Your SlideShare is downloading. ×
0
Development of Pt/Zirconia Catalyst for
liquid phase HI Decomposition Reaction
in S-I Cycle
Deepak Tyagi, Alisha Gogia, Sa...
Hydrogen as future fuel
• Hydrogen as a future source of energy is a scenario of
high probability and necessity, consideri...
ICAER-2013, IITB
Production of Hydrogen:
Today hydrogen is mainly produced from fossil resources.
Origin

Percent

Natural gas

48

Oil

30...
Production of Hydrogen from Water:
The two processes that have the greatest
likelihood of successful massive hydrogen
pro...
Sulfur - Iodine Cycle
Exothermic; T = 120 °C

Endothermic; T = 870 °C
9I2 + SO2 + 16 H2O
ICAER-2013, IITB

→

Endothermic;...
Hydriodic Acid Decomposition
Decomposition of hydriodic acid an integral part of Sulfur - Iodine
and Magnesium – Iodine t...
Catalyst reported for HI decomposition
Ceria

IJHE 34(2009) 1688-1695

Ni/Ceria

IJHE 34(2009) 5637-5644
IJHE 34(2009)87...
Objective of the present
Work
• Develop Pt catalysts over Zirconia support (with
different Pt loading)
• Demonstrate stabi...
Preparation of Catalyst
Zirconyl Nitrate solution
NH4OH solution added dropwise
with constant stirring

Zirconium Hydroxid...
Characterization:
•

XRD

•

SEM

•

FEG-SEM

•

N2 Adsorption

•

ICP OES

ICAER-2013, IITB
Intensity

X-Ray Diffraction:
120
100
80
60
40
20
0
120
10
100
80
60
40
20
0
120
10
100
80
60
40
20
0
10

ICAER-2013, IITB...
SEM & EDAX:

ICAER-2013, IITB
FEG-SEM:

ICAER-2013, IITB
Adsorption and Desorption isotherms

1% Pt/ZrO2

ICAER-2013, IITB

2% Pt/ZrO2
Pore Size Distribution:

1% Pt/ZrO2
ICAER-2013, IITB

2% Pt/ZrO2
Surface Area:
S.
No
1.

Sample

Surafce Area Pore Size

Pore Volume

ZrO2

108.64

3.62

0.1125

2.

1%Pt ZrO2

139.71

3....
Activity & Stability of Catalysts
50 ml of 27% HI + 250 mg of Catalyst
Heated for 2h at ~ 120oC
Filtered
Filtrate analyzed...
Activity & Stability of Catalysts
HI ←
→ 1 I 2 + 1 H 2
2
2
For liquid phase decomposition reaction, dissolution of the I2...
Activity Measurement
H+ Titration

I- Titration

Using Glass electrode

Using Ag/AgCl electrode

Titration against NaOH

T...
Activity and stability of the catalysts
S. No.

% Conversion

1.

0.5% Pt/ZrO2

13.9 %

2.

1% Pt/ZrO2

16.7 %

3.

ICAER-...
XRD Used Catalysts:
100
80

Used 2% Pt/ZrO2

60
40
20

Intensity

0
120
20
100
80
60
40
20
0
120
20
100
80
60
40
20
0
20

...
Comparison with Pt/Carbon catalysts
S.
No.

% Conversion
(H+ Titration)

1

Pt/Gr

17.5 %

2

Pt/SBA

15.0 %

3

Pt/MCM-C
...
Conclusions
Pt/Zirconia catalyst prepared was active for HI
decomposition.
The percentage conversion is dependent on nob...
ICAER-2013, IITB
Upcoming SlideShare
Loading in...5
×

82 deepak tyagi

261

Published on

Published in: Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
261
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
2
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • Hydrogen Use
  • Transcript of "82 deepak tyagi"

