3. • The dye manufacturing industries are among the most water consuming industries, which produce
complex wastewater containing heavy metals, organic and inorganic pigments along with low
amounts of aliphatic and aromatic hydrocarbons (Barbosa et al., 2018; Rodrigues and Külzer,
2016).
• The wastewater from dye manufacturing contains non-biodegradable organics and is toxic due to
various chemicals used in the production (da Silva et al., 2016).
• Dye manufacturing wastewaters are generally characterized by high color and high
• chemical oxygen demand (COD) (Wu and Wang, 2012).
• Therefore, if not treated properly the discharge of these wastewaters affect the receiving
environment by preventing the penetration of sunlight, decreasing the dissolved oxygen level, and
inhibiting photosynthesis (Verma et al., 2012).
• Conventional biological and chemical treatment methods are insufficient in the treatment of dye
manufacturing wastewaters due to its complex structure (Akyol, 2012). Thus, advanced oxidation
processes (AOPs) should be applied to provide the conversion of pollutants to less toxic or non-
toxic forms (Deng and Zhao, 2015).
3
Introduction
4. Introduction
• Electro-Fenton process is a modification of conventional Fenton reaction by
means of in-situ electro generation of Fenton’s reagent.
• EF process is an advanced oxidation process that is able to mineralize
organic pollutants such as
• pharmaceuticals,
• pesticides,
• dyes
• phenols, and phenol compounds
4
Introduction
5. Why Electro Fenton
• Application of EF process in wastewater can enhance
biodegradability and reduce toxicity (Nidheesh et al., 2021a; Babu et
al., 2019).
• Continuous formation of •OH without accumulation of Fenton's
reagent.
• Leaving no residue.
• Lack of toxicity of the reagents
• Electricity as a clean energy source is used in the process.
• Overall process does not create secondary pollutants.
5
Why Electro Fenton
8. Electrocoagulation
• Electrocoagulation process involves oxidation and reduction reaction in which destabilization
of contaminants (suspended, emulsified, or dissolved) happens because of application of
electric current to the electrolytic solution.
• EC unit consists of an electrolytic cell and metal (Al or Fe) electrodes which are connected to
an external power supply. The conductive metal plates are well known as sacrificial electrodes‘
which are made up of same or completely different materials as anode or cathode.
• In the EC process, anodic dissolution generates in situ coagulants along with hydroxyl ions and
hydrogen gas at the cathode.
• These in situ coagulants cause the formation of flocs within the sort of metal (Al or Fe)
hydroxides and/or poly hydroxides. The hydrogen gas generated at the cathode brings flocs at
the water surface by providing further buoyancy.
(M* Bharath,et al.,2018)
8
Electrocoagulation
9. Why EF+EC Combination
Reason Explanation
Enhanced Efficiency
Combining multiple treatment mechanisms increases the
overall efficiency of pollutant removal.
Broader Applicability
Hybrid processes can address a wider range of pollutants,
making them versatile for different effluents.
Complete Degradation
Ensures the breakdown of complex pollutants into simpler,
less harmful byproducts.
Reduced Energy Consumption
Energy consumption can be optimized, as some oxidation
reactions can proceed without external power input.
Removal of COD Color and Odor
Effective in removing COD, color and odor from textile
wastewater.
Minimized Sludge Production
Minimizes the production of sludge, reducing disposal
costs and environmental impact.
pH Adjustment
Allows for pH control within the desired range, optimizing
treatment efficiency.
Flexibility
Can be tailored to meet specific treatment goals and
regulatory requirements.
Why EF+EC Combination
10. EF + EC and EC + EF Why EF+EC better choice
• EF + EC and EC + EF processes have similar treatment efficiency.
• Alkali modified laterite soil was used as a heterogeneous EF catalyst and found
superior performance than the raw laterite soil.
• Laterite soil modified by an alkaline treatment was found to improve the surface
properties, as well as the EF activity.
• In EF process A total of 54.57% COD removal was observed after 60 min of the EF
treatment.
