Eu opean Summi on In e disciplina y Resea ch and De elopmen - An In e na ional Resea ch Con e ence
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DEGRADATION AND REMOVAL OF PAPER MILL DYE BASIC
ORANGE 2 BY ELECTROCHEMICAL TREATMENT METHOD
Spoo hi
DSIR App o ed Resea ch and De elopmen Cen e, Robus Ma e ials Technology P .
L d., NGEF Layou , Naga abha i, Bangalo e, Ka na aka, India
Ci e This A icle: Spoo hi. (No embe 2025). Deg ada ion and Remo al o Pape Mill
Dye Basic O ange 2 by Elec ochemical T ea men Me hod. In P oceedings o he
Eu opean Summi on In e disciplina y Resea ch and De elopmen (pp. 77-82). Pe ambalu , Tamil Nadu, India:
C ys al Pen Publica ion.
ISBN: 978-93-49435-80-3
Publishe Websi e: www.c ys alpen.in
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DOI:
Abs ac :
This s udy deals wi h he ea men o Pape Mill dye Basic O ange 2, by elec ochemical deg ada ion.
The g aphi e ca bon elec odes we e used as anode and ca hode. Du ing elec ochemical deg ada ion, he
ch omopo ic g oups and a oma ic ings we e des oyed. The expe imen al esul s indica ed ha ini ial pH,
cu en densi y and suppo ing elec oly es such as NaCl and Na2SO4 we e played an impo an ole in
deg ada ion o dye. The maximum colou emo al e iciency o 85% and o al o ganic compound (TOC) 93%
could be achie ed o dye, a pH 3, cu en densi y 340 A m-2, NaCl 2.5 g L-1. The esul s e ealed he sui abili y
o he p esen p ocess o he e ec i e deg ada ion o dye e luen s.
Key Wo ds: Ca bon Elec odes; Elec ochemical Deg ada ion; Elec oly e; TOC; Indus ial Dye
In oduc ion:
The pulp and pape indus y is one o he oldes indus ies in ou coun y. Va ie ies o pape s and
simila p oduc s a e now manu ac u ed in di e en mills h ough he coun y Pape is made by pulping wood,
bleaching his pulp and hen sp eading i ou in o shee s o make i in o pape . A a ious s ages o he p ocess,
chemicals a e used o gi e he pape pa icula p ope ies, such as he bleaching chemicals ha make pape
whi e. This was ewa e gene ally la ge quan i ies o suspended solids, i also, i also con ains conside able
amoun o COD and BOD. The gene a ed was ewa e s can be e y dange ous hey should be ea ed be o e
being discha ged in o en i onmen . [1-5].The ea men o dye e luen is di icul and ine ec i e wi h
con en ional biological p ocesses [6] and se e al physic-chemical me hods because many syn he ic dyes a e
e y s able o ligh , empe a u e and non-biodeg adable na u e o mos dyes [7]. In his con ex , elec ochemical
echniques a e conside ed o be powe ul means o he ea men o dyeing o was ewa e [8-10].
Elec ochemical me hod is mos eco- iendly, easy ope a ed me hod o e ec i e dye emo al [11]. G aphi e
elec odes we e used as anode and ca hode by many esea che s o he applica ion in o ganic oxida ion [12-13].
In he pas , g aphi e was equen ly used as anode o he elec ochemical deg ada ion o was ewa e as i is
ela i ely cheape and gi es sa is ac o y esul s [14]. The aim o his wo k was o es easibili y o
elec ochemical me hod o he deg ada ion o Basic dye, B illian G een using g aphi e ca bon elec ode.
Ma e ials and Me hods:
Expe imen al Pa :
Ma e ials:
The indus ial dye Basic O ange 2(CAS No. 532-82-1) was ob ained om Myso e Pape Mill Indus y,
Bhad a a hi, India. Chemicals used o he expe imen s we e o analy ical g ade eagen s ob ained om s d ine
chem-limi ed, Mumbai, India. Cylind ical ca bon elec odes (chemical composi ion: g aphi e ca bon+-coke:
85%andash15%) we e ob ained om Powe Cell Ba e y India Limi ed. A digi al DC powe supply (AESC: 30
V, 2A) was used as an elec ical sou ce. Double dis illed wa e was used o p epa e he desi ed concen a ion o
dye solu ions and he eagen s.
