Palm oil is one of the most important agroindustries in Malaysia. Huge quantities of palm oil mill effluent (POME) pose a great threat to aqueous environment due to its very high COD. To make full use of discharged wastes, the integrated "zero discharge" pilot-scale industrial plant comprising "pretreatment-anaerobic and aerobic process-membrane separation" was continuously operated for 1 year. After pretreatment in the oil separator tank, 55.6% of waste oil in raw POME could be recovered and sold and anaerobically digested through 2 AnaEG reactors followed by a dissolved air flotation (DAF); average COD reduced to about 3587 mg/L, and biogas production was 27.65 times POME injection which was used to generate electricity. The aerobic effluent was settled for 3 h or/and treated in MBR which could remove BOD3 (30°C) to less than 20 mg/L as required by Department of Environment of Malaysia. After filtration by UF and RO membrane, all organic compounds and most of the salts were removed; RO permeate could be reused as the boiler feed water. RO concentrate combined with anaerobic surplus sludge could be used as biofertilizer.
CO2 gasification of oil palm shell (OPS) char to produce CO through the Boudouard reaction (C + CO2 ↔ 2CO) was investigated under microwave irradiation. A microwave heating system was developed to carry out the CO2 gasification in a packed bed of OPS char. The influence of char particle size, temperature and gas flow rate on CO2 conversion and CO evolution was considered. It was attempted to improve the reactivity of OPS char in gasification reaction through incorporation of Fe catalyst into the char skeleton. Very promising results were achieved in our experiments, where a CO2 conversion of 99% could be maintained during 60 min microwave-induced gasification of iron-catalyzed char. When similar gasification experiments were performed in conventional electric furnace, the superior performance of microwave over thermal driven reaction was elucidated. The activation energies of 36.0, 74.2 and 247.2 kJ/mol were obtained for catalytic and non-catalytic microwave and thermal heating, respectively.
Many kinetics studies on methanolysis assumed the reactions to be irreversible. The aim of the present work was to study the dynamic modeling of reversible methanolysis of Jatropha curcas oil (JCO) to biodiesel. The experimental data were collected under the optimal reaction conditions: molar ratio of methanol to JCO at 6 : 1, reaction temperature of 60°C, 60 min of reaction time, and 1% w/w of catalyst concentration. The dynamic modeling involved the derivation of differential equations for rates of three stepwise reactions. The simulation study was then performed on the resulting equations using MATLAB. The newly developed reversible models were fitted with various rate constants and compared with the experimental data for fitting purposes. In addition, analysis of variance was done statistically to evaluate the adequacy and quality of model parameters. The kinetics study revealed that the reverse reactions were significantly slower than forward reactions. The activation energies ranged from 6.5 to 44.4 KJ mol⁻¹.
The stearin fraction of palm-based diacylglycerol (PDAGS) was produced from dry fractionation of palm-based diacylglycerol (PDAG). Bakery shortening blends were produced by mixing PDAGS with either palm mid fraction, PMF (PDAGS/PMF), palm olein, POL(PDAGS/POL) or sunflower oil, SFO (PDAGS/SFO) at PDAGS molar fraction of XPDAGS=0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%. The physicochemical results obtained indicated that C16:0 and C18:1 were the dominant fatty acids for PDAGS/PMF and PDAGS/POL, while C18:1 and C18:2 were dominant in the PDAGS/SFO mixtures. SMP and SFC of the PDAGS were reduced with the addition of PMF, POL and SFO. Binary mixtures of PDAGS/PMF had better structural compatibility and full miscibility with each other. PDAGS/PMF and PDAGS/SFO crystallised in β'+β polymorphs in the presence of 0.4-0.5% PDAGS while PDAGS/POL resulted in β polymorphs crystal. The results gave indication that PDAGS: PMF at 50%:50% and 60%:40% (w/w) were the most suitable fat blend to be used as bakery shortening.
