CN104498714A

CN104498714A - Method for removing iron, aluminum, calcium and titanium impurities from scandium-containing solution

Info

Publication number: CN104498714A
Application number: CN201410809499.0A
Authority: CN
Inventors: 李青刚; 李兆洋; 孙盼; 张贵清; 肖连生; 曹佐英
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2014-12-22
Filing date: 2014-12-22
Publication date: 2015-04-08
Anticipated expiration: 2034-12-22
Also published as: CN104498714B

Abstract

The invention discloses a method for removing iron, aluminum, calcium and titanium impurities from a scandium-containing solution. The method comprises the following steps: (1) reducing, namely adding a reducing agent into the scandium-containing solution for reducing Fe (III) into Fe (II); (2) adding a complexing agent into the scandium-containing solution reduced in the step (1) for complexing Sc (III); (3) adding alkali into the complexed scandium-containing solution, and regulating the pH value of the solution to 1-7; and (4) mixing the scandium-containing solution with strong-acidity ion exchange resin, or enabling the scandium-containing solution to flow through an exchange column filled with the strong-acidity ion exchange resin, and adsorbing impurity ions to obtain a pure scandium solution. The method disclosed by the invention can be used for effectively and deeply removing impurities such as iron, aluminum and calcium from the scandium-containing solution through an ion exchange method, and also can be used for removing part of impurities such as titanium, zirconium, magnesium and manganese, so that an effective impurity removal method is provided for preparing high-purity scandium.

Description

The method of iron, aluminium, calcium, titanium impurity is removed from containing separation scandium solution

Technical field

The invention belongs to chemical metallurgy field, be specifically related to one and go deimpurity method from containing scandium solution.

Background technology

The nineties rises, and many countries, comprise China, has started production and the research boom of scandium.Russia has developed many kinds of applicable industries Mo-bearing granitoid, obtains application in many new and high technology departments.In western countries, scandium application in the supply achieves huge advance, and scandium sodium vapor lamp obtains increasingly extensive application.At present, scandium develops new advancement is the research and development reducing costs and comprise the overall application of switching from manufacturing military products to goods for civilian use energetically.

Occurring in nature reaches more than 800 kinds containing the mineral of scandium, nearly all can find the trace of scandium in the by product in granite pegmatite type ore deposit.But Scium trioxide grade is greater than the ore deposit of 0.05% for several very few.The high yield mineral of China scandium aboundresources, particularly China, if bauxite and phosphorite deposit, south China Porphyry Type and quartz-vein type tungsten deposit, south China rare-earth mineral, Inner Mongol Bayan Obo Rare-Earth Iron Mine bed and v-ti magnetite mineral deposit, Sichuan etc. are all containing scandium.So the extraction of scandium is all for raw material substantially with the acidic hydrolysis waste water in the leached mud in the red mud in aluminum oxide industry, tungsten metallurgy, Production By Sulfuric Acid Process titanium white process and the flue dust in titanium slag chlorination process.

Because the substances content such as Fe, Al, Ti in these raw materials are very high, be present in Scium trioxide or containing in scandium solution with Impure forms preparing in Scium trioxide process them, thus affect the purity of product scadium compound.

Extraction process is mainly at present from scadium compound or containing the method being separated these impurity scandium solution, invention as the patent No. 201310237363.2 P204 extracting scandium, although the extracting power of P204 to scandium is extremely strong, but selectivity is very poor, most of impurity element also by extraction, makes removal of impurities operation become more complicated, extracting and separating progression is huge, final Scium trioxide purity is only 90%-95%, and along with the high trade effluent output of COD content, tooling cost is higher.

Also have and adopt the precipitator method to go deimpurity technology, filter cake is calcined by after repeatedly dissolving-Filtration-Precipitation-rinsing-filtration by the invention being 201110186520.2 as number of patent application, the high purity scandium of 99.99% can be obtained, effective separating impurity, but it is larger that repeatedly precipitation-dissolve-filtration makes scandium lose, the yield of scandium is low, and produces a large amount of waste water.

Summary of the invention

For this area weak point, the present invention is intended to provide a kind of method of effectively going out impurity iron from thick Scium trioxide, and by ion-exchange techniques, the clearance of iron can reach 98%, and the clearance of aluminium reaches 99.9%, and the clearance of calcium is close to 99%.The method is simple to operate, and cost is low, effective.

