Biosorption of commercial dyes by green seaweeds. It is effective and innovative method for controlling water pollution

3. Water pollution
Pollution due to Dye
Sources of Dyes: Effluent from cosmetics, printing, dyeing, food
colouring
and paper making industries.
Effects of dyes: Carcinogenic, Mutagenic, Chromosomal fractures
and
respiratory toxicity.
Conventional treatments of effluent for removal of
dyes
Coagulation & Flocculation : Simple economically feasible but high sludge
Biodegradation : Economically attractive, Publically acceptable but very slow
Adsorption on activated carbon : Expensive and ineffective against specific
dyes.
 Membrane separation - Reverse osmosis, Microfiltration, Nanofilration ,
Electro dialysis: High pressure, expensive & incapable to treat large
volume.
Ion exchange : Effective but costly.

4. “Biosorption is an innovative technology for the removal of toxic
metals and dyes from polluted water using inactive and dead
biomass”.
Dye entrapment is due to physico-chemical interactions with active groups
present on the cell wall.
Biosorbents:
Bacteria, Algae, Fungi, Yeast, Agricultural waste, Aquatic macrophytes , Crab & Egg
shell etc.

5. Ref- Veglio and Beolchini
(1997).
Metabolism dependent
Intra-cellular
accumulation
Metabolism dependent or
independent
Extra-cellular accumulation
Metabolism independent
Cell Surface adsorption
Biosorption Mechanism
Transport across
Cell membrane
Precipitation Ion Complexation Physical
Exchange
Adsorption

6. •To investigate the sorption capacity of selected
material in removal of Methylene Blue from aqueous
solution.
•To monitor the effect of pH,
contact time,
adsorbent dose,
initial concentration of
dye,
agitation speed,
on the uptake of dyes
Objectives

8. .
MATERIAL COLLECTION :
Collection sites - Malvan and Kunakeshwar (Sindhudurg District)
Algal species : SARGASSUM SPECIES

9. .
Algal Biomass Preparation:
Collect SARGASSUM SPECIES from Seashore
Bring in
Laboratory. Clean, Wash With water Dry it in
Shade
Grind dried algae in Grinder Sieve the algal
powder
through sieve Obtain Algal biomass with fine
particles
Dye solution Preparation:
Take 1gm Methylene Blue powder
Dissolve in one liter distilled water for Stock solution

10. Dye Solutions - Methylene Blue (M.B.),
pH range -1 to 12
Adsorbent dose - 50-500 mg
Shaker speed - 50-250 rpm (Remi Cis- 24BL)
Time of contact - 10-120 min.
Adsorbate concentration - 50-1000mg/L
Dye detection - UV-Visible Spectrophotometer
Temperature - 299± 2K
Biomass particle size - Fine

11. Shaker
Filtration
Filtrate
Dye solution
Biomass
Analysis

12.  Dye Removal percent = ( Ci - Ce) /Ci
x100
Where,
Ci is initial concentration of dye
(mg/L)
Ce is final concentration of dye
(mg/L)
The amount of dye adsorbed on to the
biosorbent was calculated from the difference
between the dye ion concentration in the
solution before and after the biosorption
process

13. Optimizationof physico-
chemical factors for
biosorption
• pH
• Agitation time
• Adsorbate concentration
• Adsorbent dose
•Agitation speed
Experimental work

14. 38.91
46.01
50.98
55.55
65.85
83.8 82.84 81.09 78.72 77.01
74.29
71.42
0
20
40
60
80
100
0 2 4 6 8 10 12 14
%
Removal
pH
Optimum pH-6

15. 29.91
54.42
59.12
63.66
67.7 69.9
83.89 83.86 83.88 83.84
0
20
40
60
80
100
0 20 40 60 80 100 120
%
Removal
time (min.)
Optimum agitation time - 60 min.

16. 72.81
83.89
76.54
72.36
69.73
64.93
62.13
54.67
44.89
31.43
25
35
45
55
65
75
85
95
0 200 400 600 800 1000
Removal
%
Initial Concentration(mg/L)
Optimum dye concentration- 100 mg/L

17. 52.81
83.82 83.8183.79 83.8 83.81 83.78 83.75
40
45
50
55
60
65
70
75
80
85
90
0 100 200 300 400 500 600
Removal
%
Biomass (mg)
Optimum adsorbent dose- 100mg

18. 45.29
51.33
59.45
72.25
73.68
81.52
83.82 83.82 83.82
45
55
65
75
85
95
25 75 125 175 225 275
%
Removal
agitation speed (rpm)
Optimum agitation speed -200rpm

19. Significant findings from the present
investigation
Biosorption of Methylene Blue :
Optimum pH- 6
Agitation time- one hour
Adsorbate concentration - 100mg/L
Agitation speed - 200 rpm.
Adsorbent dosage- 100mg.
Maximum removal %-83.6%

20. •Dye Removal by using the seaweeds is significant
(83.6%) .
•Dye adsorption occurred favourably within weakly acidic
to neutral pH in biosorbent.
•Maximum biosorption occurred within one hour.
•A biomass dose of 100mg was found sufficient for
maximum uptake of dye from 50 ml aqueous solution at a
concentration of 100 mg/L.
Conclusions