The aim of this study was to investigate the effect of atmospheric frying followed by drainage under vacuum on the stability of oil, compared to similar frying with drainage at atmospheric pressure. Changes in the oil were assessed by the free fatty acid (FFA) content, p-anisidine value (AnV), colour, viscosity, fatty acid profile and concentration of tocols. The rate of FFA formation in the case of vacuum drainage was found to be about half that of atmospheric drainage. Oil deterioration by oxidation and polymerisation was also reduced by the use of vacuum drainage. The AnV of the oil after vacuum drainage was lower by about 12%, the total colour difference was improved by 14% and viscosity was slightly reduced after 5 days of frying, compared to the values for oil that had been drained at atmospheric pressure. There was a reduction in the loss of polyunsaturated fatty acids in the case of vacuum drainage after 5 days of frying but differences in retention of tocols were only evident in the first two days of frying.
High PHA production and storage using palm oil mill effluent (POME) was investigated using a laboratory batch Bio-PORec® system under aerobic-feeding conditions. Results showed that maximum PHA was obtained at a specific rate (q(p)) of 0.343 C-mol/C-molh when air was supplied at 20 ml/min. The PHA yield was found to be 0.80 C-mol/C-mol acetic acid (HAc) at microaerophilic condition and the mass balance calculation showed that PHA production increased up to 15.68±2.15 C-mmol/cycle. The experiments showed that short feeding rate, limited requirements for electron acceptors (e.g. O(2), NO(3)) and nutrients (N and P) showed lower tendency of glycogen accumulation and contributed more to PHA productivity.
Supercritical fluid extraction (SFE), which has received much interest in its use and further development for industrial applications, is a method that offers some advantages over conventional methods, especially for the palm oil industry. SC-CO₂ refers to supercritical fluid extraction (SFE) that uses carbon dioxide (CO₂) as a solvent which is a nontoxic, inexpensive, nonflammable, and nonpolluting supercritical fluid solvent for the extraction of natural products. Almost 100% oil can be extracted and it is regarded as safe, with organic solvent-free extracts having superior organoleptic profiles. The palm oil industry is one of the major industries in Malaysia that provides a major contribution to the national income. Malaysia is the second largest palm oil and palm kernel oil producer in the World. This paper reviews advances in applications of supercritical carbon dioxide (SC-CO₂) extraction of oils from natural sources, in particular palm oil, minor constituents in palm oil, producing fractionated, refined, bleached, and deodorized palm oil, palm kernel oil and purified fatty acid fractions commendable for downstream uses as in toiletries and confectionaries.
Hydrodistillation of the fresh leaves of Alpinia mutica afforded 0.005% colourless essential oil. GC and GC-MS analysis revealed the presence of 33 components accounting for 92.9% of the total oil, dominated by 20 sesquiterpenes (76.7%) and 10 monoterpenes (8.3%). The major constituent was found to be β-sesquiphellandrene which was 29.2% of the total oil. Soxhlet extraction, followed by repeated column chromatography of the dried leaves yielded two phenolic compounds, identified as 5,6-dehydrokawain and aniba dimer A, together with one amide assigned as auranamide. The structures of these compounds were determined by using spectroscopic analysis. Antibacterial screening of the essential oil, the crude and isolated compounds showed weak to moderate inhibitory activity.
This paper reports a computational approach for analysis of FTIR spectra where peaks are detected, assigned and matched across samples to produce a peak table with rows corresponding to samples and columns to variables. The algorithm is applied on a dataset of 103 spectra of a broad range of edible oils for exploratory analysis and variable selection using Self Organising Maps (SOMs) and t-statistics, respectively. Analysis on the resultant peak table allows the underlying patterns and the discriminatory variables to be revealed. The algorithm is user-friendly; it involves a minimal number of tunable parameters and would be useful for analysis of a large and complicated FTIR dataset.
In this study, optical and thermal properties of normal grade and winter grade palm oil biodiesel were investigated. Surface Plasmon Resonance and Photopyroelectric technique were used to evaluate the samples. The dispersion curve and thermal diffusivity were obtained. Consequently, the variation of refractive index, as a function of wavelength in normal grade biodiesel is faster than winter grade palm oil biodiesel, and the thermal diffusivity of winter grade biodiesel is higher than the thermal diffusivity of normal grade biodiesel. This is attributed to the higher palmitic acid C(16:0) content in normal grade than in winter grade palm oil biodiesel.
