Suzana Yusup

Catalytic cracking of bio-oil to organic liquid product (OLP).

The main objective of this paper is to find the optimum operating condition to upgrade the EFB-derived pyrolysis oil (bio-oil) to liquid fuel, mainly gasoline using Taguchi Method. From the analysis that has been done, it is found that the optimum operating condition for heterogeneous catalytic cracking process is at 400 degrees C, 15min of reaction time using 30g of catalyst weight where operating at this condition produced the highest yield of gasoline fraction which is 91.67 wt.%. This observation proves that EFB-derived pyrolysis oil could be upgraded via heterogeneous catalytic cracking to produce gasoline.

Reactive extraction of Jatropha curcas L. seed for production of biodiesel: process optimization study.

Biodiesel from Jatropha curcas L. seed is conventionally produced via a two-step method: extraction of oil and subsequent esterification/transesterification to fatty acid methyl esters (FAME), commonly known as biodiesel. Contrarily, in this study, a single step in situ extraction, esterification and transesterification (collectively known as reactive extraction) of J. curcas L. seed to biodiesel, was investigated and optimized. Design of experiments (DOE) was used to study the effect of various process parameters on the yield of FAME. The process parameters studied include reaction temperature (30-60 degrees C), methanol to seed ratio (5-20 mL/g), catalyst loading (5-30 wt %), and reaction time (1-24 h). The optimum reaction condition was then obtained by using response surface methodology (RSM) coupled with central composite design (CCD). Results showed that an optimum biodiesel yield of 98.1% can be obtained under the following reaction conditions: reaction temperature of 60 degrees C, methanol to seed ratio of 10.5 mL/g, 21.8 wt % of H(2)SO(4), and reaction period of 10 h.

Production of a bioflocculant from Aspergillus niger using palm oil mill effluent as carbon source

This study evaluated the potential of bioflocculant production from Aspergillus niger using palm oil mill effluent (POME) as carbon source. The bioflocculant named PM-5 produced by A. niger showed a good flocculating capability and flocculating rate of 76.8% to kaolin suspension could be achieved at 60 h of culture time. Glutamic acid was the most favorable nitrogen source for A. niger in bioflocculant production at pH 6 and temperature 35 °C. The chemical composition of purified PM-5 was mainly carbohydrate and protein with 66.8% and 31.4%, respectively. Results showed the novel bioflocculant (PM-5) had high potential to treat river water from colloids and 63% of turbidity removal with the present of Ca(2+) ion.

Optimisation on pretreatment of rubber seed (Hevea brasiliensis) oil via esterification reaction in a hydrodynamic cavitation reactor.

Pretreatment of the high free fatty acid rubber seed oil (RSO) via esterification reaction has been investigated by using a pilot scale hydrodynamic cavitation (HC) reactor. Four newly designed orifice plate geometries are studied. Cavities are induced by assisted double diaphragm pump in the range of 1-3.5 bar inlet pressure. An optimised plate with 21 holes of 1mm diameter and inlet pressure of 3 bar resulted in RSO acid value reduction from 72.36 to 2.64 mg KOH/g within 30 min of reaction time. Reaction parameters have been optimised by using response surface methodology and found as methanol to oil ratio of 6:1, catalyst concentration of 8 wt%, reaction time of 30 min and reaction temperature of 55°C. The reaction time and esterified efficiency of HC was three fold shorter and four fold higher than mechanical stirring. This makes the HC process more environmental friendly.

Microwave-assisted methyl esters synthesis of Kapok (Ceiba pentandra) seed oil: parametric and optimization study

Article history: The depleting fossil fuel reserves and increasing environmental concerns have continued to stimulate research into biodiesel as a green fuel alternative produced from renewable resources. In this study, Kapok (Ceiba pentandra) oil methyl ester was produced by using microwave-assisted technique. The optimum operating conditions for the microwave-assisted transesterification of Kapok seed oil including temperature, catalyst loading, methanol to oil molar ratio, and irradiation time were investigated by using Response Surface Methodology (RSM) based on Central Composite Design (CCD). A maximum conversion of 98.9 % was obtained under optimum conditions of 57.09 °C reaction temperature, 2.15 wt% catalyst (KOH) loading, oil to methanol molar ratio of 1:9.85, and reaction time of 3.29 min. Fourier Transform Infra-Red (FT-IR) spectroscopy was performed to verify the conversion of the fatty acid into methyl esters. The properties of Kapok oil methyl ester produced under the optimum conditions were characterized and found in agreement with the international ASTM D 6751 and EN 14214 standards.

Modeling of reaction kinetics for transesterification of palm-based methyl esters with trimethylolpropane

A mathematical model describing chemical kinetics of transesterification of palm-based methyl esters with trimethylolpropane has been developed. The model was developed by utilizing nonlinear regression method, which is an efficient and powerful way to determine rate constants for both forward and reverse reactions. A comparison with previous study which excludes the reverse reactions was made. The model was based on the reverse mechanism of transesterification reactions and describes concentration changes of trimethylolpropane, monoesters and diesters production. The developed model was validated against data from the literature. The reaction rate constants were determined using MATLAB version 7.2 and the ratios of rate constants obtained were well in agreement with those reported in the literature. A good correlation between model simulations and experimental data was observed. It was proven that both methods were able to predict the rate constants with plausible accuracy.

