The study aimed at color removal and COD degradation of synthetic wastewater of methylene blue dye via photocatalysis using various spinel catalysts prepared by different methods. The methylene blue dye with strong azo bond with structure made up of autochrome and chromophore. The Azo dyes are widely used in textile, paper and leather industries. The present study is essentially related to the degradation of selected methylene blue and dye from synthetic dye wastewater however it has been extended to actual industrial effluents. In order to control wastewater pollution due to dyes the UV-Photocatalytic degradation technology has been carried out by some researchers using spinel catalysts. Spinel catalysts are oxides with general formula AB2O4 where A and B are the rare earth, A has octahedral site and B has tetrahedral site. alkaline earth, alkali metals and transition metal cations which are expected to be able to overcome the limitations of semiconductors as photocatalysts.

1. Project on
Synthesis of Spinel based Catalysts by Wet
chemical methods for Colour Removal from
Dyes Waste water
Presented By
Gandhi Yash (160170105017) Meda Sanjay (160170105027)
Patel Parth (160170105040) Rana Pranav(160170105046)
Guide by :
Dr. Femina Patel
CHEMICAL ENGINEERING DEPARTMENT
Year 2019-20 1

2. Contents
Industrial Effluents
Limits of Discharge of effluents from Industry
Current Treatments
Objectives
Literature Survey
•Materials and experiment methods
Summary and Conclusions
References
2

3. Industrial effluents
• Water resources contaminated by various industrial
activities
• Responsible industries are textile, paper, plastic, cosmetic,
dye and pigments etc. (30 to 40 % dyes remains in effluent
with toxic compound)
• Industrial effluent rich in COD, BOD, TOC, dyes etc.
• Serious environmental and health problems generated
• Conventional techniques use to eliminate dyes are difficult
• In India the Water (Prevention and Control of Pollution) Act
was enhanced in the year 15 Oct 1974 to control and
prevent water pollution
• 11 CETPs near Ahmadabad and 33 in all over Gujarat
• Treatments has operational limitations
3

4. Limits of Discharge of effluent from Industry
4
Dye
Organic compound
AuxochromsChromophore
-N=N-
=C=O
=C=C=
-NO2
-NH3
-COOH
-OH
-SO3H
Parameters Discharge limit
pH 6.5-8.5
Temperature 45 ˚C
100 (Pt-Co)/Hazen
COD 250 (mg/L)
BOD 100 (mg/L)
Oil, Grease 10 (mg/L)
Fluoride 1.5 (mg/L)
Sulfide 2.0 (mg/L)
Cyanide 0.2 (mg/L)
TDS 5000 (mg/L)
Sulfates 1000 (mg/L)
Chlorides 600 (mg/L)
Colour

5. Man-made Colorants
• Textiles
• Rubber
• Plastic
• Leather
• Cosmetics
• Paper
• Photographic
Natural Colorants
• Aquatic plants etc.
5
Dyes are:
• Complex aromatic structure
• Very stable
• Difficult to biodegrade
Sources of the dyes

6. Processes
for dye
degradation
Physical
Chemical
Electrochemical
Advanced
Oxidation (AOPs)
Adsorption, Coagulation,
Filtration
Electrocoagulation,
Electrochemical oxidation
Fenton Reagent,
Photocatalysis
TiO2/UV, H2O2/UV, O3/UV
Oxidation process:
ozonation
Mixed culture
Pure culture
Activated sludge
8
Biological

7. Different Processes Used in Industry for dye degradation
Treatment methods Advantages Disadvantages
Physical Method
Membrane Separation Can decolorize all types of chemicals class dye Sludge generation, Expensive, High Pressure
Ion Exchange Operative with no loss of regeneration Not effective for dispense dyes
Adsorption Effective, high capacity
Regeneration expensive, ineffective against vat
and dispense dye
Electrolysis Varying degree of success in colour removal By product, not applied for full scale
Chemical Method
Oxidation Rapid and Proficient process High energy cost
Coagulation Simple, Economically feasible Sludge production
Biological Method
Aerobic
Rapid and efficient process, efficient breakdown of organic
pollutants
Large amount of electrical energy, excess sludge
production
Anaerobic More environmentally friendly Less efficient than aerobic

