Clay is a fine grained natural rock or soil material that combines one or more clay minerals with traces of metal oxide and organic matter found abundantly on earth’s crust. Chemically it consists essentially of hydrated silicates of aluminum. Generally clays are used as solid acid catalysts, which can function as both Bronsted and Lewis acids in their natural and ion-exchanged form and also known as radical catalyst. Using clay catalysts, environmentally benign green chemistry can be done both at industrial and laboratory scale.The objective of this work is to study the behavior of calcium bentonite clay treated with sulfuric acid of 3N concentration under mechanical stirring and refluxing condition separately.The XRF and SEM studies indicated clearly the leaching and disintegration of the clay sheet upon thermo-chemical treatment. XRD studies of the acid treated clay indicated the structural transformation of the clay sheet upon acid treatment and became amorphous . As the treatment of 3N sulfuric acid chemically and thermo-chemically occur, Al2O3, TiO2 and Na2O contents in the acid treated material decreased progressively simultaneously increasing the SiO2 content. FTIR study of the acid treated clay shows that the acid treatment did not cause much variation in the peak pattern, however thermo-acid treatment in same acid strength the peak intensity was found to decrease progressively and indicating the dehydroxylation and successive leaching of the Al ions from the octahedral layer. Again, the BET surface area analysis of the samples indicated that method can be useful for manufacturing a surface active and high surface area material which can be used for catalyst as well as an adsorbent.

1. SURAYAKANTA PARIDA
M.SC 2ND
YR 4TH
SEM
ROLL NO-14050036
UNDER THE SUPERVISION OF
Dr. ACHYUT KUMAR PANDA (ASST.PROFESSOR)
DEPARTMENT OF CHEMISTRY
VSSUT ,BURLA.
09/26/18 1

2.  INTRODUCTION
 Solid acid catalyst
 Clay: A solid acid catalyst
 Bentonite
 Application of calcium bentonite
 EXPERIMENTAL PROGRAMME
 Materials
 Acid activation
 RESULTS AND DISCUSSION
 XRF Result
 XRD Result
 FTIR Result
 TGA Result
 SEM Result
 BET surface area Result
 CONCLUSION
09/26/18 2
CONTENTS

3. SOLID ACID CATALYST
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 Solids that possess acidic properties on their surface function as catalyst just
like liquid acid, such as H2SO4 and HCl.
In industrial scale chemistry, many processes are catalyzed by “solid acid’’.As
heterogeneous catalysts, solid acid don’t dissolve in the reaction medium.Well
known example are zeolites, alumina and various other metal oxide.
Some advantages are…….
1. separation of the products from the reaction medium is easy.
2. Catalyst can be separated easily and reused several times without loss of activity.
3. Reaction are generally clean and products are obtained in high purity.
4. Thermal and chemical stability during the reaction process and for batch reaction
during the separation stage.
5. Accessibility and good dispersion of active sites….

4. CLAY: A SOLID ACID CATALYST
 Clay is a fine grained natural rock or soil material that combines one or
more clay minerals with traces of metal oxide and organic matter found
abundantly on earth’s crust. Chemically it consists essentially of hydrated
silicates of aluminum.
 Generally clays are used as solid acid catalysts, which can function as both
Bronsted and Lewis acids in their natural and ion-exchanged form and
also known as radical catalyst. Using clay catalysts, environmentally
benign green chemistry can be done both at industrial and laboratory
scale.
09/26/18 4

5. BENTONITE
Bentonite is phyllosilicate clay consisting mostly of Montmorillonite. For
industrial purposes, two main classes of bentonite exists: Na and Ca bentonite.
Chemically calcium bentonite is a 2:1 layer sheet structured with one
octahedrally gibbsite [Al2(OH)6] sandwiched between two sheets of tetrahedrally
coordinated silicate [SiO4]4-
sheet.
09/26/18 5
Ref;-Gopalpur Nagendrappa. Organic Synthesis using Clay Catalysts Clays for ‘Green Chemistry’. Resonance (2002)64-77.