Ins umen a ion:
Elec ochemical Deg ada ion S udies:
G aphi e ca bon elec odes o 4.6 cm leng h and 0.8cm diame e we e used as anode and ca hode o
elec ochemical deg ada ion s udies. The e ec i e elec ode a ea was 11.97 cm2. The suppo ing elec oly e such
as NaCl was added o he elec olysis ime. The solu ion was kep unde agi a ion using magne ic s i e .
UV- is S udies:
A UV- is spec opho ome e (UV-2602) was employed o measu e he op ical densi y o dye solu ion
(λmax: 498 nm) be o e and a e elec olysis. The deg ada ion e iciency was calcula ed using he ela ion:
%E = ((Ai-A )/Ai) × 100 - (1)
Whe e Ai and A a e abso bance alues o dyes solu ions be o e and a e ea men wi h espec o hei λmax
espec i ely o Ai and A a e ini ial and inal COD alues o he dyes solu ions, espec i ely.
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pH and Conduc i i y Measu emen :
A wa e analyze (Sys onics, Model-371) was used o measu e he pH and conduc i i y o he dye
solu ion be o e and a e elec olysis unde di e en elec olysis condi ions.
Resul and Discussion:
In luence o Elec olysis Condi ions on Dye Deg ada ion:
E ec o Ini ial pH:
A signi ican di e ence in he ex en o deg ada ion was no ed when he concen a ion o NaCl was a 3
g L-1. The ini ial pH o he solu ion (3-11) was adjus ed using 1M H2SO4 o NaOH [15].The elec olysis was
ca ied ou a he cu en densi y o 85Am-2 o 60 min wi h a dye concen a ion o 50 mg L-1 a oom
empe a u e. F om he abso p ion spec al s udies i was con i med ha , he la ge dye molecules we e deg aded
in o simple subs i u ed a oma ic compounds. Howe e , he hypochlo i e can lead o pa ial mine aliza ion o
dyes [16] and deg ada ion e iciency o Basic O ange 2was ound 75% in acidic pH3 and a ini ial pH11 he
deg ada ion e iciency was ound o be 56% (Fig. 1).I indica ed ha he deg ada ion o dye in acidic solu ion is
highe han ha o in he basic media. The e o e he op imum pH3 was main ained in subsequen expe imen s.
E ec o Suppo ing Elec oly es:
F om Figu e 2, i can be obse ed ha , he addi ion o NaCl o he dye solu ion du ing elec olysis
inc eases he decolou isa ion e iciency o Basic O ange 2. F om his obse a ion i was concluded ha he
in oduc ion o NaCl as an elec oly e can enhance he deg ada ion e iciency and sho ens elec olysis ime,
which may be a ibu ed o he eac ion be ween he elec o gene a ed chlo ine and dye molecule. The possible
mechanism o elec ochemical deg ada ion is gi en bellow,
Anode eac ion: 2Clˉ → Cl2 + 2eˉ - (2)
Ca hode eac ion: 2H2O + 2eˉ → H2 + 2OHˉ - (3)
Bulk solu ion eac ion: Cl2 + H2O → HOCl + HCl - (4)
HOCl → H+ + OClˉ - (5)
The abo e mechanism was classi ied as indi ec elec o-oxida ion o pollu an . Inc ease in he concen a ion o
NaCl up o 2.5g L-1 accele a ed he decolou a ion a e, enabling deg ada ion o dye o he ex en o 58%
decolou isa ion e iciency o Basic O ange 2(Fig. 2).
Fu he inc ease in NaCl concen a ion (> 0.5g/L) he e was a sligh imp o emen in decolou isa ion
e iciency, and he e o e he op imal concen a ion o NaCl in successi e deg ada ion s udied was ixed a 2.5g
L-1. Mo eo e , he inc eased op imal concen a ion o NaCl esul s in a dec ease in ope a ing ol age a he
gi en cu en densi y 85 Am-2 (Fig. 3) [16].