The technical scheme realizing the object of the invention is:

Remove a method for iron, aluminium, calcium, titanium impurity from containing separation scandium solution, comprise step:

(1) reduce: determine, containing Fe (III) content in scandium solution, to add reductive agent to containing in scandium solution, Fe (III) is reduced to Fe (II); Described reductive agent is one or more in xitix, iron powder, Sulfothiorine, hydrazine hydrate, ammonium sulfide, and reductive agent addition is 1 ~ 4 times that Fe (III) is reduced to the required theoretical amount of Fe (II).

(2) complexing: add complexing agent complexes Sc (III) to containing in scandium solution after step (1) reduction;

(3) PH is regulated: add alkali to containing in scandium solution after complexing, the pH value of regulator solution is to 1-7;

(4) impurity such as resin absorption iron, aluminium, calcium, titanium: through reduction, the mixing with strong-acid ion exchange resin containing scandium solution of complexing and adjust ph, or make it flow through to be equipped with the exchange column of storng-acid cation exchange resin, the impurity such as iron, titanium, calcium, titanium by resin absorption, thus obtain pure scandium solution.

In technical solution of the present invention,

Fe (III) in solution is reduced to Fe (II) by reduction process; Add appropriate complexing agent with complexing Sc (III) to containing in scandium solution after reduction, change positively charged ion scandium into complex anion, thus avoid resin to the absorption of scandium.Have precipitation to produce if regulated in PH process, need to filter, filtrate carries out next step operation.In the impurity processes such as ion exchange resin absorption iron, aluminium, calcium, titanium, the impurity that most iron, aluminium, calcium and part magnesium, manganese, zirconium etc. exist with positively charged ion form is adsorbed by storng-acid cation exchange resin, and scandium is because exist in solution with complex anion, thus obtain pure scandium solution.

Wherein, described is containing Sc (III), Fe (III), Fe (II), Ca containing scandium solution ²⁺, Mg ²⁺, Al ³⁺, Ti ⁴⁺in the hydrochloric acid soln of one or more ions, sulphuric acid soln, salpeter solution or its mixture.

Particularly, described containing the scandium solution intermediate product that is scandium-containing mineral metallurgy or with solution like its constituent class, the acidic hydrolysis waste water in the leached mud in such as, red mud in aluminum oxide industry, tungsten metallurgy, Production By Sulfuric Acid Process titanium white process and the flue dust in titanium slag chlorination process are raw material; Or the solution approximate with described metallurgical process gained leach liquor composition, wherein containing Sc (III) 0.1-10.86g/L, Fe (III) 0.1-6.0g/L, Al 0.1-2.0g/L, Ca 0.1-1.0g/L, Ti 5-20g/L.

Preferably, reductive agent described in described step (1) is one or more in xitix, Sulfothiorine, hydrazine hydrate, ammonium sulfide, and addition is 1 ~ 1.5 times of complexing scandium theoretical amount.

Wherein, in described step (2), complexing agent used is one or more in EDTA (ethylenediamine tetraacetic acid (EDTA)), NTA (nitrilotriacetic acid(NTA)), HEDTA (hydroxyethyl disodium salt), DTPA, DCTA, lactic acid, and addition is 1 ~ 2 times that theoretical complexing Sc (III) is measured.

Preferably, in described step (3), the alkali of adjustment pH is one or more in sodium hydroxide, sodium carbonate, ammoniacal liquor, pH regulator to 2 ~ 4.

Wherein, in described step (4) resin be strongly acidic styrene type cation exchange resin, be selected from wide-aperture D001, D003, gel-type 001 × 7 (732), 001 × 3,001 × 4 resin.

When carrying out ion-exchange with resin filling ion exchange column, can according to determining column volume, loading capacity and duration of contact containing scandium solution-treated amount and flow velocity.Such as, volume ratio when containing scandium solution and storng-acid cation exchange resin mixing and absorption in step (4) is 10-50:1; During containing scandium solution stream through being equipped with the exchange column of 20ml storng-acid cation exchange resin, solution flow rate is 10-30mL/h.