8. Advance Oxidation Process (AOP)
• Utilize the hydroxyl radical (·OH) for oxidation
• Advantages: (1) Fast reaction rates
(2) Non selective oxidation
• Complete mineralization of pollutants
8
Advance
Oxidation
Process
Photocatalysis Fenton Based Ozone based Electrochemical

9. AOPs Advantages Disadvantages
Fenton’s Reaction
No potential formation of
bromate by product
Iron sludge generation due to
combined flocculation of the
reagent and the organic
compounds
Photocatalysis Performance under solar
irradiation
If the catalyst is added as a
slurry, separation step is
required
H2O2/UV
Full scale drinking water
treatment system exists
Potential bromate by product
Advantages and disadvantages of Advanced oxidation Processes (AOPs)

10. Mechanism of Photocatalyst
10
Odour
Virus
Stain
Surface of the photocatalyst
Organic
compound
Electrons(+ and - )
H2O (moisture)
+
- - - - - - - - - - - - -
O2 O2- Super oxide anion
H2O OH
+ + + + + + + + + + + +
Decomposition and detoxify
Finally H2O and CO2
OH, O2- organic compound
Light energy
Due to catalyst property decomposition
-
+
Advantages of photocatalysis
• Low energy consumption
• Complete mineralization of
pollutants into harmless
product
• Oxidation is at or above
ambient condition
Types of Photocatalyst
• Semi conductor
• Spinel
• perovskite

11. Semiconductor Band gap (eV) Spinel Band gap (eV)
TiO2 3.0-3.2 ZnRh2O4 1.2
Diamond 5.4 CaFe2O4 1.9
WO3 2.7 MgFe2O4 2.18
ZnO 3.2 ZnFe2O4 1.92
SnO2 3.5 NiFe2O4 2.19
SrTiO3 3.4 CuFe2O4 1.32
11

12. 12
Semiconductor
Mixed metal oxide Spinel AB2O4
TiO2 , ZnO , Fe2O3, Cds, SnO2, CeO2
Photocatalyst
• 4% of solar energy
• Wide band gap >3 eV
• Active only in UV range
• Less O-2 and OH⋅ radical
• High dosage
• Separation problem
• Sludge disposal
• Expensive process
• ZnO corrode in H2O < 7 pH
• Largest portion of solar spectrum utilised
• Narrow band gap (<3 eV)
• UV and visible range
• Radical formation is rapid (OH⋅ and O-2)
• Time & dosage minimum
• Batch, continuous process at room temp.
• Cost efficient
• Good electrical & magnetic properties
• Easily separated from water and reused
• Takes O2 from free atmosphere
• Finally CO2 and H2O realised
AII = divalent cation
Eg: Ni, Mg, Zn, Mn, Fe
BIII = trivalent cation
Eg: Al, Ga, Ti
NiFe2O4, CoFe2O4, Fe3O4, ZnFe2O4, MgFe2O4, FeCr2O4

13. Objectives
The main objective is to develop Spinel based Catalyst for
Photocatalytic degradation of Dye.
The specific objectives are as follows:
• To synthesis of Spinel Based Catalyst (NiFe2O4) by co-precipitation
and Citrate methods
• To study degradation of Reactive dye via Photo-catalysis by using
Spinel Based Catalyst
• Investigation of suitability of Spinel Based Catalyst in order to screen
suitable catalyst preparation method
• To study the effect of operating parameters such as pH, initial dye
concentration, Dosage of catalyst
• Detailed characterization of suitable catalyst
13

