Encyclopedie de la recherche sur l'aluminium au Quebec - Edition 2014 | Page 34
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PRODUCTION D’ALUMINIUM // ALUMINIUM PRODUCTION
Characterization of pitches
(wettability, MICROSCOPIE, CHIMIE)
CARACTÉRISATION DU BRAI (MOUILLABILITÉ, microscopy, chemistry)
Caractérisation du brai
(mouillabilité, microscopie, chimie)
CHARACTERIZATION OF PITCHES (WETTABILITY, MICROSCOPY, CHEMISTRY)
Ying LU1, Duygu KOCAEFE1, Yasar KOCAEFE1, Xianai HUANG1,
Dipankar BHATTACHARYAY1,Brigitte MORAIS2
CHAIRE DE RECHERCHE UQAC /
AAI SUR LE CARBONE
Université du Québec à Chicoutimi. 555 Boulevard Université, Chicoutimi, QC G7H 2B1
2 Aluminerie Alouette Inc. 400, Chemin De La Pointe-Noire, Sept-Îles, QC G4R 5M9
1
CHAIRE DE RECHERCHE UQAC/AAI SUR LE CARBONE
Introduction
Methodology
Sessile Drop Wetting Test
• Pitch properties strongly affect the properties of
anodes. Pitches show significant differences in their
chemical composition depending on different origins.
• Four different coal tar pitches and their mixtures were
studied to understand the interaction between these
pitches and one calcined petroleum coke by using the
sessile-drop test. Contact angle decreases with
increasing time. Smaller contact angle means better
wettability.
• The chemical properties of coke and pitch were studied
using FTIR and XPS. Their structures were
characterized with SEM and optical microscopy.
Pitch-Coke Drop
FTIR
XPS
•
•
•
•
•
Sessile Drop Wetting Test
FTIR
XPS
SEM
Optical Microscopy
FTIR
Pitch-1 & Pitch-2
100
100
Pitch-4
90
Pitch-2
60
Pitch-1
50
40
30
20
Pitch-2 (25%) & Pitch-1 (75%)
80
Contact Angle (°)
70
Pitch-2 (75%) & Pitch-1 (25%)
90
Pitch-3
80
Pitch-2 (100%)
70
Pitch-1 (100%)
60
50
40
30
20
10
10
0
150
200
250
0
300
0
Time (s)
50
T.I.
Coking
Value
Pitch-1
0,974
0,453
0,875
0,983
Pitch-2
0,984
0,920
0,983
0,987
Pitch-3
1,000
1,000
1,000
1,000
100
250
300
Pitch-3 (100%)
90
Pitch-2 (25%) & Pitch-3 (75%)
80
(°)
Q.I.
200
Pitch-2 & Pitch-3
60
0,983
0,680
0,946
0,995
4000
0
50
100
150
200
250
300
Time(s)
Total number
Particle count
2500
2000
CHa l
C-N
1500
Wave length (cm -1)
Sample
type
Pitch-1
Pitch-2
Pitch-3
Pitch-4
Coke
C(%)
O(%)
N(%)
OH
1000
500
S(%)
90.03
94.4
98.44
91.71
97.41
5.21
2.64
0.76
4.38
1.98
3.5
2.42
0.43
2.94
0.46
1.25
0.54
0.37
0.98
1.15
Sample
type
Pitch-2
Pitch type
Pitch-3
QI particle size distribution in pitch
Pitch-1
Pitch-2
Pitch-3
Pitch-4
C=C
C-C
Pitch-1
64.05
21.98
8.56
Pitch-2
Pitch-4
64.99
25.08
Pitch-3
74.36
21.08
Pitch-4
75.65
Coke
76.83
CN/CO/CS C=O/CSO2
Deconvoluted C1s peak of Pitch-1
COOH
3.93
1.47
3.54
1.5
4.88
2.99
0.37
1.2
15.31
6.72
1.16
1.16
17.49
3.22
1.23
C1s
C=C
C-C
C-N/C-O/C-S
C=O/CSO2
1.23
291
289
287
285
Binding Energy (eV)
283
281
Table 4 : Oxygen (O1s) functionality of different samples
Conclusions
•The chemical and physical properties of pitches contribute to
their wettability of coke.
•The QI particle size and distribution in pitches play a significant
role in the wettability of coke by pitch.
Pitch-4/Coke
3000
Table 3 : Carbon (C1s) functionality of different samples
•The wettability increases with increasing O, N, and S content
in pitch. The presence of COOH and NR3 groups might induce
an interaction in the pitch mixtures.
Pitch-3/Coke
NH/C=Ca r/C=O
3500
Table 2 : Atomic percentages of different samples
10
Particle count
Pitch-2/Coke
C=O
C C
C-S
XPS
20
Pitch-4
SEM
CHa l
30
Particle size
Pitch-1/Coke
CHa r
40
Pitch-1
Brigitte Morais
Aluminerie Alouette Inc.
OH COOH
50
Pitch-2
Pitch-3
NH
Free Moiture
OH
Optical Microscopy
Pitch-1
CHar
C-O
Pitch-2 (100%)
0
Pitch-4
The FTIR Spectra of Coke (Arunima Sarkar 2013)
Coke
Pitch-2 (75%) & Pitch-3 (25%)
70
Contact Angle
S.P.
150
Time(s)
Table 1:The properties of different pitches
Pitch
type
100
Intensity (CPS)
100
Acknowledgements
The technical and financial support of Aluminerie Alouette Inc. as well
as the financial support of the Natural Sciences and Engineering
Research Council o