NATIONAL WORKSHOP ON “NEW TRENDS IN BIOTECHNOLOGY: THEORY AND APPLICATIONS
ADSORPTION OF BASIC DYES ONTO LOWLOWCOST ADSORBENTS: ANALYSIS OF THE EQUILIBRIUM STATE
Dr. Abel E. Navarro Science Department, Borough of Manhattan Community College, CUNY
Color:
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Against the natural conception of pure water. It hides other types of pollution.
-
Prevents the penetration of sunlight into deep layers of water – Photosynthesis.
-
The biological risks have not been totally discarded (carcinogenic and toxic effects).
Use of biological techniques to remove pollutants from air, soil and water.
-
Bioaccumulation: Living organism
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Biosorption: Dead biomass
Use of non non--living biomasses to passively remove pollutants
Driven
by physico physico--chemical processes
Algae,
crustacean shells, eggshell, nutshell, fruit peels, fruit seeds, TEALEAVES TEALEAVES..
Fast kinetics (saturation time). time). Potential recyclability of waste
Complex structure, mainly formed by polysaccharides have many ways for pollutants to be taken up:
- Metabolism dependent. - Non Non--metabolism dependent.
Competitive performance. Pollutant selectivity. Cost effectiveness. Pollutant recovery. No sludge generation.
Eco Eco--friendly filtering technique.
Alternative for using
man-made resins (x10 manmore expensive).
Potentially used for air and water.
TARGET POLLUTANTS
Basic Blue 99: Naphthoquinoneimine, Naphthoquinoneimine, cationic dye. Amino and hydroxyl groups present.
O NH N
Cl N
N H3C
N
CH3 CH3
H3C
Basic Yellow (BY57) Basic Blue 99 (BB99)
OUR ADSORBENTS
Why? High content of functional organic groups such as alcohol (fiber and carbohydrates), carboxylic acids and amines (structural polysaccharides).
Widespread use of green tea as a hot/cold drink. Massive collection from green tea industries (i.e. Arizona and other bottled tea tea--based drinks).
RESULTS Characterization of the Adsorbents by TGA, SEM, FTIR, SURFACE AND POROSITY 0 -2
Mass Loss (%)
-4 -6 -8 -10 -12 -14
GT
-16 -18 0
100
200
300
400
500
600
0
Temperature ( C)
FTIR ANALYSIS
cm-1
O-H STRETCH
3436
N-H BENDING
1636
Micropore Volume (cm3/g)
0.692
C=O STRETCH
1656
Total Pore Volume (cm3/g)
1.106
C-O STRETCH
1111
C=O STRETCH
1720
Surface Area (m2/g)
2,735.00
pH Effect
-
Ionization of adsorbent’s surface and dye
-
Higher pH promotes higher adsorption.
Mass Effect Minimize amount of adsorbent. Higher adsorption promotes formation of aggregates.
100
95
90
90 85
70
% ADSORPTION
% ADSORPTION
80
60 50 40 30
80 75 70 65
20
BY57 BB99
10
BY57 BB99
60
0
55 2
3
4
5
pH
6
7
8
0
20
40
60
80
100
120
140
Adsorbent Mass (mg)
160
180
200
RESULTS
Isotherms were modeled by Langmuir and Freundlich theories.
0.20
BY57 BB99
Adsorption Capacity (g/g)
0.18 0.16
Langmuir qmax (g/g)
0.06
0.27
0.12
b (L/g)
63.29
25.82
0.10
R2
0.979
0.988
kF (L/g)
0.23
1.27
n
1.829
1.448
R2
0.984
0.978
0.14
0.08 0.06
Freundlich
0.04 0.02 0.00
0.02
0.04
0.06
0.08
0.10
Dye Concentration at Equilibrium (g/L)
0.12
Salinity Effect: Decreases adsorption due to competition for the adsorption sites.
-
Higher the charge, the stronger the effect. 95
NaCl NaNO3 Ca(NO3)2
80 70 60 50 40 30
NaCl NaNO3 Ca(NO3)2
90
% BB99 ADSORPTION
90
% BY57 ADSORPTION
-
85 80 75 70 65 60 55
20
50 0.0
0.1
0.2
0.3
Salt Concentration (mol/L)
BY57
0.4
0.5
0.0
0.1
0.2
0.3
Salt Concentration (mol/L)
BB99
0.4
0.5
Presence of Heavy Metals - Large and positively charge ions. - Present in residual waters. 80
Cu(II) Pb(II)
% BB99 ADSORPTION
% BY57 ADSORPTION
100
Cu(II) Pb(II)
60
40
20
0 0
10
20
30
40
Heavy Metal Concentration (mg/L)
BY57
50
80
60
40
20
0 0
10
20
30
40
Heavy Metal Concentration (mg/L)
BB99
50
Green Tealeaves have proven to be promising adsorbents for model dyes BY57 and BB99. TGA, FTIR, surface/porosity and SEM studies report advantages of GT as an alternative adsorbent. Langmuir and Freundlich isotherms modeled the adsorption indicating a qmax of 0.06 and 0.27g/g for BY57 and BB99, respectively. Salinity and heavy metals have a negative effect on the adsorption of both dyes, due to competition for adsorption sites.
Group Members:
Acknowledgements
Michelle Naidoo Habib Zahir Rada Kostadinova Natalia Fernandez Alvaro Sponza San Shairzai Funding: Grant 001001-20122012-L’OrealL’Oreal-CONCYTEC 2013-BMCC Faculty Development 2013Grant CSTEP, PRISM and LSAMP programs