14. Literature survey
Sr.
No.
Spinel/Other
catalyst
Targeted
Pollutant
Method
Characterization
Techniques
Experimental
condition
Results Reference
1 TiO2
Acid orange (AO7),
λmax=484 nm
TiO2/UV LC/MS
Lamp= Artificial UV-Light (30 Watt)
pH=2-10
Dye-5-100ppm, Dosage=0.5-2g/L
COD=72.41% in 2.5 h and
decolorization 79.58%.
Longer irradiation time
required
Bansal et al.,
2010
2 ZnO
Methylene Blue ,
λmax 665 nm
ZnO/UV UV, BET, SEM, FTIR
UV Lamp=14 W
Dosage =0.4 g, Temperature = 30 ̊C
pH = 7.0,
initial dye concentration = 50 mg/l,
Colour Removal 58 %, COD
Removal =24% ,time 2 h
Chakrabati et
al., 2004
3 ZnO
Eosin Y. A, λmax
516 nm
ZnO/UV UV, BET, SEM, FTIR
UV Lamp=14 W
Dosage =0.4 g, Temperature = 30 ̊C
pH = 7.0
initial dye concentration = 50 mg/l
Colour Removal 39 %, COD
Removal =8.1% ,time 2 h
Chakrabati et
al., 2004
4
ZnFe2O4 Methyl Orange
λmax=400 nm.
CP XRD
UV lamp =230 V
Dosage=0.2 g into 50 ml. Dye,
Dark =30min.
75% of methyl orange
decomposes within 60 min
of irradiation
Jadhav et al.,
2011
5 ZnFe2O4
Acid Red 88,
λmax =505 nm.
SG
XRD, SEM,
HRTEM, BET, FTIR,
pH = 3.2–10.7,
Temp. = 20–60 ̊C,
Dye = 200 mL. (10-56 mg/L)
MB dye decreased to 96.8%
Konicki et al.,
2013
6
MnFe2O4 Methyl Orange,
λmax =507nm
SG
XRD, SEM, BET,
TPR, XPS
Dosage=0.1g
Dye = 200 ml (30 mg in L)
Stirring =30 min
MO degradation efficiency
up to 98%.
Zhang et al.,
2013
14
Note:
(SG-sol-gel, CP-co-precipitation)

15. Sr. No.
Spinel/Other
catalyst
Targeted
Pollutant
Method
Characterization
Techniques
Experimental
condition
Results Reference
7
CuFe2O4 Acid Red 206,
λmax=513 nm
SG XRD, FT-IR, UV
pH = 4, 10, 2,
Mercury lamps.
Speed = 250 rpm
3h color removal
Bagheri et
al., 2013
8
NiFe2O4
Di-n-butyl phthalate SG XRD, BET, FTIR, XPS
Lamp=1.0-L global glass reactor, 25 °C,
pH=7.7,
Dosage=0.01 g,
Use=40 mLmin-1 ozone flow rate,
0.45μm filter paper.
100% removal after 60
min
Ren et al.,
2012
9 NiFe2O4
Reactive Blue 5
λmax=599 nm
MW=774.16 g/mol,
SG XRD, DTA, FT-IR,
pH = 1,
Temp. = 25 °C,
Dosage=50 mgl−1,
Time =10 min.
90% adsorption efficient,
reusable adsorbent
Khorsavi et
al., 2013
10 NiFe2O4 Reactive Blue HT XRD, TEM, SEM
Lamp=300W UV-visible lamp, Distance
between the lamp and test solution was
about 10 cm,
Temp. = 25 ̊C,
Dosage =0.20 g,
Solution=50 mL test
Seven cyclic tests
stable, and easy to
separate using an
external magnet 98.7%
decolorization ratio
Liu et al.,
2012
11 NiFe2O4
Brilliant Green,
λmax=623nm,
TOC
CP, MW XRD, FTIR
Lamp=Microwave,
Dye = 50 mL,
Dosage = 0.8%
Dye removal 97%, TOC
91% time 2.0 min
Zhang et al.,
2011
12
TiO2-ZnFe2O4 Methyl Red,Thymol
Blue, λmax=425 nm
CT, AC, HT
XRD, BET, TEM, UV,
DR-UV, EDAX
Lamp= UV radiation 450 W Xe arc, 100
cm3 pyrex glass, Vessel and lamp 8 W,
wavelength 253, ± 50 nm,
Dye=50 cm3 of 50 ppm,
Dosage =100 mg
Degradation of 90, 75,
64 and 60% in the 1st,
2nd, 3rd and 4th cycles
Hankare et
al., 2011
15
Note:
(SG-sol-gel, CP-co-precipitation, HT-hydrothermal, MW-Microwave, AC-auto combustion, CT-citrate)

