1. Amphoteric Locust Bean Gum based Terpolymer/ Bentonite Composite Hydrogel: Preparation, Swelling and Dye Adsorption Studies.
Sirajo Abubakar Zauro and Vishalakshi B*
Department of Post-Graduate Studies and Research in Chemistry, Mangalore University, Mangalagangothri, , Karnataka, India
1. INTRODUCTION
SEM
Dye adsorption studies
The clay-polymer composite have been gaining increased attention by researchers due to the hybrid properties they exhibit [1]. The presence of coloured pollutant especially non-biodegradable, toxic and carcinogenic dye becomes a major threat to water bodies [2]. The removal of these pollutants from waste water by means of cheaper and eco-friendly techniques is a major challenge. Hence, the use of materials such as polymeric composite hydrogels became increasingly adapted for the removal of dyes from waste water [3-5].
Based on the available literature, the information on LBG based graft copolymers and clay composite were limited and no data was reported on the adsorption of Indigo Carmine (IC) dye by the LBG graft copolymers. Hence, it forms the basis of this research.
Fig. 5: a. First order adsorption kinetics, b. Second order adsorption kinetics of IC dye on the composite gel
Fig 3: SEM images of a) LBG , b) LBG-g-PDADMAC, c) LBG-g-Poly(DADMAC-co-AMPS) and d) LBG-g-Poly(DADMAC-co-AMPS)/BNT
2. Methodology
The surface is fibrous-like
d. Coarse and undulant surface
b. Homogeneous
c. Cotton-like irregular shape
60 0C
DADMAC, AMPS
BNT
LBG
LBG.
Fig. 6: Freundlich isotherms model for, a. LBG-g-poly(DADMAC-co-AMPS), b. LBG-g-poly(DADMAC-co-AMPS)/BNT
APS
MBA, MW(350w)
Table 1: Second order swelling kinetics data of the terpolymer composite gel
Swelling studies
LBG-g-poly(DADMAC-co-AMPS)
LBG-g-poly(DADMAC-co-AMPS)/BNT pH
Seq exp
Seq cal.
ks ×10-3 R2
1.2
5.70
5.88
9.96
0.999
5.95
6.37
4.09
0.995
7.0
7.09
7.35
7.50
16.52
18.87
8.29
0.994
9.0
7.16
7.63
4.49
0.997
8.42
8.77
5.02
0.998
= BNT
= MBA
= DADMAC
= AMPS
= LBG
LBG-g-poly(DADMAC-co-AMPS)
LBG-g-poly(DADMAC-co-AMPS)/BNT
3. Results
Table 2: Adsorption kinetics data of IC dye on terpolymer composite gel
Order
LBG-g-poly(DADMAC-co-AMPS)
LBG-g-poly(DADMAC-co-AMPS)/BNT
qe exp
qe cal. k1 R2 K1
1st
17.36
77.90
0.0046
0.970
11.99
-16.40
0.000
0.865
2nd
18.58
0.0012
0.999
12.35
0.0022
0.998
FTIR
OH str
c. In addition to the peaks in (a and b)
C-H str
C-O str.
N-H bend.
C-O-H vib
S-O str. from SO3H
C-N str.
Si-O str.
C=O str.
Si-O-Al bend.
C-N+ str.
Si-O-Si str.
Table 3: Adsorption isotherms data of IC dye on terpolymer composite gel
Langmuir isotherm model
Freundlich isotherm model qm KL RL R2 n kf
LBG-g-poly(DADMAC-co-AMPS)
111.11
0.01
0.678
1.07
0.50
0.999
LBG-g-poly(DADMAC-co-AMPS)/BNT
10.31
0.14
0.961
1.98
1.71
Fig. 4: a.Swelling capacity at different pH, b. Second order swelling kinetics of the terpolymer composite gel under different pH.
4. Conclusion
In this work terpolymer composite gel consisting of LBG, DADMAC, AMPS and BNT clay was made via microwave irradiation. The terpolymer without clay showed highest swelling at pH 7.0, and followed second order kinetics in all the pH conditions. The adsorption data of IC on the terpolymer showed maximum adsorption of 17.36mg/g of terpolymer composite without clay compared to mg/g of the clay composite terpolymer. The adsorption isotherms were observed to fit best into Freundlich model.
Fig.1: FTIR Spectra of a. LBG, b. LBG-g-PDADMAC, c. LBG-g-poly(DADMAC-co-AMPS) and d. LBG-g-poly(DADMAC-co-AMPS)/BNT
TGA
5. References
1st step – C %
c. 1st step – C %
2nd step – C %
2nd step – C %
3rd step – 560 0C %
3rd step – C %
4th step – 640 0C %
b. 1st step – 150 0C %
as char.
2nd step – 340 0C %
3rd step – 550 0C %
d. 1st step – C %
2nd step – C %
3rd step – C %
4th step 510– 630 0C %
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[4]. R. Jiang, Y. Fu, H. Zhu, J. Yao, L. Xiao, J. Appl. Polym. Sci. 125 (2012) 540–549
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6. Acknowledgement
One of the authors SAZ thanks the Government of India for providing the scholarship under Indian Council for Cultural Relations (ICCR).
Fig 2: TGA curves of a. LBG, b. LBG-g-PDADMAC, c. LBG-g-poly(DADMAC-co AMPS) and d. LBG-g-poly(DADMAC-co-AMPS)/BNT
*Correspondence:
9th KSTA Annual Conference, 20th to 21st December, Christ University Bengaluru