Transcript Bez tytułu slajdu - Politechnika Wrocławska

FLOTATION
OF MINERAL
MATERIALS
Classification of materials according to their
ability to flotation
Class
Example
Applied collectors
Non-metals and solids with
sulfur, graphite, coal, talc hydrocarbons, nonionic liquids
significant natural hydrophobicity
insoluble in water
Native metals and sulfides
Oxidized minerals of non-ferrous
metals
Oxides, hydroxides and silicates
Sparingly soluble salts
Soluble salts
gold, chalcocite
chalcopyrite, galena
sfalerite
cerusyte, smitsonite
malachite, tenorite,
cuprite
hematite, ilmenite
corundum, cassiterite
chromite, feldspars
kaolinite
fluorite, barite, calcite,
apatite, dolomite
halite, silvinite, carnalite
kiserite
xanthates, aerofloats
xanthates (after sulfidization)
siarczkowaniu), anionic and
cationic
anionic and cationic (with and
without activation using metal
ions)
anionic and cationic
cationic, seldom anionic
Class 1. Naturally hydrophobic materials
Graphite, talc, sulfur, some sulfides, coals
collectors: apolar compounds which increase
hydrophobicity and speed up flotation
Simplified model of coal unit
80
H
contact angle, degree
H
H
H2C
H
H
H3C - CH
OH
CH2
80
70
sessile drop
60
50
40
bubble attachment
30
r
20
10
captive bubble
flotometry
weg2
0
contact angle, degree
0
2
4
6
8
10
12
14
moisture content, %
60
40
Contact angle depends on method
coal
of measurement
20
0
80
82 84 86 88 90 92
carbon content in coal , %
94
Hydrophobicity of coal vs. coalification degree
Zeta potential (and electrical charge)
depends on coalification degree
4
0
6
8
pH 10
100%
20
80
hy
dr
og
en
zeta potential, mV
ing
ite
2
cok
0
rac
10
8
6
4
2
0
h
ant
s
inou
itum
subb
+
60
40
en
yg
ox
oxid
60
ized
40
cellulose
brown
80
lignin
100%
20
hard coal
antracite
graphite
0
20
40
60
80
100%
carbon
Coalification vs H, O, and C content in natural carbonaceous matter
Class 2. Native metals and sulfides
A) Metals occurring in nature: iron, mercury,
copper, gold, platinum metals
B. Sulfides:
lead (galena, PbS)
copper (chalcocite, covellite, chalcopyrite,
bornite)
silver (argentite)
zync (sphalerite)
Class 2. Native metals and sulfides
Table 12.36. Collectors containing sulfur applied for flotation of sulfides (after Aplan i Chander, 1988)
Collector type
Mercaptan
Dithiocarbonate
(xanthate)
Formula
Chemical name
R–SH
R–O–(C=S)–SK
R–O–(C=S)–SNa
potassium ethyl
sodium ethyl
Xanthogen
formate
322
Z–9
sodium isopropyl
343
Z–11
potassium butyl
–
Z–7
sodium isobutyl
317
Z–14
–
Z–8
sodium sec-butyl
301
Z–12
potassium amyl
355
–
sodium amyl
350
Z–6
potassium sec-amyl
–
Z–5
potassium hexyl
–
Z–10
R–S–(C=S)–SNa
Philips (Orform
C0800)
R–O–(C=S)–S–(C=O)–OR´
Dow
R=ethyl, R´=ethyl
R=izopropyl, R´=ethyl
(R–O–)2(P=S)–ONa
Dithiophosphate
(R–O–)2(P=S)–SNa
Dithiophosphinate
Thiocarbamate
B
R=amyl, R´=allyl
3302
1750
R=heksyl, R´=allyl
3461
2023
Amcy 194, 3394
AmCy (Aerofloat)
Aerofloat 211, 243
sodium di-izobutyl
Aerofloat 3477
sodium di-isoamyl
Aerofloat 3501
sodium di-iso-sec-butyl
Aerofloat 238
sodium di-methylamyl
Aerofloat 249
cresylic acid+P2S5
Aerofloat 15
(R–)2(P=S)–S–Na
AmCy3418
R–(NH)–(C=S)–OR´
Mercaptobenzothiazole
(C6H5NH2)C=S
(thiocarbanilide)
Na Aerofloat
sodium di-isopropyl
Dow
Minerec
N-methyl-O-isopropyl
–
1703
N-methyl-O-butyl
–
1331
N-methyl-O-isobutyl
–
1846
N-ethyl-O-isopropyl
Z–200
1661
–
1669
N-ethyl-O-isobutyl
Thiourea
derivatives
2048
Minerec
sodium diethyl
(R–O–)2(P=S)–SH
A
–
–
R–O–(C=S)–S–R’
Monothiophosphat
e
Minerec
Z–1
AmCy
R=butyl, R´=ethyl
Xanthic ester
Pennwalt, Philips
AmCy
Dow
303
Z–3
325
Z–4
potassium isopropyl
potassium sec-butyl
Trithiocarbonate
Manufacturer and
designation
AmCy Aero. 130
Seria AmCy 400
100
-4
2x10 M KEtX
flotation recovery, %
80
60
-5
10 M KEtX
40
20
pyrite
0
0
2
4
6
pH
8
10
Xanthate flotation of pyrite
12
Class 3. Oxidized minerals of non-ferrous metals
cerussite (PbCO3)
vanadinite (Pb5[Cl(VO4)3])
anglesite (PbSO4)
malachite (CuCO3·Cu(OH)2
azurite (2CuCO3·Cu(OH)2)
chrysocolla (hydrated copper silicate)
tenorite (CuO)
cuprite (Cu2O)
smithsonite (ZnCO3)
Class 3. Oxidized minerals of non-ferrous metals
Approaches:
1. Sulfidization
2. Flotation using either cationic or anionic
collectors (as in the case of oxide-type minerals)
Class 4. Oxides and hydroxides
Consists of simple oxides (Fe2O3, SnO2),
oxyhydroxides (AlOOH) as well as complex
oxides and complex hydroxides (spinels,
silicates, aluminosilicates).