16. Sr. No.
Spinel/Other
catalyst
Targeted
Pollutant
Method
Characterization
Techniques
Experimental
condition
Results Reference
13
CoFe2O4
and CoFe2O4/TiO2
Reactive Red 120 ,
λmax = 512 nm
CP XRD, TEM, SEM, UV
Lamp=150W tungsten halogen
lamp
(400 nm intensity),
Temp.=ambient,
Stirred= 45 min,
pH =6.0,
Stirring = 45 min
Synergetic enhancement in
the photocatalytic
degradation.
Satishkumar
et al., 2013a
14 ZnFe2O4/SrFe12O19
Methylene Blue
(MB),
λmax=420 nm
CP
FTIR, XRD, SEM,
BET, XPS, VSM, UV–
vis.
Lamp=500 W Xe, visible,
pH=Neutral
Degradation rate was still
morethan 70% when the
composite was reused for
four times
Xie et al.,
2013
15
CoCr2O4
and CoCr2O4/TiO2
Methylene Blue
(MB), λmax= 664
nm
Methyl Orange,
λmax= 464 nm
SG
XRD, SEM, TEM,
UV- vis.
Lamp=400W halogen lamp,
Stirring = 50 min,
Dosage =20 mg,
pH= Neutral
Molar ratio=7:10
MB and MO dye decreased
up to 91% & 82%
Shojaei et al.,
2013
16
CoFe2O4
and CoFe2O4/ZnO
Direct Blue 71 (azo
dye), λmax= 594 nm
CP
XRD, SEM, TEM,
UV-vis, TOC
analyzer.
Lamp=150W halogen lamp .
Stirring = 45 min.
Dosage =1.6 g/L.
pH= Neutral.
71% of TOC was removed
within 5 hours with 3 times
recycle.
Satishkumar
et al., 2013
16
Note:
(SG-sol-gel, CP-co-precipitation)

17. Various Synthesis method of photocatalyst
SynthesisMethods
Wet Chemical
Co-Precipitation
Sol-gel
Citrate
Dry Chemical Ceramic
17

18. (A) Co-precipitation method (CP) (B) Citrate method (CT)
18
Preparation method of Photocatalyst by Co-precipitation & Citrate method
Nitrate salts solution
pH = 10
Filtration
1M Na2CO3
drop wise addition
Precipitate ageing
for 30 min
Calcination at
700 0
C for 5 h
Catalyst
Drying at 110 0
C
over night
Crushing

19. Preparation of NiFe2O4 by Co-precipitation method
19
Cake after filtration
Nickle Nitrate Ferric Nitrate solution of solution of
nickel nitrate ferric nitrate
Precipitation formation by adding
1M Na2CO3 (pH=10)
Washing & filtration
Drying at 110 ⁰C
for 16 h
Calcined at 750 ⁰C
for 5 h
NiFe2O4
mixing of above two

20. Preparation of NiFe2O4 by Co-precipitation method
20
Cake after filtration
Nickle Nitrate Ferric Nitrate solution of solution of
nickel nitrate ferric nitrate
Precipitation formation by adding
1M NaOH (pH=10)
Washing & filtration
Drying at 110 ⁰C
for 16 h
Calcined at 750 ⁰C
for 5 h
NiFe2O4
mixing of above two

21. Preparation of catalyst NiFe2O4 by Citrate method
21
Gel after Heating
Nickle Nitrate Ferric Nitrate solution of solution of
nickel nitrate ferric nitrate
Adding Citric acidHeating at 80 ⁰C till Gel Formation
Drying at 110 ⁰C
for 16 h
mixing of above two
Calcined at 750 ⁰C
for 5 h Final catalyst

22. Photocatalytic degradation of dye
22
150 ppm solution
of RB-21
pH of the dye solution 1 gm NiFe2O4 Catalyst
Stirring in dark for 30
min.
Stirring in sunlight
Sample collected by every 30 min.

