1. FLOTATION
(Main feature - hydrophobicity)

2. Flotation

3. water 
gas bubble
particle
Contact angle

4. Contact angle of selected materials
( degree)

5. Methods of measurement

7. The Young equation g cg sg scg s c  vapor adsorption
x x x x x x x x x x
x x x x x g
cg
sg
scg s c 
vapor adsorption
sg = sc+ cgcos
s -  = sc+ cgcos
liquid drop cieczy

8. Influence of pH (electrical properties) on flotation

9. Structure of electrical double layer

10. (rigid and diffuse layer )
Models of electrical double layer
o i j d
H+ K+ K+H2O
OH- A- A-H2O o
Helmholz
(flat condenser)
Gouy-Chapman
(diffuse layer)
Stern
(rigid and diffuse layer )
Grahame
(binding sites)
triple
layer
quadruple i
o d ----- H+
OH-
o i d-----
o -o d
o i d----
H+ K+
OH- A-
0 =  0  0
Flat condenser
Diffuse condenser

11. Formation of electrical double layer
+ n X- or
positive
surface charge
negative
place of particle breakage
+ n Me+
   
 Me  Me  Me  Me 
H2O
metals ęć
 
 Me Me 
 Me -
 Me  Me 
+ electrons
 Me  O  Me  O 
 O  Me  O  Me 
 Me  O  Me  O 
 O  MeO-
 Me  OH
 Me  X  Me  X 
 X  Me  X  Me 
 Me  X  Me  X 
 Me  X
 X -
 X  Me
 Me+
+ n H+
 O  MeOH2+
+ n OH-
oxides
salts
particle /water interface

12. Formation of electrical double layerMe S H 2 O OH SH
+ H +
+ n OH -
other
lad

16. Flotation reagents
COLLECTORS
for hydrophobization
FROTHERS
for froth creation
MODIFIERS
for enhancing

17. COLLECTORS

18. hydrophobization

19. Structure of collector
CH3CH2CH2CH2 CH2CH2CH2CH2
head
(hydrophilic)
tail
(hydrophobic)
COO–

20. collector renders the
surface hydrophobic
gas
collector
particle

21. Influence of pH and iep on flotation for various collectors

23. Collectors