1. Nadirah binti Ismail
1st Assessment (2013/2014)
Supervisors:
Assoc. Prof Dr Zaiton Abdul Majid
Assoc. Prof Dr Zaharah Ibrahim
Chemistry Department
Faculty of Science,
Universiti Teknologi Malaysia

2. Proposed Title
Isotherm, Kinetics and Thermodynamic Studies
on Adsorption of Chlorpyrifos Using Modified
Ananas Comosus (Pineapple) Leaf Powder

3. Chlorpyrifos

4. 1 or more
aromatic ring
Persistent
Organic
Pollutants
Variable numbers
of halogen
substitutions
Lack of polar
functional groups

5. the spraying of pesticides into our
external space results in only 5%
of the pesticide reaching the target
pest. The rest runs off into water
and dissipates in the air.
Pesticide Movement
Active ingredients + wetting
agents, solvents, buffers, pres
ervatives & emulsifiers
1
photochemical degradation
3
weaken the ecosystem
damaging soil microbes
biodegradation
2

6. Methods for pesticides removal
Photodegradation
Membrane filtration
Ozone treatment
Combined Ozone and UV

7. Disadvantages of conventional
treatment
Cost
Pesticides not
removed during
physical treatment

8. Adsorption
• The binding of molecules or particles to a surface.
• Happens at the surface of the substance.
• Physical adsorption : forces of attraction between
the molecules are of the weak type. Can be easily
reversed by heating or decreasing the pressure
• Chemical adsorption :forces of attraction between
the molecules are very strong. Chemical bonds
present on the surface.

9. Lignocellulosic materials
Lignocellulose refers to plant
biomass. It is the most abundantly
available raw material on the
earth, It is composed of
carbohydrate polymers (cellulose
and hemicellulose) and an aromatic
polymer (lignin).

10. High C
Cellulose
A good
adsorbent for
pesticides
Good adsorbent
Lignin
Good adsorption
capacity
Develops
micropores
Develops
macropores
Dyes, pesticides, phen
ols, surfactant
Towards phenols and
nitrogen containing
compounds

11. Adsorption
• Physicochemical process.
• Enable microorganism communities to adsorb
some toxic materials from solutions.
• Allows it to passively concentrate and bind
contaminants onto its cellular structure.
• EPS in microbial aggregates have many available
sites for the adsorption. The adsorption of
organic pollutants by microbial aggregates may
be attributed to the fact that there are some
hydrophobic regions in EPS.

12. Problem Statement
• The application of PLP to adsorb pesticides
have not entered the scientific literature
extensively
• Adsorption is a difficult subject because
adsorption may occur via several different
mechanism.
• Understanding adsorptive interactions
between Chlorpyrifos, lignocellulosic material
(PLP) and biomass/biofilm

13. Hypothesis
• PLP that comprises of lignin, cellulose and
hemicelluloses embedded with immobilized
bacteria has the potential to remove
Chlorpyrifos from aqueous solution via several
adsorptive interactions.

14. Objectives of study

To characterize the lignocellulosic materials in PLP for adsorption of
Chlorpyrifos

To evaluate the adsorptive interaction of interaction between
chlorpyrifos with biofilm coated PLP

To determine the composition, thickness and efficiency of biofilm for
the removal of Chlorpyrifos

15. Significance of study
• Chlorpyrifos has been detected in unfiltered river water
sample taken from Sungai Sayong, Kulai, Johor.
• To solve the disposal problem of agricultural waste
• The adsorption behaviour of chlorpyrifos onto
lignocellulosic material is essential in predicting their
potential to be adsorbed or desorbed from the
adsorbent.
• Development of biofilm onto lignocellulosic material in
PLP will enhance the Chlorpyrifos removal and
degradation.

16. Novelty of study
• The adsorptive interaction of
Chlorpyrifos, lignocellulosic material, biofilm
in PLP has not been investigated in any
research.

