Oil palm empty fruit bunch (EFB) contributes to a large quantity of lignocellulosic waste. It is an abundantly available
waste biomass in Malaysia. This project was aimed to utilize the waste materials for a better benefit. EFB were used as
raw material to prepare a new solid catalyst for biodiesel production. Solid acid catalyst derived from EFB was used to
catalyze the esterification process in biodiesel production from waste cooking oil. Solid acid catalyst was prepared by
direct impregnation with transition metal sulfides, Fe2
(SO4
)3
. This new catalyst was used to catalyze the esterification of
high free fatty acid (FFA) value oil, e.g. waste cooking oils (WCOs) as pre-treatment step prior to biodiesel production.
The highest catalytic activity with 90.95% esterification rate was achieved. The catalyst can be easily separated for
reuse compared to homogenous catalyst which are used in biodiesel production. EFB has the potential to be converted
into useful feedstock and the derived catalyst can replace the traditional liquid acid catalyst in biodiesel production
especially for high acid value content feedstock.
Phenotypic selection of individuals is the first step in a selective breeding program for elite hybrid seed production. In
this study, a total of 295 Jatropha curcas individuals raised from cuttings representing 21 accessions, collected from eight
different countries were evaluated for growth performance. The evaluation was done at the Biodiesel Research Station
of Universiti Kebangsaan Malaysia, Kuala Pilah from December 2012 to December 2013. Individual plants from each
accession were observed on several agronomic and yield related traits and all the data were recorded periodically.
Performance of each accession was analyzed using Statistical Analysis System (SAS) 9.4. Four traits which were plant
height (PH), number of flowers per inflorescence (NFI), number of female flowers per inflorescence (NFFPI) and hundred
seed weight (HSW) showed significant differences among the accessions after one year of planting. Maximum values for
each trait were 115.5 cm for PH, 6 for number of branches per plant (BPP), 9 for number of inflorescences per plant
(NIPP), 25 for number of fruits per plant (NFPP), 5 for number of fruits per inflorescence (NFPI), 191 for NFI, 10 for
NFFPI, 81.0 g for HSW and 70 for number of seeds per plant (NSPP). Accession number 1 from Thailand showed the best
performance for most traits. A highly significant and positive correlation was found between NFPP and NSPP. Based on
superior trait values for NIPP, NFPP, NFPI, NFI, NFFPI and HSW, five plants from accession UKMJC 01, 04, 05, 13 and 14
have been selected for generating elite intraspecific hybrids.
MeSH terms: Selective Breeding; Body Weights and Measures; Female; Fruit; Malaysia; Seeds; Thailand; Jatropha; Flowers; Inflorescence; Biofuels
In this study carbide lime waste was used as raw material to produce precipitated calcium carbonate (PCC). Carbide
lime is an industrial waste from acetylene gas industry which uses limestone in its production. The use of PCC as fillers
in paper making can reduce the production cost and improve the paper properties such as opacity and brightness. PCC
can be produced from carbide lime waste by ionic sucrose solution method. The sucrose solution of Brix 10° was first
prepared by dissolving sugar (sucrose) in water followed by dissolution of carbide lime waste in the sucrose solution.
The sucrose solution which had turned milky was then filtered to obtain a clear solution known as pregnant solution.
The pregnant solution that contained calcium ions was subsequently used to produce PCC by introducing CO2
gas into
the pregnant solution. The process is known as carbonation. The PCC was then used as fillers in paper making. The
production of PCC by using calcium hydroxide as starting material was also carried out for comparison purposes. Based
on the results, PCC prepared from carbide lime had purity of 98.14% while the one prepared from calcium hydroxide had
98.66%. Meanwhile, analysis of the paper properties demonstrated that both products gave equally good results. This
proves that PCC prepared from industrial waste can be used for paper making.
Biological fermentation of Rhizopus oryzae was introduced to extract cellulose nanofibre from durian skin fibre (DSF).
