presented by Şerif kaya prof. dr. yavuz a....

Presented by Şerif KAYA

Supervisor: Prof. Dr. Yavuz A. TOPKAYA, Middle East Technical UniversityMetallurgical & Materials Engineering Dept. Ankara/Turkey

with the support of Dr. Carsten Dittrich, MEAB Chemie Technik GmbH and META Nikel-Kobalt A.Ş.

Leuven, 20155-7 October

Bauxite Residue Valorisation and Best Practices Conference, Leuven, 5-7 October

Outline

3. Previous Studies and Findings

2. General Overview of MHP Process

1. General Information about Scandium

4. Precipitation Experiments and Behaviour of Scandium

5. Current and Future Studies

7. References

6. Discussion & Conclusion

8. Questions & Answers

2Leuven, 20155-7 October

3

Importance of Scandium

• Scandium has been obtained from various ores, tailings and residues of previously exploited mines as a by-product up to now. (e.g.: U, Sn, Ta, Ti, W, etc.)

• The main application areas; high strength and light-weight Al-Sc alloys, lighting, electronics, laser research and solid oxide fuel cells.

• However, the supply of Sc is very scarce (5-12 t/a) and price is very high e.g. 99.9% Sc2O3 2000-3000$, [1]- Riggall 2015.

• The presence of ~50-100 ppm Sc in lateritic Ni-Co deposits seems to be a very prominent source for the extraction of Sc together with Ni & Co.


Conventional MHP Process (pH controlled precipitation)

How to recover Sc from a MHP Circuit?


Precipitation Behaviour of Ions wrt pH at 25 °C

5

Fe(III) > Al(III) > Sc(III) > Cr(III) > Cu(II) > Fe(II) > Zn(II) > Ni(II) > Co(II) > Mn(II)

Sc


Findings presented in ERES 2014 Conference

6

Parameters Studied for Sivrihisar Lateritic Nickel Ore

• Sulphuric Acid to Ore Ratio:(160, 180, 200, 220, 240, 260, 270, 285, 300, 325, 350 kg/ton dry ore)

• Temperature:(245, 255, 265, 275 °C)

• Particle Size:(-850, -425, and -74 µm)

• Duration:(30 min., 60 min., 90 min., 120 min., 360 min.)

Optimum Leaching Parameters: 260 kg acid/ton dry ore, 255 °C, -850 µm, 60 min.

[2]- Kaya Ş, Topkaya Y.A., ‘High Pressure Acid Leaching of a Nickel Laterite Ore to Extract Scandium’, 1st European Rare Earth Resources Conference, Milos, Greece, 2014.

Preparation of the Synthetic Solution

7

• Composition of the optimum PLS and Synthetic Leach Solution

Element PLS Composition (mg/L) Synthetic Solution (mg/L) Reagent

Nickel 5502 5827 Ni(II) Sulfate Hexahydrate

Cobalt 321 371 Co(II) Sulfate Heptahydrate

Scandium 34 30 Sc(III) Sulfate Octahydrate

Iron 1688 1814 Fe(III) Sulfate Hydrate

Aluminum 3985 4317 Al(III) Sulfate (18.H2O)

Chromium 342 150 Cr(III) Sulfate Hydrate

Manganese 2110 2056 Mn(II) Sulfate Monohydrate

Magnesium 1285 1369 Mg(II) Sulfate Heptahydrate

Copper 28 29 Co(II) Sulfate Pentahydrate

Zinc 73 74 Zn(II) Sulfate Heptahydrate


8

Experimental Set-up


MicropipettepH Meter

CaCO3 Slurry

Hot Plate & Magnetic Stirrer

pH Probe

Contact Thermometer

Condenser

CaCO3 Addition

9

Fe-I Removal ExperimentsFe-I Removal Experiments (at 90 °C, 120 minutes)Fe-I Removal Experiments (at 90 °C, 120 minutes)

• Aim is to obtain max. Fe ppt. with min. Ni, Co, Sc ppt losses.

• After the determination of optimum pH, a series of exp. to prepare a stock solution for Fe-II Removal Step was carried out.

Exp-1 Exp-2 Exp-3 Exp-4 Exp-5 Exp-6 Exp-7 Exp-8 Exp-9

pH 2.00 pH 2.50 pH 2.75 pH 3.00 pH 3.25 pH 3.50 pH 4.00 pH 4.50 pH 5.00


10

Ni

Co

Sc

Fe

Mn

AlCrCu

Zn

0

20

40

60

80

100

1,75 2,00 2,25 2,50 2,75 3,00 3,25 3,50 3,75 4,00 4,25 4,50 4,75 5,00

% P

reci

pita

tion

pH

Fe- I Precipitation Results

Fe-I Removal Results


Element PLS (mg/L)

PLS after ppt. @ pH

2.75(mg/L)

Ni 5827 4650

Co 371 268

Sc 30 23

Fe 1814 227

Al 4317 3599

Cr 150 98

Mn 2056 1905

Mg 1369 1211

Cu 29 28

Zn 74 67


Fe-II Removal Experiments

Fe-II Removal Experiments (at 70 °C, 180 minutes)

• Aim is to precipitate all of the remaining Fe and Sc with min. Ni and Co ppt losses.

• After the determination of optimum pH, a series of exp. was carried out to prepare a stock of Fe-II precipitate for Releaching Step.

Exp-1 Exp-2 Exp-3 Exp-4 Exp-5

pH 4.00 pH 4.25 pH 4.50 pH 4.75 pH 5.00


Ni Ni

Ni

Co

Co

Sc

Sc ScSc Sc

Fe

Fe

Fe

Fe Fe

MnMn Mn Mn

Mn

AlAl Al

Al Al

Cr

Cr Cr CrCr

Cu

Cu

Cu

Cu Cu

Zn

Zn

Zn

Zn

0

20

40

60

80

100

3,75 4,00 4,25 4,50 4,75 5,00

% P

reci

pita

tion

pH

Fe- II Precipitation Results

Fe-II Removal ResultsElement Initial

PLS (mg/L)

PLS after ppt.

