Removal of copper(II) by adsorption onto peanut hull carbon from water and copper plating industry wastewater

Chemosphere. Vol. 32, No. 4, pp. 169-189.

Pergamon

Copyright

0045-6535(95)00332-O

8

1996 Elsevier Science

OF COPPER(I1)

BY ADSORPTION

PEANUT

HULL CARBON

COPPER

PLATING

Bharathiar

WASTEWATER

Chemistry

Division

of Environmental

University,

in USA

Sciences

Coimbatore-641

Tamil Nadu, (Received

ONTO

and C. NAMASIVAYAMk

Environmental Department

$15.00+0.00

FROM WATER AND

INDUSTRY

K. PERIASAMY

046

INDIA

10 July 1995; accepted

30 October

1995)

ABSTRACT Activated

carbon

by-product,

prepared

has been

1

solution. applicability Quantitative

from peanut hull (PHC),

used for the adsorption

The adsorption

obeyed

of Lagergren removal

Langmuir

kinetic

model

suitability

of PHC for treating

also testea. activated

A comparative carbon

an agricultural

of Cu(I1) from adsorption

has also

(GAC)

aqueous The

investigated.

20 mg/L Cu(II)

in the pH range 4.0 to 10.0.

copper

plating

industry

wastewater

study with a coal based commercial showed

waste

isotherm.

been

of Cu(I1) from a solution containing

by 0.9 g PHC per litre was observed

that the adsorption

capacity

The was

granular (Q,)

of

PHC was 18 times larger than that of GAC. Key words

: Peanut

hull carbon, adsorption, Langmuir isotherm, kinetics.

copper(H),

INTRODUCTION Copper

is introduced

baths,

pulp-paper,

oral

administration

damage

and acute

*

to

Author

whom

into water-bodies

petroleum, of excess poisoning

from metal cleaning

refining and fertilizer quantity to human

all correspondence

of copper body.

and plating

industries’.

Prolonged

may result

It is toxic

should be addressed

769

Ltd

Printed in Great Britain. All rights reserved 0045-6535/96

REMOVAL

1996

in liver

to fish but

770

toxicity

depends

and organic

upon other parameters

compounds

limit for copper

frequently

for discharge

such as alkalinity,

present

2,3

The tolerence

waters

is 3.0 mg/L4

in water

into inland surface

pH, hardness

and in drinking water is 0.05 mg/L’. Conventional ion

methods

exchange

lo,

cementation’ * , 13 operation and biological

eletrochemical the removal activated

of Cu(I1) from aqueous

carbon

reports

have

cheaper

such as precipitation6-8,

and readily

agricultural

wastes2’,

capable

Ni(II)26

from

recently’ 5-l ‘.

of activated Removal

We have recently

effectively

aqueous

by

Many

carbon

from

of copper

reported

Cr(VI)23,

from aqueous solutions.

here deals with a comparative of Cu(I1)

of copper

bottom ash2’ and formaldehyde-polymerized

of removing

and Pb(II)27

have been used for

Removal

importance

on the development available materials 19

skins22 has been demonstrated. was

treatment14

solution.

has gained industrial

appeared

coagu1ation/floccu1ation9, 12 , complexation/sequestration

by

peanut

that the PHC

Hg(II)24

Cd(II)25,

The investigation

reported

study of PHC and GAC for the removal

solution

and from

a copper

plating

industry

wastewater. MATERIALS

AND

METHODS

: PHC was prepared

Adsorbent

as reported

of 0.575 mm (20-50 mesh ASTM) was used. M/s. Burbidges same

size.