Further, the resin concentration of having adsorbed in described step (4) after impurity be the sulfuric acid of 1 ~ 3mol/L, hydrochloric acid, nitric acid or its mixing solutions as strippant, the resin after desorb can return absorption and use.

Beneficial effect of the present invention is:

1. adopt ion-exchange method effectively from Scium trioxide the degree of depth eliminate the impurity such as impurity iron, aluminium, calcium;

2. the inventive method can also the simultaneously impurity such as remove portion titanium, zirconium, magnesium, manganese, and the preparation for high purity scandium provides effective impurity-removing method.

3. the inventive method scandium rate of recovery is high, and in whole process, scandium loss seldom.

4. the inventive method is simple to operate, and cost is lower.

Accompanying drawing explanation

Fig. 1 is the process flow sheet of the inventive method;

Embodiment

Now with following most preferred embodiment, the present invention is described, but is not used for limiting the scope of the invention.

The feed liquid of embodiment 1-6 is prepared with thick Scium trioxide.

Embodiment 1: different from separating effect in scandium solution system

(1) prepare Scium trichloride solution respectively, the composition existed with hydrochloride form in solution is: Sc (III) 0.82g/L, Fe (III) 0.65g/L, Al 0.68g/L, Ca 0.51g/L; Scandium sulfate solution, the composition existed with sulphate form in solution is: Sc (III) 0.86g/L, Fe (III) 0.75g/L, Al 0.65g/L, Ca 0.55g/L; Scium trinitrate solution, the composition existed with nitrate salts in solution is: Sc (III) 0.88g/L, Fe (III) 0.68g/L, Al 0.60g/L, Ca 0.50g/L;

(2) adding 1.05 times of theoretical amount xitix reduction Fe (III) is Fe (II);

(3) 2.0 times of theoretical amount EDTA complexings Sc (III) are added;

(4) three kinds of feed liquid PH are regulated to be 3.0 with the sodium hydroxide solution of 4mol/L;

(5) after graduated cylinder measures 100ml feed liquid and 10ml process, the D001 macroporous resin of (process be h type resin by ion exchange resin conversion) is placed in 250ml Erlenmeyer flask, concussion absorption under room temperature.Absorption result is in table 1.

The adsorption rate of scandium and iron, aluminium, calcium under the different pH value of table 1

Solution system	Scium trichloride solution	Scandium sulfate solution	Scium trinitrate solution
				Fe adsorption rate	91.2％	90.3％	89.3％
Al adsorption rate	93.5％	94.5％	94.1％
				Ca adsorption rate	92.6％	91.6％	93.1％
Sc adsorption rate	1.4％	1.7％	1.6％

Embodiment 2: different cationic exchange resin adsorption separating effect

(1) prepare the same Scium trichloride solution of six parts of compositions, the composition existed with hydrochloride form in solution is: Sc (III) 0.82g/L, Fe (III) 0.65g/L, Al 0.68g/L, Ca 0.51g/L; .

(2) adding 1.5 times of theoretical amount xitix reduction Fe (III) is Fe (II).

(3) 1.1 times of theoretical amount EDTA complexing Sc are added.

(4) with the ammoniacal liquor of 26%, the pH value of solution is adjusted to 3.0.。

(5) graduated cylinder measures 100ml solution and is placed in six 250ml Erlenmeyer flasks, add after 10ml process 001 × 3 respectively, 001 × 4,001 × 7, D001, D003 and D115 resin, at room temperature shake absorption.

Absorption result is in table 2.

The adsorption rate of the resin absorption scandium of the different trade mark of table 2 and iron, aluminium, calcium

Resin

001×3

001×4

001×7

D001

D003

D115

Fe adsorption rate

94.4％

93.6％

93.2％

90.1％

88.8％

55.8％

Al adsorption rate

96.9％

97.1％

96.5％

92.8％

95.0％

56.1％

Ca adsorption rate

96.0％

95.5％

95.6％

93.3％

95.2％

59.6％

Sc adsorption rate

3.8％

2.1％

1.6％

1.4％

1.5％

3.3％

Separating effect under embodiment 3 different pH condition

(1) prepare the same Scium trichloride solution of six parts of compositions, the composition existed with hydrochloride form in solution is: Sc (III) 1.55g/L, Fe (III) 0.25g/L, Al 0.38g/L, Ca 0.46g/L, Ca 0.205g/l; .

