Alina Rahayu Mohamed

Optimization of the pyrolysis process of empty fruit bunch (EFB) in a fixed-bed reactor through a central composite design (CCD)

The production of crude palm oil from the processing of palm fresh fruit bunches in the palm oil mills in Malaysia hs resulted in a huge quantity of empty fruit bunch (EFB) accumulated. The EFB was used as a feedstock in the pyrolysis process using a fixed-bed reactor in the present study. The optimization of process parameters such as pyrolysis temperature (factor A), biomass particle size (factor B) and holding time (factor C) were investigated through Central Composite Design (CCD) using Stat-Ease Design Expert software version 7 with bio-oil yield considered as the response. Twenty experimental runs were conducted. The results were completely analyzed by Analysis of Variance (ANOVA). The model was statistically significant. All factors studied were significant with p-values < 0.05. The pyrolysis temperature (factor A) was considered as the most significant parameter because its F-value of 116.29 was the highest. The value of R2 was 0.9564 which indicated that the selected factors and its levels showed...

Preparation and Structural Characterization of CaCu3Ti4O12 Doped with Nickel, Ferrite, Manganese and Cobalt

Transition metal oxide-doped CCTO (CaCu3Ti4O12) ceramics were prepared by a conventional solgel synthesis method and the effects of pure CCTO and CCTO doped with Mn, Fe, Co, Ni to the crystal structure, microstructures and dielectrical properties of samples were investigated. The phase composition and microstructure were studied by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD analysis reveals that all samples exhibited multiphases with the pseudo-perovskite cubic CCTO phase with space group Im-3 as the main phase in undoped and doped CCTO samples. Peaks of monoclinic CuO and peroveskite CaTiO3 could also be seen in all samples which indicate that solid solution of CuO in CaTiO3 lattice was incomplete.SEM results show that doping effectively enhanced densification. SEM micrographs also suggested that the morphologies of doped CCTO ceramics had showed a matrix consisting of large grains wherein the small grains were embedded between the larger grains. Dielectric properties of pure and doped CCTO were investigated in a broad frequency range of the dielectric constant reached a value as high as εr = 29.4 at room temperature for CCTO doped with Ni at frequency (1000 Hz). Besides the sintering conditions, the microstructure and the dielectric properties of the CCTO are strongly influenced by type of doping elements.

The Effects of Process Parameters on the Pyrolysis of Empty Fruit Bunch (EFB) Using a Fixed-Bed Reactor

Malaysia is well-known as one of the main producer and exporter of palm oil. With the high production of crude palm oil (CPO), huge amount of empty fruit bunch was generated as by-products. The abundant amount of EFB produced required careful waste management procedures. Pyrolysis is thermochemical decomposition of biomass in inert environment towards its conversion into bio-oil, bio-char and gas. In this study, the pyrolysis of empty fruit bunch (EFB) was conducted using a fixed bed reactor. The pertinent process parameters such as pyrolysis temperature, particle sizes and heating rates were investigated via the determination of the percentage product yields such as bio-oil, bio-char and gas. The first series of experiment was conducted to determine the effect of pyrolysis temperatures. The final pyrolysis temperature was varied at 300, 400, 500, 600 and 700 °C at constant heating rates and the nitrogen flowrates of 30 °C/min and 100 cm3/min respectively. It was determined that at pyrolysis temperature of 500 °C maximum bio-oil yield of 35.00 % was obtained with bio-char and gas yield of 26.98 and 38.02% respectively. In the second series of experiment, the effect of particle sizen was studied. The EFB particle was varied at <125, 125-250, 250-500, 500-710 and 710-1000 μm. The pyrolysis temperature was fixed at 500 °C with nitrogen flowrate of 100 cm3/min and heating rate of 30 °C/min. It was determined that using EFB particle size of 250-500 μm, the maximum bio-oil of 38.52% was achieved with bio-char and gas yields of 25.06 % and 36.42% respectively. In the third series of experiment to determine the effect of heating rates, the heating rates was varied at 10, 20, 30, 40, 50 and 60 °C/min towards the final pyrolysis temperature of 500 °C with constant nitrogen flowrates of 100 cm3/min. The results obtained showed that the highest amount of bio-oil of 40.81% was obtained when the heating rate of 20 °C/min was used. The bio-char and gas yield obtained were 24.69% and 34.50% respectively.