Table

1.

company,

Bombay,

The characteristics All the chemicals

Batch

studies

from cooper

The GAC, obtained

India, was ground and sieved

used are of analytical

from BDH, E.Merck,

prepared

The particle

: A stock

reagent

size from

to the

of PHC and GAC are summarized

were obtained mode

before25.

grade

in and

SD’s and / or Ranbaxy. solution

sulphate rCuSOn.5Hq01

of 1000

mg/L

Cu(II)

in water containinr!

was

I .O mL

771

Table

1. Characteristics

of the Carbons

Parameter Bulk density, g/mL Porosity, % Moisture, % Ash, % Solubility in water, % Solubility in 0.25M HCl, % PH Decolourizing power, mg/g Phenol number Ion exchange ca acity, mequiv/g Surface area, m Y? /g Iron, % Ash analysis, SiO K2 c? CaO MgG ‘2’5 Na20 Fe203

of concentrated

Cu(I1).

and

nitric

to obtain

One hundred

was adjusted

samples

using

dilute

were agitated

in a reciprocating at

10,000

;GAC = Granular

acid to prevent standard

0.60 60.40 6.79 3.84 1.42 8.18 77.00 20.00 Nil 354.00 1.43

19.60 0.58 0.56 9.80 0.10 78.70 0.76

79.60 2.30 0.28 6.50 1.20 12.10 4.10

1.56

activated

hydrolysis.

solutions

carbon

The stock

containing

mL of Cu(II) solution

solution

10 to 25 mg/L of

of a desired

rpm

or 500 mg of GAC was nitric

and

acid or sodium

added.

concentration

The adsorbent Cu(I1) Effects

in

the

The pH was

hydroxide

at 180 rpm for a predetermined

shaker.

spectrophotometrically28. using

0.63 61.70 14.14 2.11 0.74 2.25 6.68 36.00 68.00 0.49 208.00 0.27

to pH 5.0 and taken in reagent bottles of 300 mL capacity

60 mg of PHC

adjusted

GAC

% :

PHC = Peanut hull carbon

was diluted

PHC

was separated

solutions.

period at 30+l°C by centriftrgation

centrifugate

of carbon

concentration

100 mL of 20 mg/L Cu(I1) and varying

amounts

The

was were

analysed studied

of carbon

from

772

10

to

180

Adsorption

mg

PHC

isotherm

concentrations effects

for

were

mL solution

studies

from

were

100

carried

1800

out with

mg

for

GAC.

different

initial The pH

of carbon.

studied using 30 mg of PHC or 500 mg of GAC and 100 of Cu(I1) with concentrations

in the solutions

correct

for any adsorption

experiments

to

of Cu(I1) and a fixed concentration

Sodium

adsorption

and

was estimated

were carried

ranging from 10 to 25 mg/L. using a flame photometer.

of Cu2+ and Na+ on the containers, out without adsorbent

of either by the container

and there was negligible

walls.

studies

experiments

with 20 mg/L Cu(I1) and 100 mg of PHC or 500 mg of

the copper-laden

distilled

water

carbon

samples

then agitated

diluted

were

out

as follows:

was separated

any unadsorbed

prepared

After

and gently

Cu(I1).

adsorption

washed

Several

acid of various

with

such spent

for both PHC and GAC.

with 100 mL of hydrochloric

They

were

strengths

for

of PHC or 7h in the case of GAC and the desorbed

was estimated

The copper

carbon

to remove

3h in the case copper

carried

control

Desorption

GAC,

were

To

by analysing

the acid solutions

plating industry wastewater

collected

from Mettur, India, was

to 5 times so that the initial concentration

comparable

with the one taken for aqueous

and GAC.

For pH effects,

as before.

of Cu(I1) obtained

solution

studies

is

with PHC

100 mL of the sample with 30 mg of PHC

or 500 mg of GAC was agitated

for 3h in the case of PHC or 7h in

the case of GAC.

on the effects

sample

In the studies

pH was adjusted

to 5.0 and agitated

of carbon

with different

dosage,

the

dosages

of

and the mean values

are

PHC for 3h or GAC for 7h. All experiments presented.

were carried

Maximum deviation

out in duplicate was 3.5%.

773

RESULTS Effects

of agitation

the effect The

AND DISCUSSION time and initial concentration

of agitation

removal

equilibrium

1 presents

time on the removal of Cu(I1) by PHC and GAC.