Ionic liquids assisted processing of renewable resources for the fabrication of biodegradable composite materials

In recent years, the utilization of renewable resources, particularly lignocellulosic biomass based raw materials, to replace synthetic materials/polymers for the manufacture of green materials has gained increased worldwide interest due to growing global environmental awareness, concepts of sustainability and the absence of conflict between food and chemical/materials production. However, structural heterogeneity and the presence of networks of inter- and intra-molecular interactions in biopolymer matrices remain unsolved challenges to clean pretreatment for biocomposite processing. A number of techniques including physical, physico-chemical and chemical methods have been investigated for the pretreatment of renewable resources. Most of these methods require high temperatures and pressures, as well as highly concentrated chemicals for the pretreatment process. Fortunately, ionic liquids (ILs) – potentially attractive “green” recyclable alternatives to environmentally harmful organic solvents – have been increasingly exploited as solvents and/or (co)solvents and/or reagents for biopolymer processing. Compared to conventional approaches, ILs in processing biodegradable composites exhibit many advantages such as being noncorrosive and nonvolatile, having excellent dissolution power under relatively mild conditions and high thermal stability. Presently, a wide range of different approaches have been explored to further improve the performance of ILs processing of biobased polymers for composites manufacturing. The main goal of this review is to present recent technological developments in which the advantages of ILs as processing solvents for biopolymers for the production of a plethora of green composites have been gradually realized. It is hoped that the present article will inspire new ideas and new approaches in ILs-assisted processing of renewable resources for green composite production.

Characterization of natural low transition temperature mixtures (LTTMs): Green solvents for biomass delignification

The aim of this work was to characterize the natural low transition temperature mixtures (LTTMs) as promising green solvents for biomass pretreatment with the critical characteristics of cheap, biodegradable and renewable, which overcome the limitations of ionic liquids (ILs). The LTTMs were derived from inexpensive commercially available hydrogen bond acceptor (HBA) and l-malic acid as the hydrogen bond donor (HBD) in distinct molar ratios of starting materials and water. The peaks involved in the H-bonding shifted and became broader for the OH groups. The thermal properties of the LTTMs were not affected by water while the biopolymers solubility capacity of LTTMs was improved with the increased molar ratio of water and treatment temperature. The pretreatment of oil palm biomass was consistence with the screening on solubility of biopolymers. This work provides a cost-effective alternative to utilize microwave hydrothermal extracted green solvents such as malic acid from natural fruits and plants.

Influence of Fuel Moisture Content and Reactor Temperature on the Calorific Value of Syngas Resulted from Gasification of Oil Palm Fronds

Biomass wastes produced from oil palm mills and plantations include empty fruit bunches (EFBs), shells, fibers, trunks, and oil palm fronds (OPF). EFBs and shells are partially utilized as boiler fuel while the rest of the biomass materials like OPF have not been utilized for energy generation. No previous study has been reported on gasification of oil palm fronds (OPF) biomass for the production of fuel gas. In this paper, the effect of moisture content of fuel and reactor temperature on downdraft gasification of OPF was experimentally investigated using a lab scale gasifier of capacity 50 kW. In addition, results obtained from equilibrium model of gasification that was developed for facilitating the prediction of syngas composition are compared with experimental data. Comparison of simulation results for predicting calorific value of syngas with the experimental results showed a satisfactory agreement with a mean error of 0.1 MJ/Nm3. For a biomass moisture content of 29%, the resulting calorific value for the syngas was found to be only 2.63 MJ/Nm3, as compared to nearly double (4.95 MJ/Nm3) for biomass moisture content of 22%. A calorific value as high as 5.57 MJ/Nm3 was recorded for higher oxidation zone temperature values.

Optimization of hydrogen and syngas production from PKS gasification by using coal bottom ash

Catalytic steam gasification of palm kernel shell is investigated to optimize operating parameters for hydrogen and syngas production using TGA-MS setup. RSM is used for experimental design and evaluating the effect of temperature, particle size, CaO/biomass ratio, and coal bottom ash wt% on hydrogen and syngas. Hydrogen production appears highly sensitive to all factors, especially temperature and coal bottom ash wt%. In case of syngas, the order of parametric influence is: CaO/biomass>coal bottom ash wt%>temperature>particle size. The significant catalytic effect of coal bottom ash is due to the presence of Fe2O3, MgO, Al2O3, and CaO. A temperature of 692°C, coal bottom ash wt% of 0.07, CaO/biomass of 1.42, and particle size of 0.75mm are the optimum conditions for augmented yield of hydrogen and syngas. The production of hydrogen and syngas is 1.5% higher in the pilot scale gasifier as compared to TGA-MS setup.