23. List of Experiments
Sr No. Catalyst Synthesis method Dye
Amount of
Solution (ml)
Concentration of
dye (ppm)
pH of
solution
Dose of
catalyst (gm)
Result
1 NiFe2O4
Co-Precipitation
(Na2CO3)
Methylene Blue 50 150 7 0.5 No result found in terms of colour
2 NiFe2O4
Co-Precipitation
(Na2CO3)
Methylene Blue 100 100 7 1 Slight colour change within 18 hrs.
3 NiFe2O4 Citrate Methylene Blue 100 100 7 1 No result found in terms of colour
4 NiFe2O4 Citrate Methylene Blue 100 100 4 1 No result found in terms of colour
5 NiFe2O4 Citrate Methylene Blue 100 100 10 1 No result found in terms of colour
6 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 100 7 1 No result found in terms of colour
7 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 100 4 1 No result found in terms of colour
8 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 100 10 1 No result found in terms of colour
9 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 50 10 0.5 No result found in terms of colour
10 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 50 4 0.5 No result found in terms of colour

24. Sr No. Catalyst Synthesis method Dye
Amount of
Solution (ml)
Concentration of dye
(ppm)
pH of
solution
Dose of
catalyst (gm)
Result
11 NiFe2O4
Co-Precipitation
(NaOH)
Methylene Blue 100 50 7 0.5 No result found in terms of colour
12 NiFe2O4 Citrate Magenta HB 100 100 7 0.5 No result found in terms of colour
13 NiFe2O4 Citrate Magenta HB 100 100 7 1 No result found in terms of colour
14 NiFe2O4 Citrate Magenta HB 100 100 4 1 No result found in terms of colour
15 NiFe2O4 Citrate Magenta HB 100 100 10 1 No result found in terms of colour
16 NiFe2O4
Co-Precipitation
(Na2CO3)
Magenta HB 100 100 7 1 No result found in terms of colour
17 NiFe2O4
Co-Precipitation
(Na2O3)
Magenta HB 100 100 3 1 No result found in terms of colour
18 NiFe2O4
Co-Precipitation
(Na2CO3)
Magenta HB 100 100 10 1 No result found in terms of colour
20 NiFe2O4 Citrate Methyl Orange 100 50 7 0.5 No result found in terms of colour
21 NiFe2O4 Citrate Methyl Orange 100 50 3 0.5 No result found in terms of colour
22 NiFe2O4 Citrate Methyl Orange 100 50 10 0.5 No result found in terms of colour

25. Sr No. Catalyst Synthesis method Dye
Amount of
Solution (ml)
Concentration of dye
(ppm)
pH of
solution
Dose of
catalyst (gm)
Result
23 NiFe2O4
Co-Precipitation
(Na2CO3)
Methyl Orange 100 50 7 1 No result found in terms of colour
24 NiFe2O4 Citrate
Reactive Turquoise Blue
21
100 100 7 1 No result found in terms of colour
25 NiFe2O4 Citrate
Reactive Turquoise Blue
21
100 100 10 1 No result found in terms of colour
26 NiFe2O4 Citrate
Reactive Turquoise Blue
21
100 100 4 1 No result found in terms of colour
27 NiFe2O4
Co-Precipitation
(Na2CO3)
Reactive Turquoise Blue
21
100 100 7 1 Slight colour change within 24 hrs.
28 NiFe2O4
Co-Precipitation
(Na2CO3)
Reactive Turquoise Blue
21
100
50 + 1 ml Hydrogen
peroxide
7 1 Yes , colour removed within 150 mins
29 NiFe2O4
Co-Precipitation
(Na2CO3)
Reactive Turquoise Blue
21
100
100 + 1 ml Hydrogen
peroxide
7 1 Yes , colour removed within 180 mins
30 NiFe2O4
Co-Precipitation
(Na2CO3)
Reactive Turquoise Blue
21
100
150+ 1 ml Hydrogen
peroxide
7 1 Yes , colour removed within 240 mins