    1. 1. Development of Pt/Zirconia Catalyst for liquid phase HI Decomposition Reaction in S-I Cycle Deepak Tyagi, Alisha Gogia, Salil Varma, A. K. Tripathi, S. R. Bharadwaj Chemistry Division Bhabha Atomic Research Centre, Mumbai
    2. 2. Hydrogen as future fuel • Hydrogen as a future source of energy is a scenario of high probability and necessity, considering the illeffects of fossil fuel based systems on the environment and also the depleting natural resources. • The fast development of hydrogen based power sources like fuel cells will lead to more efficient and cleaner energy supply. • For this to be economically feasible, large scale production of hydrogen has to be attained by environment friendly route. ICAER-2013, IITB
    3. 3. ICAER-2013, IITB
    4. 4. Production of Hydrogen: Today hydrogen is mainly produced from fossil resources. Origin Percent Natural gas 48 Oil 30 Coal 18 Electrolysis 4 Total 100 In the long term, because of increasing energy demand, lack of fossil resources limitations on the release of green house gases Water suitable raw materials for hydrogen production. ICAER-2013, IITB
    5. 5. Production of Hydrogen from Water: The two processes that have the greatest likelihood of successful massive hydrogen production from water are (i) steam electrolysis (ii) thermochemical cycles. This way hydrogen can be produced from water at temperatures much lower than the direct water decomposition at 3000 °C. As heat can be directly used in thermochemical cycles, they have the potential of better efficiency than alkaline electrolysis. The required thermal energy can be provided by nuclear reactor (CHTR). ICAER-2013, IITB
    6. 6. Sulfur - Iodine Cycle Exothermic; T = 120 °C Endothermic; T = 870 °C 9I2 + SO2 + 16 H2O ICAER-2013, IITB → Endothermic; T = 450 °C (2HI + 10H2O + 8I2) + (H2SO4+ 4H2O)
    7. 7. Hydriodic Acid Decomposition Decomposition of hydriodic acid an integral part of Sulfur - Iodine and Magnesium – Iodine thermochemical cycle. Homogeneous azeotrope in HI-H2O binary system and thermodynamically limited slow gaseous HI decomposition - highly energy consuming step. 1.The General Atomic Co. proposed use of phosphoric acid (Extractive Distillation) for concentration of the HI solution to obtain 99.7% molar HI vapour. But, concentration of recycled phosphoric acid consumes large amount of heat and electricity. 2.Employment of electro-electrodialysis concentration method and hydrogen permselective membrane reactor also reported by JAERI. 3.Reactive distillation - combining reaction and separation in a single step leading to overall shift of equilibrium towards production of I 2 and H2. First reported by Roth et al in 1989. ICAER-2013, IITB
    8. 8. Catalyst reported for HI decomposition Ceria IJHE 34(2009) 1688-1695 Ni/Ceria IJHE 34(2009) 5637-5644 IJHE 34(2009)8792-8798 Ni/Alumina IJHE 34(2009) 4059-4056 Activated Carbon IJHE 34(2009) 4057-4064 Pt/Ceria IJHE 33(2008) 602 – 607 IJHE 33(2008) 2211-2217 Pt/Alumina Chinese chemical letters 20 (2009) 102-105 Pt/Ceria-Zirconia IJHE 35(2010) 445-451 “ D. R. O’keefe et al, Catalysis Reviews 22(3), 325-369 (1980)” ICAER-2013, IITB