@ pH 4.75(mg/L)

Ni 4650 2819

Co 268 241

Sc 23 0

Fe 227 2

Al 3599 4

Cr 98 <5

Mn 1905 1509

Mg 1211 -

Cu 28 <5

Zn 67 41


After Fe-II purification a precipitate containing 703 g/ton Sc was obtained.

Initially the ROM contained 106 g/ton Sc. Experiments ac

Exp-1 Exp-2 Exp-3 Exp-4

25 gpl H2SO4 50 gpl H2SO4 75 gpl H2SO4 100 gpl H2SO4

Releaching Exp. of Sc enriched Fe-II Precipitate

Element Solid Comp.(g/ton)

Nickel 4010

Cobalt 36

Scandium 703

Iron 3100

Aluminum 11.6 %

Chromium 1446

Manganese 29

Calcium 14.6 %

Copper 504

Zinc 368

Composition of the solid residue before releaching


Releaching Results of Sc enriched Fe-II Precipitate

Exp. % Sc Extracted

Ni

(mg/L)

Co

(mg/L)

Sc

(mg/L)

Fe

(mg/L)

Al

(mg/L)

Cr

(mg/L)

Mn

(mg/L)

Cu

(mg/L)

Zn

(mg/L)

25 g/L

H2SO4

42.5 373 4.6 72 220 8180 158 3.8 50 36

50 g/L

H2SO4

72.5 664 6.8 121 507 15925 344 4.4 88 56

75 g/L

H2SO4

82.4 776 7.6 136 617 18683 423 4.8 102 65

100 g/L

H2SO4

91.9 928 8.7 153 659 18848 529 4.6 102 64


Summary of Fe-I & Fe-II Removal and Releaching Experiments

Fe-I Removal Experiments (at 90 °C, 120 minutes)• Fe-I Purification (at 90 °C, 120 minutes): Aim is max. Fe ppt. with min. Ni, Co, Sc ppt losses.

minutes)• Fe-II Purification (at 70 °C, 180 minutes): Aim is to precipitate all of the remaining Fe and Sc with

min. Ni and Co ppt losses.

• Releach: Aim is to obtain max Sc dissolution during releach.

Re-leaching of Sc rich Fe-II Precipitates (at 60 °C, 60 minutes)

A releach solution containing 153 mg/l Sc was obtained, and this solution was used for Sc recovery!

Exp-1 Exp-2 Exp-3 Exp-4 Exp-5 Exp-6 Exp-7 Exp-8 Exp-9

pH 2.00 pH 2.50 pH 2.75 pH 3.00 pH 3.25 pH 3.50 pH 4.00 pH 4.50 pH 5.00

Exp-1 Exp-2 Exp-3 Exp-4 Exp-5

pH 4.00 pH 4.25 pH 4.50 pH 4.75 pH 5.00

Exp-1 Exp-2 Exp-3 Exp-4

25 gpl H2SO4 50 gpl H2SO4 75 gpl H2SO4 100 gpl H2SO4

Our Scandium Concentrate

16Leuven, 20155-7 October ~15% Sc containing precipitate produced in META R&D Laboratory.

[1]- Riggall, S., ‘Australian scandium supply - A paradigm shift for a strategic metal’, in AeroMat 2015Conference, Long Beach, California, 2015.

[2]- Kaya Ş, Topkaya Y.A., ‘High Pressure Acid Leaching of a Nickel Laterite Ore to Extract Scandium’, in 1st European Rare Earth Resources Conference, Milos, Greece, 2014.

REFERENCES


THANK YOU for YOUR ATTENTION

18

Special Thanks to;

For their endless support to this study.Leuven, 20155-7 October

METU, META and MEAB Collobaration

19

Dr. Carsten Dittrich, MEAB

Dr. Bülent Şentürk, META

Prof. Dr. Yavuz A. Topkaya, METU/META

Poor Şerif Kaya :), METU


Products obtained after Fe-I Removal Exp.

1.Characterization

22

Physical Characterization:

• Moisture content: ~14% moisture in as-received ore (-2 mm) • Bulk Density: 1.08 gr/cm3 (as received -2 mm)• Solid Density: 3.51 gr/cm3 (by He pycnometer)• Magnetic Character: Very weak magnetic minerals (no separation)

Chemical Characterization:

Table 1 Chemical analysis of the laterite ore sample Constituent Fe Ni Co Sc (ppm) Al2O3 MnO MgO

Content (wt. %) 46.2 1.54 0.093 106 3.61 1.04 0.71

Constituent Cr2O3 SiO2 CaO Na2O K2O As S

Content (wt. %) 2.25 14.56 0.98 0.02 0.02 0.12 0.02

29 October 2015

1.Characterization

23

Mineralogical Characterization:

By X-Ray Analysis:

Major Phases: Hematite, Goethite, QuartzMinor Phases: Kaolinite and Nimite (Clay minerals)

By SEM Analysis:

Nickel is distributed in: Iron oxides and clay mineralsCobalt is distributed in: Clay mineralsScandium is distributed in: No detection. But, strong correlation of Sc distribution with Fe and Clay minerals (Al-Si) in wet screen analysis.

By DTA/TGA Analysis: Presence of the found minerals were counter-checked.

29 October 2015

Mine Site & ~5000 tons of Stock

Li

monitic

Zone

Hematitic

Zone

24

presented by Şerif kaya prof. dr. yavuz a....

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