(mg Cu(II)/g

carbon)

increases

with

time

and

attains

at 120 min for PHC and 300 min for GAC for the initial

Cu(I1) concentrations time required

: Figure

of 10, 15 and 20 mg/L.

for maximum

times less than that required

removal

It shows that the contact

of Cu(I1) by PHC would

be 2.5

by GAC.

40 32 1 24 t

ifP

16

B

8

e iTI 3

0

g (3 b

3.2

2

2.4

A:PHC 20

40

60

80

100

120

I40

160

180

4.0

1.6 0.8

B:GAC 0 t (min)

Fig.

1.

Effect of agitation time on the adsorption of Cu(I1). Cu(I1) concentration : (0) 20mg/L, (0) 15 mg/L, (A) 10 mg/L; pH,5.0. A : PHC concentration, 0.6 g/L; B : GAC concentration, 5 .O g/L.

774 Adsorption

kinetics:

and GAC follows

The kinetics

of Cu(II)

first order rate expression

adsorption

on both PHC given by Lagergren 29 .

log10 (qe-q) = lOglOqe_ k ad t / 2.303 where

q and q,

are the amounts

of Cu(II)

(min) and at eq ui l’ 1b rium . time, respectively, of adsorption applicability

(l/min).

Linear

plots

(1)

adsorbed and k,d

of log10

(mg/g)

at time t

is the rate constant

(q,-q)

vs t show

of the above equation for both PHC and GAC (Fig.2).

>

G

20

40

60

80

the The

100

B:GAC

.l 0

60

120

180 240

300

t (min)

Fig. 2. Lagergren

plots for the adsorption of Cu(I1). Cu(I1) concentration : (0) 20mg/L, (0) 15 mg/L, (A) 10 mg/L; A : PHC; B : GAC

775

kad values 10’2,

3.52

calculated x

concentrations

lo’*

from the slopes of the plots for PHC are 3.26 x and

3.37

x

IO-*

l/min

for

of 10, 15 .and 20 mg/L, respectively;

values for GAC are : 0.92 x lo-*,

the

initial

Cu(I1)

the corresponding

0.92 x lo-* and 1.10 x lo-*

l/mm,

respectively. Effect of carbon as

a

function

quantitative mL solution,

concentration: of

removal

carbon

Figure 3 shows the removal

concentration.

is

clear

that

for

the

of Cu(II) from a solution of 20 mg/L Cu(II) in 100

a minimum

PHC concentration

the case of GAC, only 95% removal concentration

It

of Cu(II)

of 0.9 g/L is required.

is obtained

for a minimum

In GAC

of 13 g/L.

r

100

C

A : PHC

01

I

0.2

I

0.4

I

0.6

I

0.8

I

1.0

I

1.2

I

1.4

I

1.6

I

1.8

53 100 ,p

80 60 40

3

20 i

0

d I

2

I

4

Carbon

Fig. 3.

I

6

I

8

I

10

concentraction

I

12

I

14

I

16

I

18

(g/L)

Effect of carbon concentration on adsorption of Cu(I1). Cu(II) concentration, 20 mg/L; pH, 5.0; agitation time for PHC, 311; agitation time for GAC, 7h.

776

Adsorption

isotherm:

equilibrium

for both PHC and GAC29.

Ce/Qe= where

C,

adsorbed related The

The Langmuir isotherm was applied for adsorption

to adsorption

Langmuir

plots isotherm

correlation

capacity

of C,/q,

coefficients

respectively.

concentration

(mg/g)

and Q,

(mg/L),

for

are 0.9971

Q, and b, respectively,

is the amount

of adsorption,

show

both

qe

and b are Langmuir

and energy vs C,

model

(2)

(Ce/Qo)

is the equilibrium at equilibrium

linear

+

l/(Qob)

that

PHC

the

and

and 0.9980

respectively.

adsorption

GAC

(Fig.4).

for PHC

were determined

constants

obeys The

and GAC,

from the slopes

0.8 0.6 -

8

16

24

32

40

48

L

14r

6

2 4 ‘//1. ’

B:GAC

8

16 C,

Fig.4.