26. Summary and Conclusions
• The reactive turquoise blue (RB21) dye was treated for degradation of
industrial wastewater using spinel catalyst
• Among all spinel catalyst prepared NiFe2O4 and ZnFe2O4 gain promising
result with synthetic dye and industrial wastewater degradation.
• Photocatalytic activity were optimized as stirring the sample, requirement
of sample, initial concentration of dye, pH 7, catalyst dosage, irradiation
time
• From the experiment we conclude that using spinel based catalyst
(NiFe2O4) 75-80 % color Remove and also 70 % COD Reduction in 240
min for initial dye concentration of 50 mg/L in proper sunlight

27. [1] Khaleel, Rana I., Norli Ismail, and Mahamad H. Ibrahim. "The impact of waste water treatments on seed germination and biochemical parameter of Abelmoschus esculentus L."
Procedia-Social and Behavioral Sciences 91 (2013): 453-460.
[2] Borhan, A. I., et al. "Photocatalytic activity of spinel ZnFe2− xCrxO4 nanoparticles on removal Orange I azo dye from aqueous solution." Journal of the Taiwan Institute of
Chemical Engineers 45.4 (2014): 1655-1660.
[3] Nassar, Mostafa Y., Ibrahim S. Ahmed, and Ihab Samir. "A novel synthetic route for magnesium aluminate (MgAl2O4) nanoparticles using sol–gel auto combustion method and
their photocatalytic properties." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 131 (2014): 329-334.
[4] Verma, Akshaya Kumar, Rajesh Roshan Dash, and Puspendu Bhunia. "A review on chemical coagulation/flocculation technologies for removal of colour from textile
wastewaters." Journal of environmental management 93.1 (2012): 154-168.
[5] Seow, Ta Wee, et al. "Review on wastewater treatment technologies." Int. J. Appl. Environ. Sci 11 (2016): 111-126
[6] https://gpcb.gujarat.gov.in/
[7] Bhukal, Santosh, S. Bansal, and Sonal Singhal. "Magnetic Mn substituted cobalt zinc ferrite systems: structural, electrical and magnetic properties and their role in photo catalytic
degradation of methyl orange azo dye." Physica B: Condensed Matter 445 (2014): 48-55.
[8] Martínez-Huitle, Carlos A., and Enric Brillas. "Decontamination of wastewaters containing synthetic organic dyes by electrochemical methods: a general review." Applied
Catalysis B: Environmental 87.3-4 (2009): 105-145.
[9] Robinson, Tim, et al. "Remediation of dyes in textile effluent: a critical review on current treatment technologies with a proposed alternative." Bioresource technology 77.3 (2001):
247-255.
[10] Zangeneh, H., et al. "Photocatalytic oxidation of organic dyes and pollutants in wastewater using different modified titanium dioxides: A comparative review." Journal of
Industrial and Engineering Chemistry 26 (2015): 1-36.
[11] Chatterjee, Debabrata, and Shimanti Dasgupta. "Visible light induced photocatalytic degradation of organic pollutants." Journal of Photochemistry and Photobiology C:
Photochemistry Reviews 6.2-3 (2005): 186-205.
[12] Casbeer, Erik, Virender K. Sharma, and Xiang-Zhong Li. "Synthesis and photocatalytic activity of ferrites under visible light: a review." Separation and Purification Technology
87 (2012): 1-14.
[13] Pardiwala, Julie, Femina Patel, and Sanjay Patel. "Use of Spinels to Overcome the Limitation of Semiconductors as a Photocatalyst for Degradation of Dyes from Industrial
Waste Water: A Review.“
[14] Rajasulochana, Perepi, and V. Preethy. "Comparison on efficiency of various techniques in treatment of waste and sewage water–A comprehensive review." Resource-Efficient
Technologies 2.4 (2016): 175-184.
[15] Sathishkumar, Panneerselvam, et al. "ZnO supported CoFe2O4 nanophotocatalysts for the mineralization of Direct Blue 71 in aqueous environments." Journal of hazardous
materials 252 (2013): 171-179.
[16] Ahmed, Mohammad Boshir, et al. "Progress in the biological and chemical treatment technologies for emerging contaminant removal from wastewater: a critical review." Journal
of hazardous materials 323 (2017): 274-298.
27
References

