
Power；To improve the purity of product.
On the basis of using sodium hydroxide as saponification agent completely, the present embodiment is calculated for 300 days by annual work, can be saved
About about 300,000 yuan of production cost.
Claims (1)
1. a kind of application method of the saponification agent of rare earth organic extractant, it is characterised in that: the saponification agent by sodium hydroxide and
Sodium carbonate composition, is mixed to get, the equivalent concentration of the sodium hydroxide solution by sodium hydroxide solution and sodium carbonate liquor
It is 1:1 with the ratio between the equivalent concentration of the sodium carbonate liquor, the molar concentration of the sodium hydroxide solution is 4mol/L, the carbon
The molar concentration of acid sodium solution be 2mol/L, the saponification agent be applied to mixed chlorinated rare earth extraction with separate, application
Process the following steps are included:
(1) by molar concentration be 4mol/L sodium hydrate aqueous solution and molar concentration be 2mol/L aqueous sodium carbonate by body
The saponification agent, and the sulfonated kerosene as organic phase are added into soap tank than obtaining the saponification agent for 2:3 mixing for product
With organic extractant P507；
(2) mixed liquor that need to carry out extraction and separation is firstly added the soap tank and successively carries out the organic saponification of Nd/Sm, Nd/
Sm grouping, the organic saponification of Ce/Pr, Ce/Pr grouping and the organic saponification of La/Ce, La/Ce separation respectively obtain Nd/Sm grouping object samarium
Europium gadolinium enriched substance product, Ce/Pr grouping object praseodymium neodymium product and single lanthanum, cerium product；
The wherein process of organic saponification of the Nd/Sm, Nd/Sm grouping are as follows: in the case where being slowly stirred, in soap tank internal control
The flow for making the organic phase is 28 ~ 32L/min, the flow of the saponification agent is 1.54 ~ 1.76L/min, the mixed liquor
Flow be 24 ~ 30L/min, obtain the first saponification efflux, by first saponification efflux Nd/Sm is carried out in extraction tank thereafter
Grouping, obtains Sm Eu Gd concentrate product and remaining second mixed liquor；
The process of the organic saponification of the Ce/Pr, Ce/Pr grouping are as follows: in the case where being slowly stirred, in soap tank described in control
The flow of organic phase is 100 ~ 120L/min, the flow of the saponification agent is 13.5 ~ 16.2L/min, second mixed liquor
Flow be 24 ~ 30L/min, obtain the second saponification efflux, by second saponification efflux Ce/Pr is carried out in extraction tank thereafter
Grouping, obtains praseodymium neodymium product and remaining third mixed liquor；
The process of the organic saponification of the La/Ce, La/Ce separation are as follows: in the case where being slowly stirred, in soap tank described in control
The flow of organic phase is 60 ~ 70L/min, the flow of the saponification agent is 8.1 ~ 9.45L/min, the stream of the third mixed liquor
Amount is 12 ~ 15L/min, obtains third saponification efflux, and third saponification efflux is separated in extraction tank thereafter, is obtained
Single lanthanum chloride and cerium chloride product.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1394972A (en) * | 2002-07-09 | 2003-02-05 | 中国科学院长春应用化学研究所 | Process for separating high-purity yttrium by using oxyl substituted acetic acid as extracting agent |
| CN1455009A (en) * | 2003-05-17 | 2003-11-12 | 包头稀土研究院 | Preparation of rare earth chloride from long-chain fatty acid extracting transformation and back-extraction process thereof |
| CN102071316A (en) * | 2010-11-25 | 2011-05-25 | 广东富远稀土新材料股份有限公司 | Three-component separation method of multi-component rare earth |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1394972A (en) * | 2002-07-09 | 2003-02-05 | 中国科学院长春应用化学研究所 | Process for separating high-purity yttrium by using oxyl substituted acetic acid as extracting agent |
| CN1455009A (en) * | 2003-05-17 | 2003-11-12 | 包头稀土研究院 | Preparation of rare earth chloride from long-chain fatty acid extracting transformation and back-extraction process thereof |
| CN102071316A (en) * | 2010-11-25 | 2011-05-25 | 广东富远稀土新材料股份有限公司 | Three-component separation method of multi-component rare earth |
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