24

32

40

48

(mglL)

Langmuir plots of adsorption of Cu(I1). Cu(I1) concentration,20 to 80 mg/L; pH, S.O;agitation time, 24h; PHC concentration, 0.6 g/L; GAC concentration, 10.0 g/L.

777

and intercepts of carbon carbon

of the Langmuir plots and found to be 65.57 mg of Cu/g

and 0.38

L/mg

of Cu for PHC;

and 3.60

mg of Cu/g

and 0.28 L/mg of Cu for GAC. The ratio of the Q,

of

value

of

can be expressed

in

PHC to that of GAC works out to be 18.21. The essential terms

characteristics

of a dimensionless RL, which

parameter, Langmuir

constant

value indicates values

of Langmuir constant

separation

factor

or equilibrium

is defined

by RL = l/(l+bC,),

where

and Co is the

initial concentration

of CUE’.

the type of isotherm.

between

isotherm

0 (zero)

According

and 1 (one) indicate

to McKay favourable

b is the RL

et a13’,

RL

adsorption

RL

values were found to be between 0 (zero) and 1 (one) at all the studied concentrations Effects from

of Cu(I1) for both PHC and GAC.

of pH:

waters

alkali.

One of the conventional

is the precipitation

methods

of metals

of removing

as metal

hydroxides

from solution

Hence

comparision

precipitation

owing to solubility is

made

between

as metal hyroxide.

Effects

product

of metal hydroxides.

adsorption

on

carbon

of pH on adsorption

by PHC and GAC are shown in Figs. S&6, respectively, Cu(I1) concentrations. of Cu(I1)

by hydroxide

more

different

efficient

concentrations

Cu(I1) removal a maximum adsorbent, presence bound

using

This method has got limitations that metal can not be completely

removed

much

metals

precipitation. compared

Adsorption

to metal

of Cu(I1) studied

in the pH range

of adsorbent, to occur

of Cu(I1)

for different

Figure 7 shows the effect of pH ou the removal by both carbons

hydroxide

6.0 to

of metal hydroxide both adsorption

a4 pH > 5.4.

precipitation

in the pH range

by both carbons increases with increase

precipitation

and

10.0.

for

2.0 to 5.5.

in pH aud attains

In the

absence

of any

starts only at pH 5.4. and precipitation

At lower concentrations

is

processes

In the are

of Cu(I1) such

778

as 10 and

15 mg/L,

precipitation

adsorption

at pH > 5.4.

seems

to dominate

At higher concentrations

over

of Cu(II)

20 and 25 mg/L, precipitation

seems to dominate

> 5.4.

be due to the precipitate

adsorbent

This

might

probably

sites leading to a reduced

hydroxide such as

over adsorption blocking

at pH the

uptake by adsorption.

z80 $ L

60

g

40

c3 .$

20

PHC

0

123456789 Initial

Fig.

5.

pH

Effects of pH on removal of Cu(I1) by PHC; Cu(I1) concentration : (A) lOmg/L, (0) lSmg/L, (fl) 20mg/L, (v) 25mg/L; carbon concentration, 0.3 g/L; agitation time, 311.

100

r

80 5 E” 60 E! ” 40 E

$!

GAC

20 1 0 Initial

Fig. 6

pH

Effects of pH on removal of Cu(I1) by GAC; Cu(I1) concentration:(A) lOmg/L, (0) 15 mg /L, (u) 20 mg/L, (0) 25 mg/L; carbon concentration, 5.0 g/L; agitation time, 711.

779

Initial

Fig. 7.

Effects of precipitation. (0)

The influence

pH

15 mg/L, (I)

pH

on the removal Cu(I1) by Cu(I1) concentration; (A) 20 mg/L, (r) 25 mg/L.

of pH on Cu(I1) removal can be explained

an electrostatic

interaction

mode131.