Table 12.38. Influence of structure of silicates on their flotation with
anionic and cationic collectors (after Manser, 1975)
Collector
Anionic
Cationic
orthosilicates
good
satisfactory*
* Flotation depends on pH
Silicate group
pyroxene
amphibole
week
none
satisfactory *
good
frame
none
very good
Class 4. Oxides and hydroxides
100
flotation recovery, %
80
varous minerals
60
40
albite
20
quartz
0
2
4
6
8
10
12
pH
Oleate flotation of oxide and silicates
Class 4. Oxides and hydroxides
flotation recovery, %
100
80
QUARTZ
60
40
20
18
16 14
12
10
8
6
4
0 -08
-07
-06
-05
-04
-03
-02
-01
00
10 10 10 10 10 10 10 10
10
amine concentration, kmol/m 3
Amine flotation of quartz
Class 5. Sparingly soluble salts
Table 12.44. Solubility product (Kr) for selected compounds at 293 K (after Barycka and Skudlarski, 1993)
Compound
1
Fluoride
CaF2
SrF2
MgF2
Chloride
AgCl
PbCl2
Bromide
AgBr
PbBr2
Iodide
AgI
PbI2
Carbonate
PbCO3
ZnCO3
CaCO3
MgCO3
Hydroxide
Fe(OH)3
Zn(OH)2
Mg(OH)2
Ir
2
4,0·10–11
2,5·10–9
6,5·10–9
1,8·10–10
1,7·10–5
4,6·10–13
2,8·10–5
8,3·10–17
7,1·10–9
7,2·10–14
1,7·10–11
7,2·10–9
3,5·10–8
4,5·10–37
3,3·10–17
1,2·10–11
Compound
3
sulfite
BaSO4
SrSO4
CaSO4
sulfide
HgS
Ag2S
Cu2S
CuS
PbS
ZnS
NiS
CoS
FeS
MnS
cyanide
Hg2(CN)2
CuCN
chromate
PbCrO4
BaCrO4
CuCrO4
Ir
4
9,8·10–11
6,2·10–7
9,1·10–6
1,9·10–53
6,3·10–50
7,2·10–49
4,0·10–36
6,8·10–29
1,2·10–28
1,0·10–24
3,1·10–23
5,1·10–18
1,1·10–15
5,0·10–40
3,2·10–20
2,8·10–13
1,2·10–10
3,6·10–6
Class 5. Sparingly soluble salts
100
SDS
recovery, %
80
DDA
60
fluorite
40
NaOl
20
0
2
4
6
8
10
12
14
pH
NaOl - sodium oleate, DDA-dodecylamine,
SDS,- sodium dedecyl sulfite
Class 5. Sparingly soluble salts
100
chrysocolla
recovery, %
80
calcite
60
40
bastnesite
20
barite
0
0
2
4
6
8
10
12
14
pH
Flotation with potassium octylohydroxymate
Class 5. Sparingly soluble salts
100
recovery, %
80
60
fluorite
calcite
apatite
40
20
0
10
-06
10
-05
10
-04
sodium oleate concentration, mol/dm3
10
-03
Class 6. Soluble salts
Table 12.45. Sign of surface charge for selected soluble salts
(after Miller et al., 1992)
Salt
LiF
NaF
KF
RbF
CsF
LiCl
NaCl
KCl
RbCl
CsCl
LiBr
NaBr
Surface charge sign
measured
predicted*
+
+–
+
+
+
+
+
+
+
+
–
–
+
–
–
+
+
+
+
+
–
–
–
–
Salt
KBr
RbBr
CsBr
LiI
NaI
KI
RbI
CsI
NaI·2H2O
K2SO4
Na2SO4·10H2
O
Na2SO4
Surface charge sign
measured
predicted*
–
+
–
+
+
+
–
–
–
–
+
–
–
+
+–
+
–**
–**
–**
* Predicted from the ions hydration theory for inos in crystalline lattice (Miller et al., 1992).
** Hancer et al., 1997.
Class 6. Soluble salts
flotation recovery, %
100
80
Na 2SO4×10H2O
KCl
K2SO4
60
40
20
0 -06
10
NaCl
Na 2SO4
-05
-04
-03
10
10
10
10
dodecylamine hydrochloride, kmol/m 3
-02
Hallimond flotation cell
scale
capillary
drive
air
Laboratory Mechanobr flotation machine
AIR
FEED
Denver DR flotation machine
FEED
AIR
WATER
CONCENTRATE
CELL
Jameson flotation cell
ODPAD
FEED
(0,01 m/s)
water
(0,0005-0,003 m/s)
concentrate
FROTH LAYER
phase border
air bubbles
(0,5-3 mm)
FLOTATION
REGION
gas
(0,005-0,03 m/s)
TAILING
(~0,01 m/s)