    9. 9. Objective of the present Work • Develop Pt catalysts over Zirconia support (with different Pt loading) • Demonstrate stability of the catalysts under the reaction conditions • Evaluate activity of these catalysts for HI decomposition reaction • Derive structure activity correlation for development of future catalysts ICAER-2013, IITB
    10. 10. Preparation of Catalyst Zirconyl Nitrate solution NH4OH solution added dropwise with constant stirring Zirconium Hydroxide Gel Dried at 100°C for 6h Calcined at 350°C for 3h Zirconia (i) Add Chloroplatinic acid Dropwise With constant stirring (ii) Reduction by Hydrazine at RT (iii) Reduction by H2 flow at 300 °C Platinum Zirconia Catalyst
    11. 11. Characterization: • XRD • SEM • FEG-SEM • N2 Adsorption • ICP OES ICAER-2013, IITB
    12. 12. Intensity X-Ray Diffraction: 120 100 80 60 40 20 0 120 10 100 80 60 40 20 0 120 10 100 80 60 40 20 0 10 ICAER-2013, IITB 2 % Pt/ZrO2 20 30 40 50 60 70 1 % Pt/ZrO2 20 30 40 50 60 70 0.5 % Pt/ZrO2 20 30 40 2θ 50 60 70
    13. 13. SEM & EDAX: ICAER-2013, IITB
    14. 14. FEG-SEM: ICAER-2013, IITB
    15. 15. Adsorption and Desorption isotherms 1% Pt/ZrO2 ICAER-2013, IITB 2% Pt/ZrO2
    16. 16. Pore Size Distribution: 1% Pt/ZrO2 ICAER-2013, IITB 2% Pt/ZrO2
    17. 17. Surface Area: S. No 1. Sample Surafce Area Pore Size Pore Volume ZrO2 108.64 3.62 0.1125 2. 1%Pt ZrO2 139.71 3.72 0.1573 3. 2%Pt ZrO2 133.47 3.72 0.1492 ICAER-2013, IITB
    18. 18. Activity & Stability of Catalysts 50 ml of 27% HI + 250 mg of Catalyst Heated for 2h at ~ 120oC Filtered Filtrate analyzed for presence of Pt by ICP-OES & Used catalyst evaluated by XRD and SEM. ICAER-2013, IITB
    19. 19. Activity & Stability of Catalysts HI ← → 1 I 2 + 1 H 2 2 2 For liquid phase decomposition reaction, dissolution of the I2 formed at catalyst surface into the iodide solution as Ix- and continued intimate contact between HI and catalyst maintains high reactivity levels even in presence of I2. Upto 50% conversion is reported by O’Keefe et al for 48h study at room temperature. ICAER-2013, IITB
    20. 20. Activity Measurement H+ Titration I- Titration Using Glass electrode Using Ag/AgCl electrode Titration against NaOH Titration against AgNO3 NaOH was standardized using KHP AgNO3 was standardized using NaCl ICAER-2013, IITB
    21. 21. Activity and stability of the catalysts S. No. % Conversion 1. 0.5% Pt/ZrO2 13.9 % 2. 1% Pt/ZrO2 16.7 % 3. ICAER-2013, IITB Catalyst 2% Pt/ZrO2 18.5 %
    22. 22. XRD Used Catalysts: 100 80 Used 2% Pt/ZrO2 60 40 20 Intensity 0 120 20 100 80 60 40 20 0 120 20 100 80 60 40 20 0 20 30 40 50 70 Used 1% Pt/ZrO2 30 40 50 60 70 Used 0.5% Pt/ZrO2 30 40 50 2θ ICAER-2013, IITB 60 60 70
    23. 23. Comparison with Pt/Carbon catalysts S. No. % Conversion (H+ Titration) 1 Pt/Gr 17.5 % 2 Pt/SBA 15.0 % 3 Pt/MCM-C 17.0 % 4 Pt/Zirconia 16.7 % 5 Pt/AC 12.1 % 6 Pt/FS-C 7.2 % 7 ICAER-2013, IITB Catalyst Blank 2.8 %
    24. 24. Conclusions Pt/Zirconia catalyst prepared was active for HI decomposition. The percentage conversion is dependent on noble metal loading. Catalyst prepared was found to be stable under liquid phase HI decomposition conditions. Catalytic activity of Pt/Titania catalyst was better as compared to some of the Pt/C catalysts. ICAER-2013, IITB
    25. 25. ICAER-2013, IITB
    1. A particular slide catching your eye?

      Clipping is a handy way to collect important slides you want to go back to later.

    ×