Besides mixture reduced adsorbent

on the basis of

As the pH decreases,

the carbon exhibits an increasing positive characteristics. to be adsorbed,

hydroxide 10 mg/L,

Cu2+, IS . also positive,

the adsorption

the surface of

Since the species is not favoured.

this, H+ ions present at a higher concentration in the reaction 2+ ions for the adsorption sites resulting in the compete with Cu uptake surface

of Cu(I1). becomes

On the more

contrary,

and more

as pH increases negatively

charged

the and

therefore

the adsorption

of positively

charged Cu2+ and Cu(OH)+

species

is more favourable. The mechanism ion exchange

of adsorption model.

A pure carbon

polar, but in actual practice and C,O2)

of Cu(I1) may also be explained

are usually

surface

is considered

some carbon-oxygen

present,

which render

Since there is no satisfactory

method for determining

of the surface

quantitatively,

the above

surface

complexes

oxygen

hydrolyse

slightly

is relative 32-34.

water molecules CxOH22+

+ 20H-

(3)

CO,

+ x H20

-+

C(OH),+

+ x OH-

(4)

Cx02

+ H20

+

c,o2+

Na+, C,O

with H2SO4

and NaHC03,

and C,S03Na

to be present 27. Na+ in the above groups

The

(5)

+ 20H-

NaZ2+ ,CxS03H

polar.

as shown below:

-+

upon treatment

CO,

the polar character

+ 2H20

such as C,O

assumed

statement

(C,O,

C,O

Since the PHC is prepared groups

to be non-

complexes

the surface

based on

are also

are also exchanged

with H+ in the medium as follows: C,ONa+

+ H+

+

C,OH+

C,ONa+

+ 2H+

+

CxOH22+

+ Naf

(7)

+

CxOH22+

+ 2Na+

(8)

-+

C,S03H

CxONa22+ C,S03Na Figure

8 shows

concentrations obtained

+ H+ the

effect

time reactions

of initial

of Cu(I1) for PHC.

under conditions

to (9) contribute introduced

+ 2H+

The curve referred

pH at different to as blank was Reactions

in pH in the blank curve.

(6) to (9) lead to the release during the prepration

(9)

= 0 (zero). of Na+.

into PHC when it was washed with NaHC03

free H2SO4

(6)

+ Naf

pH on final

such that [Cu(II)]

to an increase

+ Na+

(3)

At the same

Excess

Nat

was

to neutralise any

of PHC (see Table 1).

When Cu(II)

781

is present increase

in solution,

its adsorption

will free

some H+ and the pH

will be lower than in the blank (Eqs. 10, 11, 14).

At the same

time Na+ will also be released according to reactions (12), (13) and (15).

8

6

7

0 Initial

Fig. 8.

8

9

10

pH

Effects of pH on final pH on adsorption of Cu(I1) by PHC. Cu(I1) concentration: (0) 10 mg/L, (0) 15 mg&, (0) 20 mg/L, (I) 25 mg/L; (A) blank [0 mg/L Cu(II)]; carbon concentration, 0.3 g/L; agitation, time, 3h. 2C,OH+

+ Cu2+

-+

(C,0)2Cu2+

+ 2H+

C,0H22+

+ Cu2+

+

C,0Cu2+

2C,ONa+

+ Cu2+

-+

(C,0)2Cu2+

-+

C,0Cu2+

+

(C,SO~)~CU

+ 2H+

(14)

+

(C,SO~)~CU

+ 2Na+

(15)

C,0Na22+ 2C,S03H 2C,S03Na

+ Cu2+ + Cu2+ + Cu2+

+ 2H+

(10)

+ 2Na’ + 2Na+

(11) (12) (13)

782 Tests performed

by agitating

30 mg PHC for 3h at an initial pH of 4.0

led to a sodium concentration

of 18 mg/L in the remaining

when the Cu(I1) concentration mg/L, the difference

in solution

between

the released

sodium

when the concentration indicates

that apart

Since

the details

commercial

was found to increase

from exchange

were also exchanged

as expected.

of Cu(I1) was increased

Cu(I1) ions, significant

from

of H + ions on the adsorbent

Na + ions which were present

with

in the adsorbent

with Cu(I1) ions. of manufacturing

and activation

into GAC. The observation

mechanism

processes

for the

to discuss

how Na+

for the effect of initial pH on

final pH for GAC was similar to PHC (Fig.9). that ion exchange

18 to 38 mg/L

from 0 to 25 mg/L. This

GAC are not known, it is not possible

was introduced

from 0 to 25

the final pH value of the test containing

Cu(I1) and that of blank increased, Also,

was increased

liquid. Also

is important

Hence

to adsorption

it can be said processes

for

both carbons. Desorption

studies:

adsorption

and

adsorbent.