• Further treatment was carried out with EC process at different voltages. A total of
85.27%
• COD removal after 2 h treatment was observed by combining two electrochemical
processes. (Nidheesh et al.,2022)
10
12. Literature Review
Effluent Electrodes used Operating condition Pollutant reduction
(%)
Reference
Pharmaceuticals Cathode- carbon fibre
Anode- stainless steel
Current density -
0.45mA/cm2,
Voltage-1.8v
pH – 3
COD - 85%
Colour - 88%
Blenda ramirez, pereda
Alberto alvarez gallegos et
al 2020
Two parallel plates (ferrous
electrode used)
Current density- 58.47
mA/cm2,
pH- 2.89,
Volume ratio – 32 ml/L
COD – 97.21% Davarnejad & Meysam
Sabzehei et al 2018
Four iron plates pH – 2.99,
Current – 3.93 A,
Reaction time – 35.3
minutes
Removal efficiency
Cephalexine – 99.12 %,
Ciprofloxacine – 98.65%,
Clarithromycin – 99.38%
Irfan Basturk, Gamze
Varank et al 2020
Literature Review
13. Literature Review
EFP for Medical waste
water
Four parallel iron plates Current –3A,
pH – 3.4,
Reaction Time – 33.9
minutes
COD – 53.4%
BOD – 41.2%
Toxicity removal – 99.5%
Irfan basturk 2020
EFP
Synthetic waste
Graphite plates Current density –
0.55mA/cm2,
pH – 3,
Time – 20 minutes
Fe2 Concentration –
2mg/l
Colour – 89%
COD – 93%
TOC – 58%
Ayse kuleyin et .al 2020
EFP for textile
wastewater
Ti/RuO2 Current density – 0.32A,
Time – 90minutes
Ferrous sulphate
Concentration –
0.53mg/l
pH - 6
COD – 100%
Colour – 90.3%
P. Kaur , v.k sangal et. al
2018
13
Literature Review
14. Literature Review
SI.No Waste Water Electrods
used
Optimum conditions Removal
efficiency
Reference
1 Tannery WW Al pH;4-7
Retention time;360min
Current density=400A/m2
COD = 81%
CHROMIUM= 95%
Elabbas et
al.2016
2 Palm oil mill effluent Al pH;4.5
Retention time;65min
Current density=560A/m2
COD =75.4% Bashir et al.2016
3 Synthetic WW Al pH;10
Retention time;68min
Voltage=17 V
Nitrate = 87.95% Emamjomeh et al
2017
4 Domestic WW Al pH;6
Retention time;25min
Current density=1.65A
Turbidity = 98%
color =92%
Bracher et al
2020
14
Literature Review
15. Literature Review
Treatment process Cell configuration
(Anode/Cathode)
Wastewater type Maximum
mineralization
efficiency, %
Reference
EC-EF Cu/Cu/−BDD / Cu Oil and grease industry 99 8
EC Fe/Fe, Al/Al Paint manufacturing 93,94 9
EC Fe/Fe, Al/Al Textile 76,65 10
EC-PC Fe/Fe- Fe/Fe Various chemical and
textile industries
77 11
EC-O3 Fe/Fe Tannery plastics and
textile industries
60 12
EC-H2O2 Al/Al Plastics industry 90 13
EC-AO Fe/Fe-BDD / Fe Textile industry 99 14
c Boron-doped diamond(anode); d Peroxi-coagulation; EC-Anode BDD and,cathode- carbon felt
cathode e Anodic oxidation
(Hanane Afanga ,et al. 2020)
Literature Review
16. Literature Review
Process pH Electrolysis time
(min)
SEEC (kWh kg− 1) %COD Iron
consumption
(gdm− 3
EC 6 280 3.16 80 1.700
ECSA 6 280 2.33 97 1.399
EF 3 280 3.33 85 1.780
EFSA 3 280 3.67 92 2.064
(Louhichi et al .,2022)
16
Literature Review
17. Literature Review
All the processes sufficiently removed color from the wastewater in as much as between 77% and 94%
decolorization efficiency was gained.
(ECF, EF and PC) enhanced BOD5/COD ratio from 0.137 to over 0.3 while EC process could not increase BOD5/COD
ratio significantly.
BOD/COD ratio of textile wastewater is in the range of 0.1–0.25 indicating existence of non-biodegradable organic
compounds such as dyes in textile wastewater. Therefore, it is essential to find an efficient method of
wastewater treatment for color and toxic organic compounds removals from textile effluents.
