1. 4 th InternatIonal ConferenCe on
advanCes In energy researCh
ICear-2013
IndIan InstItute of teChnology
MuMbaI (M.s) IndIa.
IONIC LIQUIDS:- ENERGY EFFICIENT GREEN SOLVENT FOR THE
EXTRACTIVE DESULFURIZATION OF LIQUID FUELS
Mr. Swapnil A. Dharaskar
Research Scholar
Under Supervision
Dr. Kailas L. Wasewar
&
Dr. Mahesh N. Varma
Department of Chemical Engineering
Visvesvaraya National Institute of Technology (VNIT)
Nagpur – 440010, Maharashtra, INDIA

2. objeCtIve
2

3. Imidazolium
1-butyl-3-methylimidazolium
Chloride
3
Pyridinium
1-butyl-3-methylimidazolium
Bromide
Phosphonium
Ammonium
1-butyl-3-methylimidazolium
Tetrafluoroborate
Sulfonium
1-butyl-3-methylimidazolium
Hexafluorophosphate

4. 4

5. Why Extractive desulfurization?
 In petroleum and hydrocarbon industries, various solvents such as ethers, amines,


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a)
b)
c)
d)
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alcohols and other volatile organic compounds have been used for the options like
extraction, absorption, azeotropic distillation etc.
These solvents have their own limitations in terms of environmental issue, recycle
ability, etc. which can be overcome by the use of ionic liquids as green solvent.
Among theses EDS seems more eye-catching because it does not require hydrogen
and catalyst and its operation conditions is mild.
Moreover, it does not alter the chemical structures of the compounds in fuel oils
and extracted S-compounds can be reused as raw materials.
A good extractant much have the following attributes:Good extractive ability for S-compounds.
Free of contamination to the fuels.
Non-toxicity, and environmental benignity.
Stability for repetitive use

6. Basic concept of Desulfurization
6

7. Characterization of ILs
FT-IR analysis of ionic liquids
1H-NMR and 13C-NMR analysis
Thermal Analysis
Conductivity Analysis
Solubility Analysis
Viscosity Analysis
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8. Results and Discussion
 Preparation of Model Fuel
A model liquid fuel with 500 ppmw sulfur (DBT as sulfur source)
was prepared in n-Octane. Similarly, the model liquid fuels were
prepared by dissolving BT, T, and 3-MT individually in n-Octane
respectively. Actual diesel and gasoline with total sulfur content of
385.13 and 180.79 ppmw respectively were used.
 Effect of Reaction Time on S-removal
 Effect of Reaction Temperature on S-removal
 Effect of S-Compound on S-removal.
 Recycling of spent ILs without Regeneration.
 Desulfurization of Real Fuels using imidazolium IL
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9. Effect of reaction time on DBT removal with IL
IL
Time (min)
S-content
(ppmw)
S-removal
(%)
Part. Coeff.
(KN)
5
214.55
57
1.33
[BMIM]BF4
10
199.05
60.2
1.51
20
184.55
63
1.71
30
170.05
66
1.94
5
223.55
55.3
1.24
[BMIM]PF6
10
209.55
58
1.39
20
194.05
61.2
1.58
30
181.5
63.7
1.75
Temperature = 30OC, Mass ratio of model fuel/IL = 5:1, Extraction time = 30
min. Initial sulfur concentration = 500 ppmw.
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10. Effect of reaction temperature on S-removal with IL
IL
Temperature S-content S-removal Part. Coeff.
(OC)
(ppmw)
(%)
(KN)
20
198.5
60.3
1.52
[BMIM]BF4
25
179.05
64.2
1.79
35
165.05
67
2.02
45
224.55
55
1.22
55
263.55
47.3
0.89
20
213.05
57.4
1.35
[BMIM]PF6
25
200.05
60
1.5
35
171.5
65.7
1.92
45
249.05
50.2
1.0
55
279.55
44
0.79
Temperature = 30OC, Mass ratio of model fuel/IL = 5:1, Extraction time =
30 min. Initial S-concentration = 500 ppmw.
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11. Effect of S-compound on DBT removal
IL
Scontent
(ppmw)
Sremoval
(%)
Part. Coeff.
(KN)
DBT
169.55
66
1.94
BT
180.49
63.9
T
231.09
3-MT
[BMIM]BF4
S-Compound
260.30
IL
S- content
(ppmw)
S-removal
(%)
Part.
Coeff.
(KN)
174.09
65.2
1.87
1.77
210.39
57.9
1.37
53.8
1.16
250.19
49.9
0.99
47.9
0.92
285.79
42.8
0.75
[BMIM]PF6
Temperature = 30OC, Mass ratio of model fuel/IL = 3:1, Extraction time = 30 min. Initial sulfur concentration = 500
ppmw.
Reactivity sequencing was DBT > BT > T > 3-MT.
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12. Recycling of spent ILs without regeneration
No. of Cycle
IL
S-removal (%)
1
66
[BMIM]BF4
2
55.4
3
48.5
4
36
1
63.7
[BMIM]PF6
2
53.4
3
45.2
4
31
Model fuel = (n-Octane + DBT), Mass ratio of model fuel/IL = 5:1, Temperature =
30OC, Extraction time = 30 min,
Initial S-concentration = 500 ppmw.
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13. Desulfurization of Real Fuels using ILs
IL
Diesel/IL
(Mass Ratio)
Scontent
(ppmw)
Sremoval
(%)
Part.
Coeff.
(KN)
Gasoline/IL
(Mass Ratio)
S-content
(ppmw)
Sremoval
(%)
Part.
Coeff.
(KN)
[BMIM]BF4
5:1
210.31
45.4
0.83
5:1
70.2
61.1
0.61
225.19
41.5
0.71
90.3
50
1.0
[BMIM]PF6
Temperature = 30OC, Extraction time = 30 min,
Initial S-concentration of diesel and gasoline = 385.13 and 180.79 ppmw.

14. Multistage Extraction Process
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15. Conclusion
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16. Highlights
 Imidazolium
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based (ILs) were synthesized and employed as an
Extractant for S-removal.
Imidazolium Ils can be used as energy efficient green material for
EDS of liquid fuels, mainly with regards to those S-compounds that
are very complex to remove by common hydrodesulfurization
(HDS) technique.
The spent IL could be reused for four times with a slight decrease
in activity.
Enormous saving on energy can be achieved by use of IL in
process.
This work could be present a new alternative for extractive deepdesulfurization of liquid fuels.
The EDS method could be option for environmentally benign
method for deep desulfurization.

17. ApplicAtion of ils
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18. Analytical Equipments Used
• Fourier Transform Infra Red (FTIR).
• Nuclear magnetic resonance (NMR)
• Differential Scanning Calorimetry (DSC).
• Thermogravimetric Analysis (TG/DTA).
• Thermo-scientific Total Sulfur Analyzer (TS-3000).
• Inductively coupled plasma-AES
• X-ray fluorescence spectrophotometer (XRF)
• UV visible Spectrophotometer.
• Gas Chromatography with mass spectometry (GC-MS)
High Pressure Liquid Chromatography (HPLC).
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19. Acknowledgement
s
CSIR
VNIT, Nagpur
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