The diameter of the extracted durian skin nanofibre (DSNF) was in the range of 49-81 nm. The changes of chemical
composition of DSNF were clearly seen after evaluated via TAPPI standard test methods. Verification via Fourier transform
infrared (FTIR) confirmed the deduction of hemicelluloses and lignin in DSNF in the range of 1200 to 1000 cm-1. X-ray
diffraction (XRD) demonstrated increment in the crystallinity from 58.3 to 72.2% after biological fermentation. DSNF was
then incorporated into polylactic acid (PLA) via extrusion and injection moulding processes. The effect of 1-5 wt. % DSNF
content on PLA biocomposites was investigated for its mechanical and thermal properties. The presence of only 1 wt. %
improved the tensile and impact strength by 14.1 MPa and 33.1 kJ/m2
, respectively. The thermal properties of PLA-1DSNF
biocomposite also recorded higher thermal stability, glass transition temperature (Tg
), crystallization temperature (Tc
)
and melting temperature (Tm). Additionally, from the DMA, it was determined that PLA-1DSNF possessed lower storage
modulus and loss modulus, as well as low energy dissipation.
This paper discussed on the preparation of natural CNF from kenaf bast fibre for the application as a support structure in
enzyme immobilization. The treatments involved for this preparation were delignification, bleaching and high-intensity
ultra-sonication process to obtain nanofibre with high cellulose content and less than 100 nm diameter. Chemical
composition analysis showed the influence of each process treatment on cellulose content of raw bast fibre, bleached
pulp fibre and CNF(63.67, 81.12 and 91.97%, respectively). By increasing the cellulose content and decreasing the size
of cellulose fibre, it resulted in a greater number of –OH functional group on its surface that plays as important role
in enzyme immobilization. FTIR spectroscopy confirms that the removal of lignin and hemicellulose from the fibre after
the treatments, as well as its interaction with coupling agents and CGTase enzyme. About 62.10% of enzyme loading
and 45.62% of its activity yield were obtained after immobilization. Enzymatic reaction of immobilized CGTase on CNF
indicates about more than 60% relative production yield of α-CD was achieved and its reusability was able to retain
about 67.0% from its initial activity after 8 cycles of reaction. Therefore, the CNF is a good potential as a support for
enzyme immobilization.
The main focus in this research was to understand the influence of Dy3+ and Eu3+ doping/co-doping and sintering atmosphere on the luminescence properties of SrB2 Si2 O8. Single phase Eu and Dy doped/co-doped SrB2 Si2 O8 ceramics were synthesized in different atmosphere through solid state reaction technique. An inexpensive method was occupied to provide reducing sintering atmosphere. Europium doped SrB2 Si2 O8 exhibit unusual reduction from trivalent to a divalent oxidation state even in an oxidizing atmosphere. We also discovered co-doping with Dy3+ ions produced further europium reduction in this phosphor. By manipulating the sintering condition and co-doping, a reddish-purple to blue tune-able phosphor under 390 nm excitations were produced and their Commission International del’Eclairage (CIE) color coordination were calculated and plotted in a CIE 1931 diagram. Photoluminescence spectra of the Eu2+/Eu3+ and Dy3+ co-doped SrB2 Si2 O8 phosphor showed energy transfer from Dy3+ to Eu3+ and Eu2+ which was observable in Dy3+ f-f excitation transitions and the Dy-O charge transfer bands. A weak 777 nm emission from 3p5 P to 3s5 S0 transition of O2- ions were observed in all the samples. The excitation and emission peaks of f - f transition from Dy3+ and Eu3+ as well as 4f - 5d transition of Eu2+ were also discussed. The long excitation band in ultraviolet (UV) region from these doped/co-doped SrB2 Si2 O8 ceramics produced phosphors with efficient UV excitation for solid state lighting.
Recent developments have found the viability of chitosan as a new alternative additive in the pulp and paper technology.