The essential oils obtained by hydrodistillation of the rhizomes of Alpinia aquatica Rosc. syn. Alpinia melanocarpa and Alpinia malaccensis Roscoe were analysed by capillary gas chromatography and gas chromatography-mass spectrometry. Eighteen compounds, representing 98.4% of the essential oil were identified in A. aquatica rhizome oil, with β-sesquiphellandrene in 36.5% being the major constituent, while 20 compounds representing 99.7% of the rhizome oil of A. malaccensis were identified, among which methyl (E)-cinnamate (78.2%) was the major constituent.
Red fruit (Pandanus conoideus Lam) is endemic plant of Papua, Indonesia and Papua New Guinea. The price of its oil (red fruit oil, RFO) is 10-15 times higher than that of common vegetable oils; consequently, RFO is subjected to adulteration with lower price oils. Among common vegetable oils, canola oil (CaO) and rice bran oil (RBO) have similar fatty acid profiles to RFO as indicated by the score plot of principal component analysis; therefore, CaO and RBO are potential adulterants in RFO.
Decomposition of oil palm fruit press fiber (FPF) to various liquid products in subcritical water was investigated using a high-pressure autoclave reactor with and without the presence of catalyst. When the reaction was carried in the absence of catalyst, the conversion of solid to liquid products increased from 54.9% at 483 K to 75.8% at 603 K. Simultaneously, the liquid yield increased from 28.8% to 39.1%. The liquid products were sub-categorized to bio-oil (benzene soluble, diethylether soluble, acetone soluble) and water soluble. When 10% ZnCl(2) was added, the conversion increased slightly but gaseous products increased significantly. However, when 10% Na(2)CO(3) and 10% NaOH were added independently, the solid conversion increased to almost 90%. In the presence of catalyst, the liquid products were mainly bio-oil compounds. Although solid conversion increased at higher reaction temperature, but the liquid yield did not increase at higher temperature.
Fatty amides have been successfully synthesized from palm olein and urea by a one-step lipase catalyzed reaction. The use of immobilized lipase as the catalyst for the preparation reaction provides an easy isolation of the enzyme from the products and other components in the reaction mixture. The fatty amides were characterized using Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance ((1)H NMR) technique and elemental analysis. The highest conversion percentage (96%) was obtained when the process was carried out for 36 hours using urea to palm oil ratio of 5.2: 1.0 at 40 degrees C. The method employed offers several advantages such as renewable and abundant of the raw material, simple reaction procedure, environmentally friendly process and high yield of the product.
The combination of plant oils and 3-hydroxyvalerate (3HV) precursors were evaluated for the biosynthesis of polyhydroxyalkanoate (PHA) copolymers containing 3HV monomers by Cupriavidus necator H16. Among various mixtures of plant oils and 3HV-precursors, the mixture of palm kernel oil and sodium propionate was suitable for the biosynthesis of high concentration of PHA (6.8gL(-1)) containing 7mol% of 3HV. The 3HV monomer composition can be regulated in the range of 0-23mol% by changing culture parameters such as the initial pH, and the nitrogen source and its concentration. PHA copolymers with high weight-average molecular weights (Mw) ranging from 1,400,000 to 3,100,000Da were successfully produced from mixtures of plant oils and 3HV-precursors. The mixture of plant oils and sodium propionate resulted in PHA copolymers with higher M(w) compared to the mixture of plant oils and sodium valerate. DSC analysis on the PHA containing 3HV monomers showed the presence of two distinct melting temperature (Tm), which indicated that the PHA synthesized might be a blend of P(3HB) and P(3HB-co-3HV). Sodium propionate appears to be the better precursor of 3HV than sodium valerate.
