Bio-based Adsorbents: Potential Candidates

for Wastewater Treatment

BioResources Research GroupBioResources Research GroupFaculty of Science & TechnologyFaculty of Science & TechnologyUniversiti Kebangsaan MalaysiaUniversiti Kebangsaan Malaysia

BioResources Research GroupBioResources Research GroupFaculty of Science & TechnologyFaculty of Science & TechnologyUniversiti Kebangsaan MalaysiaUniversiti Kebangsaan Malaysia

Wastewater TreatmentWastewater Treatment

� Various methods/technologies: coagulation, chemical

oxidation, ozonation, nano-filtration, precipitation, ion-

exchange, etc.

� Adsorption: ability to separate a wide range of

chemical compounds, easy operational procedures,

and facilitation of recovery of costly organic and

inorganic materials. inorganic materials.

� Contaminants: Acids, bases, toxic organic and

inorganic dissolved solids and colors,

� Dye stuffs, heavy metals, and effluents.

� Activated carbon – used as adsorbent for centuries

(high surface area to volume ratio).

� Bio-based adsorbents – low cost, abundantly

available, regeneration/reuse.

Biomass Resources

• 35-40 % high fibres length

• Used for high-end composite products

KenafKenaf

• Fast growing plant (~3 mths to harvest, 3 meters tall)

• 20 ton dried stems per hectare

• Contains bast and core fibres.

• 60-65 % short fibres

• limited strength which goes as water absorbing materials and animal bedding

Kenaf

Bast

Core

Cocoa pod14.71 %

• Generally, 10 tons of CPH will be

generated to produce one ton of

dry cocoa beans

• Malaysian Cocoa Board, ~300,000

tons of cocoa beans were

Cocoa Pod Husk (CPH)Cocoa Pod Husk (CPH)

Seed10.93 %

tons of cocoa beans were

produced in 2010 ≈ 3,000,000 tons

of CPH.

• Utilized as animal feed and

renewable energy source by

combustion

Oil Palm Empty Fruit Bunch FibresOil Palm Empty Fruit Bunch Fibres

• Malaysia is one of the largest palm oil exporter

• ~20 million tons of empty fruit bunch (EFB) are

produced yearly.

• Traditionally used as boiler burning material, organic

fertilizer, composite board and packaging materials.

• Physical and chemical approaches

• Physical – Refining/ball milling

ModificationsModifications

Sajab, M.S., Chia, C.H., Zakaria, S., et al.. 2010. Removal of copper (II) ions from aqueous solution using alkaline-treated kenaf core fibres. Adsorption Science and Technology 28: 337-386

Calculated Equilibrium Constants for the Sorption of Cu(II) Ions Calculated Equilibrium Constants for the Sorption of Cu(II) Ions

onto onto Kenaf Kenaf Core Fibres at 20 Core Fibres at 20 ooCC

Sajab, M.S., Chia, C.H., Zakaria, S., et al.. 2010. Removal of copper (II) ions from aqueous solution using alkaline-treated kenaf core fibres. Adsorption Science and Technology 28: 337-386

Sajab, M.S., Chia, C.H., Zakaria, S., et al.. 2010. Removal of copper (II) ions from aqueous solution using alkaline-treated kenaf core fibres. Adsorption Science and Technology 28: 337-386

• Chemical approach – alkaline treatment

ModificationsModifications

• Chemical approaches – chemical modifications

ModificationsModifications

H3C COCHO

OHCOOH −∆H2O

OCOOH

H2N−(CH2CH2N)x −(CH2CH2NH)y −

CH2CH2NH2

Tertiary amines, 25%

Primary amines,

Secondary amines, 50%

OH OH OH OH OH

CA-TREATED

CH3C

HO COOCOOH

HO

COOH

OH OH OH OH OH

PEI-TREATED

amines, 25%

50%

Sajab, M.S., Chia, C.H., S. Zakaria, Mohd Jani, S., Ayob, M.K. Chee, K.L., Khiew, P.S., Chiu, W.S. 2011. Citric acid modified kenaf core fibres for removal of methylene blue from aqueous solution. Bioresource Technology 102: 7237-7243 Sajab, M.S., Chia, C.H., Zakaria, S., Khiew, P.S. 2013. Cationic and anionic modifications of oil palm empty fruit bunch fibres for the removal of dyes from aqueous solutions. Bioresource Technology 128: 571-577