This study was carried out to investigate the effect of chitosan as a paper coating which were prepared by dissolution in
acetic acid solution. The mechanical properties of coated paper were improved significantly compared with non-coated
paper. The FT-IR spectra showed peak evolution at 1558 cm-1 for coated paper due to the existence of amine group. Since
FT-IR spectra for the coated paper was almost identical to the chitosan spectrum, it is assumed that there is an obvious
physical interaction rather than the chemical interaction. The SEM micrographs showed that some of the chitosan has
occupied the pores and some of them adhered only on the surface. This may be due to the chemical similarities between
cellulose and chitosan which enhanced the strength of fiber matrixes via hydrogen bonding. The antibacterial property
of coated paper showed that chitosan in dried form has no significant effect but effective when applied as wet solution.
Bioethanol is a very environmentally friendly liquid biofuel that is not only renewable, but also sustainable. It is currently
deemed as a highly suitable additive and substitute energy source to replace fossil based fuel. In this study, bioethanol
was produced from sago hampas by using commercial amylase, cellulase and Saccharomyces cerevisiae via sequential
saccharification and simultaneous fermentation (SSSF), a modified version of the simultaneous saccharification and
fermentation (SSF) process. SSSF was performed on sago hampas at 2.5 and 5.0% (w/v) feedstock load for five days. The
samples taken from the SSSF broths were analysed via high performance liquid chromatography (HPLC) for ethanol, glucose
and acetic acid production. From the results obtained, SSSF with 5.0% sago hampas loading exhibited the highest ethanol
production at 14.13 g/L (77.43% of theoretical ethanol yield), while SSSF using 2.5% sago hampas loading produced
ethanol at 6.45 g/L (69.24% of theoretical ethanol yield). This study has shown that ethanol not only can be produced
from sago hampas using different enzyme mixtures and S. cerevisiae via SSSF, but yields were also high, making this
process highly promising for the production of cheap and sustainable ethanol as fuel.
Levulinic acid (LA) is a versatile platform chemical with numerous potential uses. Conversion of oil palm fronds (OPF)
to LA over Fe/HY zeolite catalyst has been conducted in this study. The optimization process using Box-Behnken design
gave 19.6% of LA yield at 181.7°C reaction temperature, 7.7 h reaction time, 1.13 g Fe/HY zeolite loading and 0.25 g OPF
loading. The efficiency of OPF conversion at the optimum conditions was determined to be 61.1%. It was also demonstrated
that Fe/HY zeolite gave sufficient performance for five successive cycles of OPF conversion to LA. The results suggested
that Fe/HY zeolite is potential as catalyst for biomass conversion to LA.
A composite membrane was prepared by mixing epoxidized natural rubber (ENR) and polyvinyl chloride (PVC). An
inorganic filler, MgO, was introduced into the polymer matrix by certain percentages to form a mixed matrix membrane
(MMM). The resulting membranes were characterized using FTIR, TGA, SEM and gas permeability test. FTIR results showed
the incorporation of MgO inside the membrane matrix with the appearance of an absorption peak at 3700 cm-1 which
represents the formation of Mg(OH)2
. Thermogram from TGA analysis showed two degradation stages at 250-350°C
and 370-500°C, which correspond to the decomposition of PVC and ENR and the residue of fillers at 600°C. SEM images
of the membranes showed that pores were developed as fillers were introduced to the membrane. The size of the pores
also increased with the increase of filler percentage. As for gas permeation test, the permeability values of CO2
and N2
for ENR/PVC membrane were the lowest. The permeability values increased with the addition of MgO to the membrane.
The permeability of CO2
was also the highest for all membranes.
Epoxy shape memory foam (ESM) was produced by an advanced aqueous method. Mixture of epoxy, sodium bicarbonate,
hardener and ammonium chloride was premixed and emulsified in distilled water by using high speed stirring (at 1200
rpm). The content of sodium bicarbonate used was 5, 10, 15 and 20 phr. Besides that, ammonium chloride was used
(based on stoichiometrical content) to also function as acidifying agent in initiating the decomposition process of sodium
bicarbonate at lower foaming temperature. The foam morphology was observed using SEM. It was found that higher
sodium bicarbonate produced more porosity, more cell size, thinner cell wall and more cell interconnection. Epoxy shape
memory foam with 10 phr of sodium bicarbonate exhibited good shape memory property and better compression set.