In Malaysia, there has been interest in the utilization of palm oil and oil palm biomass for the production of environmental friendly biofuels. A biorefinery based on palm oil and oil palm biomass for the production of biofuels has been proposed. The catalytic technology plays major role in the different processing stages in a biorefinery for the production of liquid as well as gaseous biofuels. There are number of challenges to find suitable catalytic technology to be used in a typical biorefinery. These challenges include (1) economic barriers, (2) catalysts that facilitate highly selective conversion of substrate to desired products and (3) the issues related to design, operation and control of catalytic reactor. Therefore, the catalytic technology is one of the critical factors that control the successful operation of biorefinery. There are number of catalytic processes in a biorefinery which convert the renewable feedstocks into the desired biofuels. These include biodiesel production from palm oil, catalytic cracking of palm oil for the production of biofuels, the production of hydrogen as well as syngas from biomass gasification, Fischer-Tropsch synthesis (FTS) for the conversion of syngas into liquid fuels and upgrading of liquid/gas fuels obtained from liquefaction/pyrolysis of biomass. The selection of catalysts for these processes is essential in determining the product distribution (olefins, paraffins and oxygenated products). The integration of catalytic technology with compatible separation processes is a key challenge for biorefinery operation from the economic point of view. This paper focuses on different types of catalysts and their role in the catalytic processes for the production of biofuels in a typical palm oil and oil palm biomass-based biorefinery.
This study proposed an oil palm by-product as a low-cost adsorbent for the removal of hexavalent chromium [Cr (VI)] from aqueous solution. Adsorption of Cr (VI) by sulphuric acid and heat-treated oil palm fibre was conducted using batch tests. The influence of pH, contact time, initial chromium concentration and adsorbent dosage on the removal of Cr (VI) from the solutions was investigated. The optimum initial pH for maximum uptake of Cr (VI) from aqueous solution was found to be 1.5. The removal efficiency was found to correlate with the initial Cr (VI) concentration, adsorbent dosage as well as the contact time between Cr (VI) and the adsorbent. The adsorption kinetics tested with pseudo first order and pseudo second order models yielded high R(2) values from 0.9254 to 0.9870 and from 0.9936 to 0.9998, respectively. The analysis of variance (ANOVA) showed significant difference between the R(2) values of the two models at 99% confidence level. The Freundlich isotherm (R(2)=0.8778) described Cr (VI) adsorption slightly better than the Langmuir isotherm (R(2)=0.8715). Difficulty in desorption of Cr (VI) suggests the suitability of treated oil palm fibre as a single-use adsorbent for Cr (VI) removal from aqueous solution.
Rainfall-runoff processes in a small oil palm catchment (8.2 ha) in Johor, Malaysia were examined. Storm hydrographs show rapid responses to rainfall with a short time to peak. The estimated initial hydrologic loss for the oil palm catchment is 5 mm. Despite the low initial loss, the catchment exhibits a high proportion of baseflow, approximately 54% of the total runoff. On an event basis, the stormflow response factor and runoff coefficient ranges from 0.003 to 0.21, and 0.02 to 0.44, respectively. Peakflow and stormflow volume were moderately correlated with rainfall. The hydrographs were satisfactorily modelled using the Hydrologic Engineering Centre-Hydrologic Modelling System (HEC-HMS). The efficiency indexes of the calibration and validation exercises are 0.81 and 0.82, respectively. Based on these preliminary findings, it could be suggested that an oil palm plantation would be able to serve reasonably well in regulating basic hydrological functions.
Studies were carried out on heat treatment of bamboo species Gigantochloa scortechinii Gamble using palm oil. The samples were laminated and glued. The adhesion results showed that the delamination of glue line increased as the temperature and duration of oil heat treatment increased. Maximum load and shear strength of the glue line reduced as the heat treatment become more severe. It was found that the palm oil used as the heating medium penetrated in some parts of the cell wall as well as in the cell lumen of the bamboo.
Palm oil is the richest source of natural carotenes, comprising 500-700 ppm in crude palm oil (CPO). Its concentration is found to be much higher in oil extracted from palm-pressed fiber, a by-product from the milling of oil palm fruits. There are 11 types of carotenes in palm oil, excluding the cis/trans isomers of some of the carotenes. Qualitative separation of these individual carotenes is particularly useful for the identification and confirmation of different types of oil as the carotenes profile is unique to each type of vegetable oil. Previous studies on HPLC separation of the individual palm carotenes reported a total analyses time of up to 100 min using C30 stationary phase. In this study, the separation was completed in <5 min. The qualitative separation was successfully carried out using a commonly used stationary phase, C18.