(2) add 1.5 times of theoretical amount xitix and Fe (III) is reduced to Fe (II);

(3) 1.5 times of theoretical amount EDTA complexing Sc are added;

(4) PH of six parts of solution is regulated to be respectively 0,1.0,2.0,3.0,4.0,5.0 with the ammoniacal liquor of 26%;

(5) the D001 resin after graduated cylinder measures 100ml feed liquid and 10ml process is placed in 250ml Erlenmeyer flask, at room temperature shakes absorption.

The results are shown in Table 3.

The adsorption rate of scandium and iron, aluminium, calcium under the different pH value of table 3

PH

0

1.0

2.0

3.0

4.0

5.0

Fe adsorption rate

45.8％

90.2％

92.5％

93.6％

94.8％

94.5％

Al adsorption rate

36.8％

93.5％

96.0％

96.1％

96.6％

97.8％

Ca adsorption rate

22.1％

92.4％

94.8％

95.7％

96.6％

96.3％

Ti adsorption rate

28.4％

88.4％

89.2％

94.8％

95.1％

96.2％

Sc adsorption rate

0.4％

1.3％

1.6％

2.1％

2.8％

The separating effect of scandium and impurity when the different reductive agent of embodiment 4 and consumption

(1) prepare the same Scium trichloride solution of seven parts of compositions, the composition existed with hydrochloride form in solution is: Sc (III) 0.82g/L, Fe (III) 0.65g/L, Al 0.68g/L, Ca 0.51g/L;

(2) ferric iron back is ferrous iron by the reductive agent adding different sorts and quality.

(3) the EDTA complexing scandium of 1.5 times of theoretical amount is added;

(4) feed liquid PH is regulated to be 3.0 with sodium hydroxide solution;

(5) resin 001 × 7 after graduated cylinder measures 100ml feed liquid and 10ml process is placed in 250ml Erlenmeyer flask, at room temperature shakes absorption;

Result show, 001 × 7 resin to Fe, Al, Ca and Sc adsorption rate as table 4.

The adsorption rate (unit: theoretical amount multiple) of scandium and iron, aluminium, calcium under table 4 different sorts and quality

Embodiment 5: the separating effect of scandium and impurity during different complexing agent complexes

(1) prepare the same Scium trichloride solution of six parts of compositions, the composition existed with hydrochloride form in solution is: Sc (III) 0.5175g/L, Fe (III) 0.636g/L, Al 0.68g/L, Ca 0.51g/L;

(3) the different complexing agent complexes scandium of 1 times of theoretical amount is added;

(4) feed liquid PH is regulated to be 3.0 with sodium hydroxide solution;

(5) 001 × 7 resin after graduated cylinder measures 100ml feed liquid and 10ml process is placed in 250ml Erlenmeyer flask, at room temperature shakes absorption.

The results are shown in Table 5.

The adsorption rate of scandium and iron, aluminium, calcium under the different complexing agent complexes condition of table 5

Complexing agent

EDTA

HEDTA

DCTA

DTPA

NTA

Lactic acid

Fe adsorption rate

93.2％

92.8％

93.3％

93.8％

91.4％

Al adsorption rate

96.5％

96.6％

97.0％

97.5％

96.0％

92.6％

Ca adsorption rate

95.6％

95.1％

96.8％

94.2％

95.5％

92.8％

Sc adsorption rate

4.5％

4.8％

5.5％

6.6％

6.5％

12.8％

Embodiment 6: exchange column adsorption experiment

(1) feed liquid: Scium trichloride solution, in solution with hydrochloride form exist composition for Sc (III) 10.86g/L, Fe (III)+Fe (II) 0.403g/L, Al 0.51g/L, Ca 0.55g/L, Ti 0.60g/L, Mn 0.82g/L, Zr 0.34g/L.

(2) xitix adding the theoretical amount 1.2 times Fe (III) being reduced to Fe (II) reduces.

(3) add 1.2 times of complexing scandium theoretical amount EDTA and carry out complexing.