18. Knowledge Gap
• Adsorbent
• Biodegradation
Organoclay
Calcium alginate +
Pseudomonas
Bacillus cereus
Enterobacter sp
Klebsiella sp
Serratia sp
Chlorpyrifos (None)
-Heavy Metal
-Hydrocarbon
-PAH
Dyes
• Biofilm

19. -Hydrolysis may occur at several
reactive centres in the pesticide
molecule, in the presence of
OH- or H2O acting as
nucleophilic reagents
*Cell membranes, many
classes of lipids and
lipoproteins, pesticide
accumulation
Gram negative, LPS
Chlorpyrifos
Sorption may occur through hydrogen
bonding from the hydroxyl surfaces
toward oxygen atoms in the organic
molecules.
carbonyl oxygen of the
carbon surface acting as
the electron donor and
the aromatic
ring of the adsorbate
acting as the acceptor.
hydroxyl groups on the
polymer surfaces, which
probably have a positive
effect on cell adherence.
Surface of
lignocellulosic material

20. FINDINGS

21. • Part 1: Preparation of adsorbent
Collection of pineapple leaves
Pre-treatment
Wash
Dry and sieve
Storage
Dessicator

22. Wash
Dry
Grind & Sieve
(d)
Pineapple leaf
Pineapple leaf powder

23. Chemical treatment of adsorbent
Rewash with
Deionized water
0.1M nitric
acid 1hour
Methanol
1hour
• Methanol to remove inorganic and organic
matter from the surface of sorbents.

24. • Part 2 : Characterization of adsorbent
1) Functional groups
Fourier Transform Infra Red Spectroscopy
2) Surface Area
Brunauer, Emmett and Teller
3) Elemental Analysis
C,H,N,S
4) Surface images
Field Emission Scanning Electron Microscope (FESEM)

25. SEM of raw & treated PLP
Lignocellulosic biomass has a
complex and rigid cell wall
structure which consists of three
principal biopolymers, namely
cellulose, hemicellulose, and
lignin.
Unmodified PLP
Rough inhomogeneous
surfaces have multiple sitetypes available for adsorption
Modified PLP

26. Fiber and elemental analysis
Parameter
Composition (%)
Cellulose
26.15
Hemicellulose
53.45
Lignin
6.93
Carbon
40.49
Hydrogen
6.45
Nitrogen
1.60
Sulfur
0.56
•Soft wood
• Carbonaceous material- suitable for adsorption

27. Surface area of PLP
• Surface area - 8.61m²/g *(Carbonaceous materials
10-15 m²/g)
Pore size - 5.948 Angstroms
(micropores)
• * micropores are directly accessible from the
external surface of the fiber. Thus, Chlorpyrifos
can reach adsorption sites through micropores.
May ease the adsorption process.

28. X-ray fluorescence
(XRF) of PLP
No
Parameter
Results (%)
1
Potassium Oxide
4.94
2
Calcium Oxide
2.60
3
Chlorine
1.66
4
Sulphur Trioxide
1.34
5
Magnesium Oxide
1.07
6
Silicon Dioxide
1.05
Inorganics and minerals
* it can block the porosity of the carbon matrix and can preferentially adsorb water due
to its hydrophilic character, in this case reducing the adsorption of the lipophilic
Chlorpyrifos.

29. Ash content of PLP
• Ash is the inorganic residue remaining after
the water and organic matter have been
removed by heating
• 8.7%
• Low ash content and have advantage in
preparing adsorbent with high specific surface
area

30. FTIR of raw PLP
Hydroxyl groups,
Presence of –OH
groups
Aromatics
groups in
lignin
Carbonyl group in
hemicellulose

31. FTIR of modified PLP
Presence of –OH groups. The acid
pre-treatment increases the concentration of
the hydroxyl groups on the support.
Carboxyl groups,

32. pH at zero point of charge of
modified PLP
(pH at which the net surface charge is = 0)
12
pH drift method
10
8
6
pH final
pH initial
4
At this value (7.2), the
adsorbent is neutral, while it
turns positively charged at
lower pH values or negatively
charged at higher pH values
2
0
0
2
4
6
8
10
12

33. Part 3 : Isolation, Screening and
Biofilm development
1) Isolation
Microclear, soil, cultured drink
2) Screening
Chlorpyrifos tolerance, degradation, removal
3) Biofilm developemnt & degradation
Biofilm thickness, biofilm composition, isotherm, kinetics, thermodynamic
4) Surface images
Field Emission Scanning Electron Microscope (FESEM)

34. Gantt Chart

35. Thank You

36. Proposed title
• Isotherm, kinetics and thermodynamic studies
on combined adsorption and biodegradation
of Chlorpyrifos using lignocellulosic material in
Ananas comosus (Pineapple) leaf powder.