Shape memory behaviour was measured by the recovered time of the transformed sample to its original shape.
An investigation on a batch production of palm kernel oil polyol (PKO-p) was conducted via esterification and condensation.
The process design was thoroughly studied as a preliminary step for future upscaling. The process variables included
necessity of vacuum pump, controlling of heating rate, recording the production time, nitrogen gas flow and agitator
speed. About 250 mL PKO-p was successfully synthesized within 3 h. Vacuum pressure was applied to haul out moisture
from the system. The control of heating rate and production time are vital to avoid sudden oxidation.
Graft copolymerization of acrylonitrile onto torch ginger cellulose was carried out in an aqueous medium with ceric ion
redox initiator. The optimum grafting parameters such as temperature, reaction time, ratio of monomer to cellulose addition
and ceric ammonium nitrate (CAN) concentration were determined and a maximum graft yield of 40% was recorded.
The graft copolymer was characterized and compared with untreated cellulose. A new absorption peak corresponding
to the nitrile group of acrylonitrile was recorded by FTIR at 2244 cm-1 on the grafted cellulose. The morphology studies
showed that the diameter and the surface roughness of grafted cellulose had increased as compared with the untreated
cellulose. On the contrary, the grafting had resulted in lowering the crystallinity of the cellulose from 63 to 53%. The
grafted cellulose produced a new derivative TG peak at 420°C and higher residual percentage than the untreated cellulose
A clear understanding on the fundamental mechanism in solid state self-healing resin system might significantly improve the optimization of healing performance. The focus of this study was to prove the diffusion (through thermal inter-diffusion) of a linear healing agent within the network matrix resin. The results had demonstrated that 45 to 21 percentage recoveries in fracture toughness (K1C) were observed within the third healing cycles of the healable resin. Based on the optical microscopy, scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIM) analyst; the diffusion of healing agent was also demonstrated by the change in the morphology and chemical images of the healing agent on the fracture surface specimen, before and after healing process.
In this study, Bacterial cellulose (BC) grafted with Acrylic acid (AA) was prepared using Co60 γ-rays source (30 KGy).
Although many samples were prepared, BC: AA with ratio of 1:1 labelled as A1 and 2:1 labelled as A2 gave the most
significant results. Hence these particular ratios have been selected and further investigated. AA was proven grafted onto
BC by using ATR-FTIR due to the absent of C-O stretching (1040 cm-1) in both hydrogels. The SEM image of both hydrogels
samples showed highly porosity networks structure have been produced. The physical properties of the hydrogels such
as equilibrium water content (%) and swelling ratio (%) in different pH buffer solution were measured. It was found
that the equilibrium water content (%) of A1 was 93.10% while A2 was 74.83%, respectively. The results indicated that
the equilibrium water content (%) increased by gaining the AA concentration. At pH10, the A2 swelling ratio (%) was
two folded with 3350% in comparison with the A1. For the removal of methylene blue (MB) from aqueous solution, the
results from the UV-VIS spectroscopy demonstrated that the A2 sample hydrogel was also an effective absorbent material
Synthetic materials that are capable of healing upon damage are being developed at a rapid pace because of their
many potential applications. Here, new healing chemically cross-linked hydrogel of poly(2-hydroxyethyl methacrylate)
(pHEMA) was prepared. The healing hydrogel was achieved by heating above its glass transition (Tg
). The intermolecular
diffusion of dangling chain and the chain slippage led to healing of the gel. The peaks in attenuated total reflectance
(ATR) confirmed that hydrogel was formed while rheological studies had determined the minimum for healing temperature
is 48.5o
C. The results showed that ratio stress of the healable hydrogel can reach until 92 and 91% of first and second
healing cycle, respectively. The morphology of the sample was carried out to evaluate the self-property of hydrogel.