Desorption

recover

Attempts

respectively.

85.0,

precious

metals

from

the mechanism

wastewaters

and

of the

were made to desorb Cu(I1) from the spent carbons

using HCl of various PHC were:

studies help elucidate

strengths.

100.0

and

The per cent recoveries

100.0 by 0.025,

0.05

In the case of GAC, the corresponding

and 0.10

that ion exchange

the adsorption

the effects

and confirms

that were shown in Figs. 5&6.

M HCl,

values were : 64.6,

90.8 and 100.0. This is further evidence mechanism

of Cu(I1) for

is involved

in

of pH on adsorption

783

8

6

GAC

0 Initial pH

Fig.

Tests

9.

Effects of pH on final pH on adsorption of Cu(I1) by GAC. Cu(I1) concentration: (0) 10 mg/L, (0) 15 mg /L, (0) 20 mg/L, (I) 25 mg/L; (A) blank [0 mg/L Cu(II)]; carbon concentration, 5.0 g/L; agitation time, 7h.

with

of copper presents GAC.

copper

plating

It is clear

industry

wastewater

wastewater:

of pH on the adsorption that

for

the

of carbon

maximum

of Cu(I1) removal

2. Figure

by PHC

of Cu(I1)

10

and from

over the pH range 5.0 to

PHC is more efficient than GAC. concentration

The characteristics

are shown in Table

both PHC and GAC are effective

10.0; however effect

industry

the effects

wastewater,

plating

Figure

11 presents

the

on the removal of Cu(I1) from wastewater.

784

Table

2. Characteristics

of copper

plating

industry

wastewater

2.12

PH Conductivity,

4.91

mS/cm

1430.00

Total solids, mg/L Total hardness

as CaC03,

840.00

mg/L

Turbidity,

NTU

49.00

Chloride,

mg/L

282.20

Sulphate,

mg/L

350.00

COD, mg/L

61.57

Iron, mg/L

2.50

Copper,

98.00

mg/L

Nickel, mg/L

11.80

Sodium,

64.00

mg/L

Potassium, Calcium

6.00

mg/L as CaC03,

Magnesium

80.00

mg/L

as CaC03,

760.00

mg/L

r

100

8Oc

3

@ F G :

60 40 20 0 Initial

Fig.

10. Effects

pH

of pH on removal of Cu(I1) from copper plating industry wastewater. Cu(I1) concentration, 19.6 mg/L; (0) PHC concentration, 0.3 g/L; agitation time, 3h. (0) GAC concentration 5.0 g/L; agitation time, 7h.

785

0.2

E

60

0.4

0.6

0.8

1.0

1.2

1.4

1.6

I8

12

14

16

18

t

!!I: Carbon

concentration

(g/L)

Fig. 11. Effects

of carbon concentration on adsorption of Cu(I1) from copper plating industry wastewater. pH, 5.0; Cu(I1) concentration, 19.6 mg/L; (0): PHC, agitation time, 3h; (0) : GAC, agitation time, 7h.

For the quantitative 19.6 mg/L Cu(II), However,

removal of Cu(I1) from 100 mL wastewater a minimum PHC concentration

required.

This indicates

GAC

the

for

Applying

of 1.7 g/L is required.

in the case GAC, for the maximum removal

from 100 mL wastewater,

removal

Langmuir

that PHC is much more effective

isotherm,

for a Cu(I1) concentration

of Cu(I1) (43%)

a minimum GAC concentration

of Cu(I1)

from

plating

containing

industry

the per cent Cu(I1) removal

of 15.0 g/L is compared

to

wastewater. would be 95.6

of 19.6 mg/L and a PHC concentration

of

786 1.0 g/L,

whereas

Fig.11

observed

for GAC as well.

be due

to the

presence.

shows

82.1%

The decrease of other

removal.