37. • Pesticides ingredients:Active
ingredients
intended to kill
the target pest
Inert ingredients
used as bulk
carriers for
active
ingredients
PESTICIDES
• not really “inert” at all; they are actually more
toxic than the active ingredients.
• This inert information is usually not required
to be displayed on the product label by the
authorities.

39. Pineapple Leaf Powder
Optical & Phase Contrast Microscope
images

40. Reactive Red dye adsorbed
onto PLP
Reactive Black 5 dye adsorbed
onto PLP

41. SEM of raw & modified PLP
Unmodified PLP
Modified PLP

42. * Crystalline and amorphous
structures- XRD

43. Adsorbent Modification
(Biologically Inspired Design = Biomimetics)
• What? : Biomimetics is the study of the structure
and function of biological systems as models for
the design of materials. It is widely regarded as
being synonymous with biomimicry
• Why? : Pesticides can bioconcentrate: The
primary "sink" for some pesticides is fatty tissue
("lipids"). Some pesticides, such as DDT, are
"lipophilic", (fat loving) meaning that they are
soluble in, and accumulate in, fatty tissue such as
edible fish tissue and human fatty tissue.

44. Triolein -embedded PLP
composed of the supporting PLP and the surrounding trioleincellulose acetate membrane.
Pesticides / non polar NEPs
Triolein layer
PLP
CA = useful
polymer, used to
combine triolein
and PLP.
Triolein has a high
accumulating capacity
for trace lipophilic
chemicals. Naturally
found in fatty
tissues, cheap.
is a symmetrical
triglyceride
derived from
glycerol and
three units of the
oleic acid

45. Hydrophilic
membrane
structure
(polyamide)
Lindane
Dieldrin
Atrazine
Hydrophobic
nucleolus
(triolein)
Nitrobenzene

46. Chlorpyrifos degradation
The degradation pathway of chlorpyrifos in aquatic environments involves the
breakdown of the thiophosphoric esters, forming 3,5,6-trichloropyridinol (TCP) and
desethyl chlorpyrifos (DEC) as main metabolites.

47. FTIR
• The region to the right-hand side of the diagram (from
about 1500 to 500 cm-1) usually contains a very
complicated series of absorptions. These are mainly
due to all manner of bending vibrations within the
molecule. This is called the fingerprint region.
• It is much more difficult to pick out individual bonds in
this region than it is in the "cleaner" region at higher
wavenumbers. The importance of the fingerprint
region is that each different compound produces a
different pattern of troughs in this part of the
spectrum.

48. Lignin
macroporous
structure
Cellulose
microporous
materials
Lignocellulosic

49. Cellulose

50. Lignin

51. Adsorption kinetics
• The rate of adsorption of a molecule onto a
surface

52. Adsorption isotherm
• For a better understanding of binding
mechanism of the sorption system, between
liquid and solid
• Langmuir adsorption isotherm is based on the
following assumptions.
• i) Adsorption is a monolayer coverage.
• ii) All the sites available on the adsorbent
surface are equivalent and the surface is
perfectly uniform.

53. • Freundlich isotherm equation is based on the
assumption that cations and anions are
adsorbed onto the same surface
simultaneously.
• This situation results in the formation of
attractive forces between adsorbed cations
and anions on the surface.
• Multi-layer adsorption can occur

54. Thermodynamic studies
• To study the effect of temperature
• Positive values of entalphy ∆H – endothermic
• Positive value of entropy ∆S confirms
possibility of favorable adsorption
• Negative value of free energy ∆G – removal to
be spontaneous