Demons a es he e ec o Na2SO4 on he deg ada ion o dyes. The decolu isa ion e iciency was ound
o be lowe han ha o NaCl (Fig. 4). The highe decolu isa ion e iciency in p esence o NaCl is a ibu ed o
he gene a ion o mo e powe ull o oxidizing agen s such as Cl2, HOCl, and OCl-. The decolou isa ion on
p esence o Na2SO4 is a ibu ed o he gene a ion o pe sulpha e ions ha can oxidize o ganic dyes [16].
E ec o Cu en Densi y:
Cu en densi y is a e y impo an a iable in elec ochemical p ocess. Di e en cu en densi ies (85,
170, 255, 340 and 425A m-2) we e applied o he cell o in es iga e he in luence o cu en densi y on he
elec ochemical decolou a ion o Basic O ange 2 keeping NaCl concen a ion a 2.5g L-1, dye concen a ion a
50ppm (w/ ), pH 3. I can be ound ha decolou a ion and e iciencies inc eased (Fig. 5) wi h inc easing he
applied cu en densi y [17]. This is because o he inc eased oxidan such as: chlo ine/hypochlo i e, hyd oxyl
adicals a highe cu en densi ies. Up o a cu en o 340 Am-2, he decolou a ion e iciency o bo h he dyes
was inc eased almos linea ly.
A highe densi ies (>340Am-2) he decolou a ion e iciency was a ained almos cons an . Also he
ene gy consump ion was ound o be mo e a highe cu en densi ies wi h a subsequen s ipping o elec odes
[18].
Analysis o COD & TOC:
In he p esen s udy i can be seen ha he deg ada ion o Basic O ange 2 om hei aqueous solu ions
may p oceed by indi ec elec ochemical oxida ion a he han di ec elec ochemical p ocess. The maximum
TOC o 93% could be achie ed o he dyes a 2.5 g L-1 o NaCl concen a ion, cu en densi y 340 A m-2 a pH
3 o Basic O ange 2, espec i ely. The elec olysis was ca ied ou a a cu en densi y o 340 A m-2. A his
cu en densi y, Cl2gene a ed in he solu ion d i es he oxida ion p ocess. The Cl2 species is a powe ul
oxidizing agen capable o oxidizing he dyes u s. In he absence o chlo ide con aining elec oly es, he TOC
emo al and dye deg ada ion e iciency was e y low. The pe cen emo al o TOC ound o be inc eased wi h
inc ease in he concen a ion o NaCl. This con i med ha he elec o gene a ed chlo ine/hypochlo i e will play
an impo an ole in he elec ochemical deg ada ion p ocess o he dyes u s.
Elec ic Ene gy Consump ion:
The majo ope a ing cos is associa ed wi h he elec ical ene gy consump ion du ing elec ochemical
deg ada ion p ocess. As pe he esul s he minimum elec ical ene gy consump ion was 7.72 k W h m-3 o dye
Eu opean Summi on In e disciplina y Resea ch and De elopmen - An In e na ional Resea ch Con e ence
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a 340 A m-2cu en densi y. A highe cu en densi ies, he ene gy consump ion was ound o be inc eased,
which may be a ibu ed o he inc eased hyd ogen and oxygen e olu ion eac ions.
Conclusions:
In he p esen s udy he decolou isa ion o hepulp and pape mill dyes selec ed o he s udy namely,
Basic O ange 2 was ea ed o ind ou he elec ochemical decolou isa ion me hods. In his me hod he
expe imen al esul s we e ob ained, nea ly 100% decolou isa ion o dyes wi h less ime consuming and low
powe consump ion. In he op imal ope a ional elec oly ic condi ions (cu en densi y 340 Am-2, NaCl
concen a ion 2.5 g L-1,pH 3 o Basic O ange 2 ) in luences he deg ada ion o dyeing in e media es.
Acknowledgemen s:
The Au ho s a e g a e ul o UGC, New Delhi o he inancial suppo ex ended. Also g a e ul o
Ku empu Uni e si y, Powe Cell Ba e y India Limi ed, Myso e Pape Mill Indus y, Bhad a a hi, India o
hei suppo o ca y ou his wo k.