MeSH terms: Diffusion; Glass; Heating; Methacrylates; Polyhydroxyethyl Methacrylate; Rheology; Temperature
Cellulose nanocrystals (CNC) from mengkuang leaves (Pandanus tectorius) were investigated as potential reinforcement
in poly(vinyl chloride) (PVC) matrix. The surface of CNC was modified with silane coupling agent to improve fillermatrix
adhesion. Solution casting method was used to prepare PVC nanocomposites with various amounts of modified
(SCNC) and unmodified (CNC) nanocrystals. Both SCNC and CNC were examined by Fourier transform infrared (FTIR)
spectroscopy and X-ray diffraction (XRD) which showed that surface chemical modification has occurred. An increase
in tensile strength was observed with the addition of SCNC compared to the CNC. However, the elongation at break of the
nanocomposites was found to decrease with the increase of both fillers loading. An increasing trend was observed in the
tensile modulus with the addition of CNC to the PVC matrix, but decreasing with the addition of SCNC. The morphology
of a fractured surface of nanocomposites showed silane modification reduced the number of voids in the structure of
PVC. The observation indicated the adhesion between the fiber and the matrix had improved upon surface modification
of the nanocrystals with silane.
In this research, a novel method was performed to obtain hydrogel with superior thermal stability by incorporation
of cellulose nanocrystals (CNC) into gelatin based hydrogel. Glutaraldehyde was used as cross-linker due to its high
chemical reactivity towards NH2
group on gelatin. Different ratio of gelatin/CNC hydrogel was produced in order to study
the effects of CNC towards the swelling behaviour and thermal stability of gelatin based hydrogel. The obtained hydrogel
was subjected to Fourier transform infrared (FTIR) to verify that gelatin had been cross-linked, swelling test with different
pH for swelling behaviour and thermogravimetric analysis (TGA) for thermal stability. The presence of C=N stretching
group in the FTIR spectrum for gelatin/CNC hydrogel indicated that the cross-linking reaction between gelatin monomer
had been successfully carried out. The hydrogel showed impressive pH sensitivity and maximum swelling was obtained
at pH3. The TGA results clearly showed that the incorporation of CNC into gelatin was able to produce hydrogel with
higher thermal stability compare to neat gelatin.
Composite based on spear grass with low density polyethylene (LDPE)/soya spent powder (SSP) were prepared by using
twin screw extruder at 150o
C. The spear grass (SG) loading was ranged from 0 to 15%. A compatibilizer, epoxidized
natural rubber (ENR 50) with 50 mol % epoxidation was added. The effect of filler content and compatibilizer on the
properties of LDPE/ SSP composite was studied. The results indicated that the increase of SG loading leads to the reduction
of tensile strength and elongation at break (Eb
), whereas the Young’s modulus has increased. Differential scanning
calorimeter (DSC), indicated that the melting temperature and crystallinity of the composites decreased with the increase
of SG loading. After the addition of ENR 50, the melting temperature increases from 98.33 to 98.63o
C for 95% LDPE, 5%
SSP and 5% SG, whereas the crystallinity of the same ratio decreased from 31.92 to 28.13%.
The purpose of this study was to produce a novel pH sensitive hydrogel with superior thermal stability, composed of
poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali
and bleaching treatments followed by acid hydrolysis. PAA was then subjected to chemical cross-linking using the crosslinking
agent (N,N-methylenebisacrylamide) in CNC suspension. The mixture was casted onto petri dish to obtain disc
shape hydrogel. PAA/cellulose hydrogel with the same composition ratio were also prepared as control. The effect of
reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH
was studied. The obtained hydrogel was further subjected to different tests such as thermogravimetric analysis (TGA) to
study the thermal behavior, Fourier transform infrared for functional group identification and swelling test for swelling
behavior at different pH. The cross-linking of PAA was verified with FTIR with the absence of C=C double bond. In TGA
test, PAA/CNC hydrogel showed significantly higher thermal stability compared with pure PAA hydrogel. The hydrogel
obtained showed excellent pH sensitivity and experienced maximum swelling at pH7. The PAA/CNC hydrogel can be
developed further as drug carrier
MeSH terms: Acrylamides; Acrylic Resins; Alkalies; Cellulose; Drug Carriers; Fourier Analysis; Hydrolysis; Social Identification; Spectroscopy, Fourier Transform Infrared; Hibiscus; Nanoparticles