(4) feed liquid PH is regulated to be 3.0 with 4mol/L sodium hydroxide solution.

(5) above-mentioned feed liquid 300ml flows through the glass exchange column that 20ml 001 × 7 resin is housed, feed velocity 20ml/h, room temperature.

(6) after absorption, carry out drip washing 3 hours, then use 2mol/L hydrochloric acid soln vapor with pure water with the flow velocity coupled columns internal burden resin of 10ml/h, controlling stripping liquid flow velocity is 10ml/h, desorb 3 hours.

Flow process is shown in Fig. 1.Experimental result is shown in Table 6.

Table 6 exchange column Adsorption iron, aluminium, should, the impurity effect such as titanium

Embodiment 7: exchange column adsorbs

(1) feed liquid: the chlorination flue dust in titanium smelting process, use 2mol/L dissolve with hydrochloric acid solution, in solution with hydrochloride form exist composition for Sc (III) 2.02g/L, Fe (III)+Fe (II) 5.12g/L, Al 1.35g/L, Ca 0.45g/L, Ti 15.30g/L, Mn 2.24g/L, Zr 1.15g/L.

(2) add 1.2 times of theoretical amount the xitix that Fe (III) is reduced to Fe (II) is reduced.

(3) the theoretical amount EDTA adding 1.2 times of complexing scandiums carries out complexing.

Experimental result is shown in Table 7.

Table 7 exchange column Adsorption iron, aluminium, should, the impurity effect such as titanium

Above embodiment is only be described the preferred embodiment of the present invention; not scope of the present invention is limited; under not departing from the present invention and designing the prerequisite of spirit; the various modification that the common engineering technical personnel in this area make technical scheme of the present invention and improvement, all should fall in protection domain that claims of the present invention determine.

Claims

1. remove a method for iron, aluminium, calcium, titanium impurity from containing separation scandium solution, it is characterized in that, comprise step:

(1) reduce: determine, containing Fe (III) content in scandium solution, to add reductive agent to containing in scandium solution, Fe (III) is reduced to Fe (II); Described reductive agent is one or more in xitix, iron powder, Sulfothiorine, hydrazine hydrate, ammonium sulfate, and reductive agent addition is 1 ~ 4 times that Fe (III) is reduced to the required theoretical amount of Fe (II);

(4) impurity such as resin absorption iron, aluminium, calcium, titanium: through reduction, the mixing with strong-acid ion exchange resin containing scandium solution of complexing and adjust ph, or the exchange column making it flow through to be equipped with storng-acid cation exchange resin, obtain pure scandium solution.

2. method according to claim 1, is characterized in that, described is containing Sc (III), Fe (III), Fe (II), Ca containing scandium solution ²⁺, Mg ²⁺, Al ³⁺, Ti ⁴⁺in the hydrochloric acid soln of one or more ions, sulphuric acid soln, salpeter solution or its mixture.

3. method according to claim 1, is characterized in that, reductive agent described in described step (1) is one or more in xitix, Sulfothiorine, hydrazine hydrate, ammonium sulfide, addition 1 ~ 1.5 times of theoretical amount needed for complexing scandium.

4. method according to claim 1, it is characterized in that, in described step (2), complexing agent used is one or more in EDTA (ethylenediamine tetraacetic acid (EDTA)), NTA (nitrilotriacetic acid(NTA)), HEDTA (hydroxyethyl disodium salt), DTPA, DCTA, lactic acid, and addition is 1 ~ 2 times that theoretical complexing Sc (III) is measured.

5. method according to claim 1, is characterized in that, in described step (3), the alkali of adjustment pH is one or more in sodium hydroxide, sodium carbonate, ammoniacal liquor, pH regulator to 2 ~ 4.

6. method according to claim 1, it is characterized in that, in described step (4) resin be strongly acidic styrene type cation exchange resin, be selected from wide-aperture D001, D003, gel-type 001 × 7 (732), 001 × 3,001 × 4 resin.

7. method according to claim 1, it is characterized in that, the resin concentration of having adsorbed in described step (4) after impurity be the sulfuric acid of 1 ~ 3mol/L, hydrochloric acid, nitric acid or its mixing solutions as strippant, the resin after desorb can return absorption and use.