Re e ences:
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2. V. Sa a anan and T. R. S eek ishnan, “Bio-physico-chemical ea men o emo al o colou om
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Managemen , 2015, 158: 146-157.
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Elec ochemical Me hod on Ca bon Elec odes,”Indian Jou nal o Na u al Sciences, 2012, 10: 976-997.
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dye,”In e na ional Resea ch Jou nal o Pu e and Applied Chemis y, 2014, 4: 402-416.
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Tex ile E luen con aining Azo, Diazo and Reac i e Dyes,” P ocess biochemis y, 1995, 31: 435-442.
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was ewa e : A u u e pe spec i e”, Asian Jou nal o Wa e and En i onmen al Pollu ion, 2010.
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elec ochemical me hod,”Jou nal o En i onmen al Chemical Enginee ing, 20131: 975-980.
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Chemical Socie y, 2005, 2:238-243.
18. D. Rajkuma , B.J. Song and J. G. Kim, “Elec ochemical deg ada ion o Reac i e Blue 19 in chlo ide
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Dyes and Pigmen s,2007, 72:1-7.
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Figu es:
200 300 400 500 600 700 800
0
1
2
3
4
5
2 4 6 8 10 12
55
60
65
70
75
Declou isa ion (%)
pH
Abso bance
Wa eleng h (nm)
Ini ial
pH 3
pH 5
pH 7
pH 9
pH 11
Figu e 1: Abso p ion spec a o Basic O ange 2dye solu ion be o e a e elec olysis a di e en pH Elec olysis
condi ion: concen a ion o dye solu ion: 50ppm (w/ ), pH: 3, NaCl: 3g L-1, cu en densi y: 85 Am-2 Inse
plo s: e ec o pH on colou emo al o dye solu ion.
200 300 400 500 600 700 800
0
1
2
3
4
5
0.5 1.0 1.5 2.0 2.5 3.0
20
30
40
50
60
70
80
Decolou isa ion (%)
Elec oly e (g/L)
Abso bance
Wa eleng h (nm)
Ini ial
0.5 g/L
1.0 g/L
1.5 g/L
2.0 g/L
2.5 g/L
3.0 g/L
Figu e 2: Abso p ion spec a o Basic O ange 2 dye solu ion be o e and a e elec olysis o di e en
concen a ion o NaCl. Elec olysis condi ion: concen a ion o dye solu ion: 50 ppm (w/ ), pH: 3, cu en
densi y 85 Am-2, ime: 60 min. Inse plo e ec o NaCl concen a ion on colou emo al o dye solu ion.
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Figu e 3: In luence o suppo ing elec oly es concen a ion on applied ol age du ing elec olysis dye solu ion.
Elec olysis condi ion: concen a ion o dye solu ion: 50 ppm (w/ ), pH: 3, cu en densi y 85 Am-2
200 300 400 500 600 700 800
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Abso bance
Wa eleng h (nm)
Ini ial
0.5 g/L
1.0 g/L
1.5 g/L
2.0 g/L
2.5 g/L
3.0 g/L
Figu e 4: Abso p ion spec a o Basic O ange 2 dye solu ion be o e and a e elec olysis o di e en
concen a ion o Na2SO4. Elec olysis condi ion: concen a ion o dye solu ion: 50 ppm (w/ ), pH: 3, cu en
densi y 85 Am-2, ime: 60 min.
0.5 1.0 1.5 2.0 2.5 3.0
3.8
4.0
4.2
4.4
4.6
4.8
5.0
Vol age (V)
Elec oly e (g/L)
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85 170 255 340 425
70
75
80
85
90
Remo al o Colou (%)
Cu en densi y (A m-2)
Figu e 5: E ec o cu en densi ies on decolou isa ion and COD emo al e iciencies o dye Basic O ange 2.
Elec olysis condi ion: concen a ion o he dye solu ion: 50 ppm (w/ ), pH: 3, NaCl: 2.5 g L-1.
Table 1:
Cu en (A)
Cu en Densi y Am-2
Requi ed Time (min)
Ene gy Consump ion (k Wh m-3)
0.1
85
60
2.56
0. 2
170
50
4.36
0. 3
255
45
6.23
0. 4
340
40
7.72
0. 5
425
40
10.26