6. APPLICATION OF CALCIUM BENTONITE(CB):-
Bentonites have very ample and attractive properties
which gives them a wide and diverse range of uses.
Applications include:
i. Molding Sand
ii. Drilling Mud
vi. Physical Land
vii. Manufacture of Soap
Viii. Animal Feed
 ix. Catalytic applications
X . Synthesis of Aziridines and benzimidazoles
xi. Synthesis of aryl and alkyl ester.
09/26/18 6
Ref:-www.market izer.com. Uses and application of bentonite. Quiminet. 2012

7. 09/26/18 7
EXPERIMENTAL PROGRAMME
The objective of this work is to study the behavior of calcium bentonite clay treated with sulfuric acid of
3N concentration under mechanical stirring and refluxing condition separately.
1. Materials
 Calcium bentonite clay: SiO2 53.02%, Al2 O3 20.34%, Fe2 O3 9.39%, MnO 0.08%, CaO
4.85%, Na2O 0.33%, TiO2 1.14%, P2O5 0.03%, V2O50.09% and loss on ignition 10.72%.
 H2SO4
 Distilled water.
2.Acid activation
Figure 1(a) Acid activation using mechano 1(b) Acid activation using thermo chemical
treatment
chemical treatment.

8. 09/26/18 8
RESULTS AND DISCUSSION
1.XRF Result of CB:-
Components
(%) CB
Acid
treated CB
Acid and Thermal treated
CB
Al2O3 20.34 17.40 15.34
Fe2O3 9.39 7.71 4.65
TiO2 1.14 1.27 1.26
SiO2 53.02 57.52 65.04
Na2O 0.33 0.35 0.36
CaO 4.85 3.65 0.00
P2O5 0.03 0.03 0.03
V2O5 0.09 0.09 0.09
ZnO 0.00 0.00 0.00
MnO 0.08 0.08 0.08

9. 2. XRD Result of CB:-
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10 20 30 40 50 60 70
0
500
1000
1500
2000
2500
3000
3500
4000
B
A
CB
Acid treated CB
Thermal and acid treated CB
COUNTS
Degree 2θ
30
28
26

10. 09/26/18 10
400 800 1200
10
20
30
40
50
60
70
80
90
100
Transmittance(%)
Wave number (Cm
-1
)
CB
Acid Treated CB
Thermal and acid treated CB
675
595
614
800
873
1026
1200 1600 2000 2400 2800
10
20
30
40
50
60
70
80
90
100
Transmittance(%)
Wave number (Cm
-1
)
CB
Acid Treated CB
Thermal and acid treated CB
17121630
1638
1689
3000 3200 3400 3600 3800 4000
40
50
60
70
80
90
100
Transmittance(%)
Wave number (Cm
-1
)
CB
Acid Treated CB
Thermal and acid treated CB
3429 3580
3435
3437
Band (cm−1
) Assignments
3429 Al–O–Hstr(physisorbed water)
3435, 3437, 3580 Al–O–Hstr(structural hydroxyl
groups, octahedral)
1630 H–O-Hbending (physisorbed)
873 Al–Al–OHstr
1026, 800 Si–Ostr
755 Si–O–Alstr
614, 595 Si–Ostr, Si–O–Alstr
3. FTIR Result of CB:-

11. 4. TGA Result of CB:-
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100 200 300 400 500 600 700 800 900
84
86
88
90
92
94
96
98
100
102
Weight(%)
Temperature (
0
C)
CB
Acid treated CB
Thermal and Acid treated CB
Following TGA analysis shows that about 96.94% weight was obtained at 115.5◦
C in the case of untreated
calcium bentonite whereas about 95.5% weight was obtained at 106.23◦
C in the case of acid treated calcium
bentonite. But in case of thermal and acid treated calcium bentonite, about 94.72% weight was obtained at
105.62 ºC.

12. 5. SEM Result of CB:-
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Catalyst Surface area m2
/g
CB 146
Acid treated CB 193
Thermal and acid treated CB 290
a. CB b. Acid treated CB c. Thermal and acid treated CB
6. BET Surface area result of CB:-

13. 09/26/18 13
The XRF and SEM studies indicated clearly the leaching and disintegration
of the clay sheet upon thermo-chemical treatment.
XRD studies of the acid treated clay indicated the structural transformation
of the clay sheet upon acid treatment and became amorphous .
As the treatment of 3N sulfuric acid chemically and thermo-chemically
occur, Al2O3, TiO2 and Na2O contents in the acid treated material decreased
progressively simultaneously increasing the SiO2 content.
FTIR study of the acid treated clay shows that the acid treatment did not
cause much variation in the peak pattern, however thermo-acid treatment in
same acid strength the peak intensity was found to decrease progressively
and indicating the dehydroxylation and successive leaching of the Al ions
from the octahedral layer.
Again, the BET surface area analysis of the samples indicated that method
can be useful for manufacturing a surface active and high surface area
material which can be used for catalyst as well as an adsorbent.
CONCLUSION:-

14. 09/26/18 14