The BOD5/COD index is usually used for the assessment of physicochemical processes as a pretreatment before
the biological processes
(Ghanbari et al.,2014)
17
Literature Review
18. Literature Review
0.137
0.178
0.341
0.362
0.317
0 0.1 0.2 0.3 0.4
Raw textile wastewater
Electro-coagulation
Electrochemical Fenton
Electro-Fenton
Peroxi-coagulation
Fig.BOD5/COD ratio after iron based electrochemical
processes treatment at optimum conditions
(Ghanbari et al.,2014)
Literature Review
19. Research Gap
Textile wastewater consists of huge amount of dissolve pollutants which can’t be
effectively treated by the coagulation process.
Conventional process are not sufficient to treat POPs and dissolve dyes.
19
Research Gap
20. Research Objectives
COD Removal
TOC Removal
Colour and Odour Removal
Improving Efficiency
Improving
Biodegradebility
Energy Consumption
Reduce Sludge production
Electrolysis time
Material Degradation
20
Research Objectives
22. Experimental plan
• The sample was
taken out after
treatment
• According to
• DOE.
pH adjustment For
EF 3 And For EC 6
using 0.1N HCl and
0.1N NaOH
Cooling of the
sample
Heating for 30 min
for homogenous
solution
Preparation of
synthetic textile
wastewater (stww)
EF and EC at
different operating
conditions
22
29. • We Have Finalized which Red Azo dye we will work on.
29
Work in Progress/Outcome
30. References
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processes. Water res. 2000;34:2253–2262.
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4. Cruz-Gonzalez K., Torres-Lopez O., Garcia-Leon A., Guzman-Mar J.L., Reyes L.H., Hernandez-
Ramirez A., Peralta-Hernandez J.M. Determination of optimum operating parameters for acid
yellow 36 decolorization by electro-Fenton process using BDD cathode. Chem. Eng. J.
2010;160:199–206.
30
References
31. References
5. Bocos E., Iglesias O., Pazos M., Sanroman M.A. Nickel foam a suitable alternative to increase the
generation of Fenton's reagents. Proc. Saf. Environ. 2016;101:34–44
6. Oturan N., Zhou M., Oturan M.A. Metomyl degradation by electro-Fenton and electro-Fenton like processes: a
kinetics study of the effect of the nature and concentration of some transition metal ions as catalyst. J. Phys.
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materials. Appl. Catal. B Environ. 2013;140–141:92– 97.
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32. References
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33
References
Editor's Notes
The external addition of iron source is very important for the production of hydroxyl radical in EF process. The addition of iron source to the EF process increases the COD removal efficiency due to the generation of strong oxidants, majorly hydroxyl radical ( • OH). The
anode oxidation, in which the metal cations (Al or Fe) are generated;
(2) water is electrolyzed in the cathode, producing small hydrogen bubbles and hydroxide;
(3) solution reactions, in which metal ions react with hydroxide to form hydroxy complexes, which adsorb the pollutants, form coagulants, and can then be separated by coagulation/flocculation processes
SA=with and without Sparging Air
Electrocoagulation process A pair of iron electrode was used as anode and cathode with distance of 2 cm. The electrodes were installed within the electrochemical cells. Electrochemical Fenton apparatus This process was carried out in a condition similar with that of the electrocoagulation which was merely different in adding H2O2 in various concentrations before the electrolysis. Electro-Fenton process The platinum sheet with dimensions of 10 25 mm was placed in the center of the cell as anode that was surrounded by graphite felt cathode covering the inner wall of cell. Before the electrolysis, 2 L/min compressed air was bubbled for 12 min to saturate the aqueous solution with O2. Different concentrations of Fe2+ were added to the solution to investigate the effect of catalyst. Peroxi-coagulation (PC) process PC was similar with the electro-Fenton process. An iron electrode was placed instead of platinum sheet as anode electrode. During the electrolysis, the solution pH was regulated to 2.8– 3.4 and 6.2–6.7 by either 0.1 M H2SO4 or 0.1 M NaOH every 12 min.
Persistent organic pollutants (POPs) are organic compounds that are resistant to degradation through chemical, biological, and photolytic processes.[1] They are toxic chemicals that adversely affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can and do affect people and wildlife far from where they are used and released.