• Chemical approach – chemical modifications

ModificationsModifications

0

50

100

150Z

eta

po

ten

tia

l (m

V)

EFB Raw

-150

-100

-50

0

2 4 6 8 10

Ze

ta p

ote

nti

al

(

pH

EFB-CA

EFB-PEI

Sajab, M.S., Chia, C.H., Zakaria, S., Khiew, P.S. 2013. Cationic and anionic modifications of oil palm empty fruit bunch fibres for the removal of dyes from aqueous solutions. Bioresource Technology 128: 571-577

(METHYLENE BLUE)(PHENOL RED)

Dye AdsorptionDye Adsorption

MB before &after adsorption

PR before &after adsorption

COMPARISONCOMPARISON

Adsorbent Temperature Langmuir model

(oC) Q0 b RL r2

MB adsorption

Kenaf-CA 20 103.1 0.022 0.0110 0.994

40 128.2 0.072 0.0350 0.999

60 131.6 0.101 0.0630 0.994

CPH-NaOH 20 173.3 0.118 0.0274 0.866

40 179.5 0.160 0.0204 0.88840 179.5 0.160 0.0204 0.888

60 181.8 0.279 0.0118 0.845

EFB-CA 20 68.6 0.062 0.0512 0.978

40 86.4 0.162 0.0202 0.995

60 103.1 0.103 0.0314 0.975

PR adsorption

EFB-PEI 20 108.7 0.025 0.1177 0.943

40 123.5 0.014 0.1934 0.955

60 158.7 0.061 0.0516 0.906

RegenerationRegeneration

60

80

100

120A

dso

rpti

on

ca

pa

city

(%

)

MB

PR

0

20

40

1st Cycle 2nd Cycle 3rd Cycle 4th Cycle 5th Cycle 6th Cycle 7th Cycle

Ad

sorp

tio

n c

ap

aci

ty (

%)

PR

Sajab, M.S., Chia, C.H., Zakaria, S., Khiew, P.S. 2013. Cationic and anionic modifications of oil palm empty fruit bunch fibres for the removal of dyes from aqueous solutions. Bioresource Technology 128: 571-577

FixedFixed--Bed Column AdsorptionBed Column Adsorption

Discolouration of POME

(a) POME, (b) EFB-PEI adsorbed POME, (c) Anaerobic-treated POME and (d) EFB-PEI adsorbed anaerobic POME.

Graphene Oxide (GO)

• Graphene, a one-atom-thick planar sheet of sp2-bonded carbon

atoms that are packed in honeycomb crystal lattice.

• Attracted massive amount of attention since its discovery at 2004.

• GO - chemically modified graphene with oxygen functionalized

groups such as epoxide, hydroxyl, carboxyl & carbonyl.

• Highly hydrophilic - well dispersed in solution for modification and • Highly hydrophilic - well dispersed in solution for modification and

applications

Magnetic Graphene OxideMagnetic Graphene Oxide

*Fast adsorption equilibrium

MB MB + GO

Regenerated Cellulose Containing Graphene OxideRegenerated Cellulose Containing Graphene Oxide

Cellulose dissolution and regeneration

Regenerated Cellulose MembraneRegenerated Cellulose Membrane

High

porous

structure

Antibacterial Regenerated Chitosan Beads

E. coli

S. aureus

S. aureus

Control CB-GOCB CB-AgGOCB-AgNP

E. coli

Antibacterial results (Spread plate)

Control CB-GOCB CB-AgGOCB-AgNP

Sample S. aureus E. coli

CB −ve effect −ve effect

CB-GO −ve effect −ve effect

CB-AgNP +ve inhibition +ve inhibition

CB-AgGO +ve inhibition +ve inhibition

Thank youThank you