The

same

trend

in the per cent removal

competing

ions

in the

is

might

industrial

wastewater. CONCLUSION The present adsorbent

investigation

shows that peanut

for the removal

The adsorption

capacity

that of a commercial

and recovery

hull carbon

is an effective

of Cu(11) from aqueous

solutions.

of peanut hull carbon (65.6 mg/g) is greater than

granular activated

to be operative

carbon (3.6 mg/g). Ion exchange

mechanism

seems

carbons.

As the

byproduct,

PHC may be useful for the economic

containing

Cu(I1).

adsorbent

in the adsorption

is derived

from

of Cu(II)

by both

an agricultural

waste

treatment

of wastewater

ACKNOWLEDGEMENT One of the authors Institute

(K.P.) is grateful

of Road and Transport

for providing

facilities

to Dr. M. Shanmugam,

Technology,

Erode,

Principal,

Tamil Nadu,

India,

and encouragement.

REFERENCES 1.

N.J. Shell, Industrial Pollution Control: Issue and Techniques, Van Nastrand Reinhold Company, New York, p. 177 (1981).

2.

of Cu(I1) R.C. Viashya and S.C. Prasad, “Adsorption dust”, Indian J. Environ. Protection, 11, 284-289 (1991).

3.

L. Hodges, Environmental Pollution, Windston, U.S.A., p.10 (1977).

4.

ISI, Tolerence limits for industrial effluents prescribed Standards Institution, IS: 2490 (part I) (1982).

on saw

2nd edn. Holt, Rinehart

and

by Indian

787

5.

ISI, Drinking

6.

J.G. Dean, F.L. Bosqui and K.H. Lanouette, “ Removing Heavy Metals from Wastewater “, Environ. Sci. Technol., 6, 5 18 - 522 (1972).

7.

D. Bhattacharyya, A.B. Jumawan and R.B. Grieves, “Separation of Toxic Heavy Metals by Sulphide Precipitation”, Sep. Sci. Technol., 14, 441 - 452 (1979).

8.

for B.M. Kim and P.A. Amodeo, “Calcium sulphide Process Treatment of Metal Containing Wastes”, Environ. Prog., 2, 175 180 (1983).

9.

R. Nilsson, “Removal Municipal Wastewater”.

water specification,

IS: 10500 (1991).

of Metals by Chemical Treatment Water Res., 5, 51 - 61 (197 1).

of

10.

EPA, “Summary Report : Control and Treatment Techmrology for the Metal Finishing Industry; Ion exchange”, EPA, 625/8-81-007 (1981).

11.

J.W. Patterson and W.A. Jancuk, “Cementation Treatment Proc. 32nd Purdue Industrial Co& Copper in Wastewater”. 853 - 865 (1977).

12.

T.L. O’Neill, G.R. Fisette and E.E. Lindsey, “Seperation of Metal Ions from Water by Chelation and Ultrafiltration” : Part A. AIChE Symposium Series, Water, 71, 100 - 104 (1975).

13.

P.L. Bishop and R.A. Breton, “ Treatment of Electroless Copper Plating Wastes”, Proc. 38th Purdue Industrial Waste Conf., 38, 473 - 480 (1983).

14.

E.Q. Moulton, and K.S. Shumate, “The Physical and Biological Effects of Copper on Aerobic Biological Waste Treatment Process”, Proc. 18th Purdue Industrial Waste Conf., 18, 602 615 (1963).

15.

A.P. Netzer and J.D. Norman, “Removal of Trace Metals Activated Carbon”, Water Pollut. Res. (Canada), 9 (1974).

of 32,

by

788

16.

I. Saito, “ Removal of Heavy Metals from Aqueous solutions using Sulphonated Coal and Activated Carbon”, Chem. Abstr, 86: 60134 g (1977).