28. [17] Kalra, Shashank Singh, et al. "Advanced oxidation processes for treatment of textile and dye wastewater: a review." 2nd International conference on environmental science and
development. Vol. 4. IACSIT Press Singapore, 2011.
[18] Khosravi, Iman, et al. "Preparation of nanospinels NiMnxFe2− xO4 using sol–gel method and their applications on removal of azo dye from aqueous solutions." Materials
Chemistry and Physics 130.3 (2011): 1156-1161.
[19] Sharma, Rimi, and Sonal Singhal. "Structural, magnetic and electrical properties of zinc doped nickel ferrite and their application in photo catalytic degradation of methylene
blue." Physica B: Condensed Matter 414 (2013): 83-90.
[20] Bansal, Priti, Damanjit Singh, and Dhiraj Sud. "Photocatalytic degradation of azo dye in aqueous TiO2 suspension: Reaction pathway and identification of intermediates
products by LC/MS." Separation and purification technology 72.3 (2010): 357-365.
[21] Chakrabarti, Sampa, and Binay K. Dutta. "Photocatalytic degradation of model textile dyes in wastewater using ZnO as semiconductor catalyst." Journal of hazardous
materials 112.3 (2004): 269-278.
[22] Jadhav, S. D., et al. "Effect of sintering on photocatalytic degradation of methyl orange using zinc ferrite." Materials letters 65.2 (2011): 371-373.
[23] Konicki, Wojciech, et al. "Equilibrium and kinetic studies on acid dye Acid Red 88 adsorption by magnetic ZnFe2O4 spinel ferrite nanoparticles." Journal of colloid and interface
science 398 (2013): 152-160.
[24] Zhang, Linfeng, and Yuanxin Wu. "Sol-Gel synthesized magnetic MnFe2O4 spinel ferrite nanoparticles as novel catalyst for oxidative degradation of methyl orange." Journal of
Nanomaterials 2013 (2013): 2.
[25] BAGHERI, GH A., V. Ashayeri, and K. Mahanpoor. "Photocatalytic efficiency of CuFe2O4 for photodegradation of acid red 206." (2013): 111-115.
[26] Ren, Yueming, et al. "Magnetic porous ferrospinel NiFe2O4: a novel ozonation catalyst with strong catalytic property for degradation of di-n-butyl phthalate and convenient
separation from water." Journal of colloid and interface science 382.1 (2012): 90-96.
[27] Khosravi, Iman, and Melika Eftekhar. "Characterization and evaluation catalytic efficiency of NiFe2O4 nano spinel in removal of reactive dye from aqueous solution." Powder
technology 250 (2013): 147-153.
[28] Liu, Shou-Qing, et al. "Magnetic nickel ferrite as a heterogeneous photo-Fenton catalyst for the degradation of rhodamine B in the presence of oxalic acid." Chemical
engineering journal 203 (2012): 432-439.
[29] Zhang, Lei, et al. "Investigation on the degradation of brilliant green induced oxidation by NiFe2O4 under microwave irradiation." Chemical engineering journal 173.3 (2011): 737-
742.
[30] Hankare, P. P., et al. "Enhanced photocatalytic degradation of methyl red and thymol blue using titania–alumina–zinc ferrite nanocomposite." Applied Catalysis B:
Environmental 107.3-4 (2011): 333-339.
[31] Sathishkumar, Panneerselvam, et al. " CoFe2O4 /TiO2 nanocatalysts for the photocatalytic degradation of Reactive Red 120 in aqueous solutions in the presence and absence
of electron acceptors." Chemical engineering journal 220 (2013a): 302-310.
[32] Xie, Taiping, et al. "Magnetic composite ZnFe2O4/SrFe12O19: Preparation, characterization, and photocatalytic activity under visible light." Applied Surface Science 273 (2013):
684-691.
[33] Shojaei, Abdollah Fallah, Atefeh Roshan Tabari, and Mohammad Hassan Loghmani. "Normal spinel CoCr2O4 and CoCr2O4 /TiO2 nanocomposite as novel photocatalysts, for
degradation of dyes." Micro & Nano Letters 8.8 (2013): 426-431.
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29. Thank You