17.

M. Jevtitch and D. Bhattacharyya, “Separation of Heavy Metal Chelates by Activated Carbon”. Chem. Eng. Commun., 23, 191 213 (1983).

18.

R.H. Moore, “Investigation of a Process for Removal of Copper from Seawater Desalination Plant Using Carbon Sorbates”, US. Dept. Interior, Report No. 651 (1971).

19.

J. W. Hassler, Purification with Activated Carbon, Publishing Co. Inc.: New York, NY, p. 169 (1974).

20.

P.A. Latif and N. Jaafar, “Adsorption by Selected Agricultural Wastes”, (1989).

21

A. Kaur, A.K. Malik, N.Verma and A.L.J. Rao, “Removal of Copper and Lead from Wastewater by Adsorption on Bottom Ash”, Indian J. Environ. Protection, 11, 433 - 435 (1991).

22.

J.M. Randall, Earl Hautala and Gary McDonald, “Binding of Heavy Metal Ions by Formaldehyde - Polymerized Peanut Skins”, J. Appi. Polym. Sci.,, 22, 379 - 387 (1978).

23.

K. Periasamy, K. Srinivasan and P.K. Murugan, “Studies on Chromium (VI) Removal by Activated Ground nut Husk Carbon”, Indian J. Environ. Hlrh., 33, 433 - 439 (1991).

24.

C. Namasivayam and K. Periasamy, “Bicarbonate - treated Peanut Hull Carbon for Mercury(B) Removal from Aqueous Solution”, Water Rex, 27, 1663 - 1668 (1993).

25.

K. Periasamy and C. Namasivayam, “Process Development for Removal and Recovery of Cadmium from Wastewater by a Lowcost Adsorbent : Adsorption Rates and Equilibrium Studies”, Znd. Eng. Chem. Res., 33, 317 - 320 (1994).

26.

K. Periasamy and C. Namasivayam, “Removal of Ni(I1) from Aqueous Solution and Nickel Plating Industry Wastewater Using an Agricultural Waste: Peanut Hull”, Waste Management, 15, 63-68 (1995).

Chemical

of Cu(II), Zn(II) and Pb(I1) Pertanika, 12, 193 - 200

789

27.

K. Periasamy and C. Namasivayam, “Adsorption of Pb(I1) by Peanut Hull Carbon from Aqueous Solution”, Sep. Sci. Technol., 30, 2223-2237 (1995).

28.

Vogel’s Text Book of Quantitative Chemical Analysis, 5th Edn., Revised by G.H. Jeffery, J.Bassett, J. Mendham and R.C. Denney, ELBS, Longman, London, p. 689 (1991).

29.

C.Namasivayam and K. Ranganathan, “Waste Fe(III)/ Cr(II1) Sludge as Adsorbent for the Removal of Cr(V1) from Aqueous Solution and Chromium Plating Industry Wastewater”, Environ. Pollution, 82,255 - 261 (1993).

30.

G. McKay, H.S. Blair and J.R. Garden, “Adsorption of Dyes on Chitin. 1. Equilibrium Studies”, J. Appl. Polym. Sci., 27, 3043 3057 (1982).

31.

K. Bhattacharya and C. Venkobachar, “Removal of Cd(I1) by Activated Carbon Adsorption”, J. Environ. Eng. Div., AXE, 110, 110 - 122 (1984).

32.

C.P. Huang and F.B. Ostovic, “Removal of Cd(I1) by Activated J. Environ. Erg. Div., ASCE, 104, 863 Carbon Adsorption”, 878 (1978).

33.

M.K.N. Yenkie and G.S. Natarajan, “Adsoption Equilibrium Studies of some Aqueous Aromatic Pollutants on Granular Activated Carbon Samples”, Sep. Sci. Technol. 26, 661 - 674 (1991).

34.

D.C. Sharma and C.F. Forster, “A Preliminary Examination into of Hexavalent Chromium using Low-cost the Adsorption Adsorbent?‘, Bioresource Technol, 47, 257 - 264 (1994).