Roshafima Rasit Ali

Rice Husk/High Density Polyethylene Bio-Composite: Effect of Rice Husk Filler Size and Composition on Injection Molding Processability with Respect to Impact Property

The compounding of rice husk and high density polyethylene (HDPE) was undertaken on a Sino PSM 30 co-rotating twin screw extruder. Four sizes of rice husk were studied at various compositions. The size ranged from 500 μm and below (coded A, B, C and D) while the content of rice husk in the composite varies from 30, 40 and 50 percent of weight. A fixed amount of Ultra-Plast TP10 as a compatibilizer and Ultra-Plast TP 01 as lubricant, were added into the bio-composite compound. The injection molding process ability of the bio-composite was studied through flow behavior on melt flow indexer and analyzed on JSW N100 B11 Injection Molding. Size A which has the largest particle is the most appropriate size as the bio-composite filler based on thermal stability test. The melt flow rate of rice husk/HDPE (RHPE) decreases with the increased in rice husk compositions and apparent viscosity also increases with composition for all filler size. Melt flow rate above 4g/10 min was found to be the lower limit for injection molding process. The smaller the filler size, the lower is the impact strength and the increased in the filler composition lowers the impact strength. A bio-composite at 30 weight percent rice husk size A (RH30PEA) was found to have optimum rheological properties with respect to impact strength.

Starch Based Biofilms for Green Packaging

The aim of this study is to develop degradable starch-based packaging film with enhanced mechanical properties. A series of low-density polyethylene (LDPE)/tapioca starch compounds with various tapioca starch contents were prepared by twin-screw extrusion with the addition of maleic anhydride-grafted polyethylene as compatibilizer. Palm cooking oil was used as processing aid to ease the blown film process; thus, degradable film can be processed via conventional blown film machine. Studies on their mechanical properties and biodegradation were carried out by tensile test and exposure to fungi environment, respectively. The presence of high starch contents had an adverse effect on the tensile properties of LDPE/tapioca starch blends. However, the addition of compatibilizer to the blends improved the interfacial adhesion between the two materials and hence improved the tensile properties of the films. High content of starch was also found to increase the rate of biodegradability of LDPE/tapioca starch films. It can be proved by exposure of the film to fungi environment. A growth of microbes colony can be seen on the surface of LDPE/tapioca starch film indicates that the granular starch present on the surface of the polymer film is attacked by microorganisms, until most of it is assimilated as a carbon source.

Tapioca starch biocomposite for disposable packaging ware

Tapioca Starch Biocomposite for Disposable Packaging Ware Roshafima R. Ali*, Wan A. W. A. Rahman, Rafiziana M. Kasmani, Norazana Ibrahim, Siti N. H. Mustapha, Hasrinah Hasbullah Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia. Gas Engineering Department, FPREE, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia. roshafima@cheme.utm.my

Effect of evaporation time on cellulose acetate membrane for gas separation

Throughout this decades, membrane technology has been the desirable option among the others gas separation technologies. However, few issues have been raised regarding the membrane gas separation application including the trade-off between its permeability and selectivity and also its effects towards environment. Therefore, for this research, a biopolymer membrane for gas separation application will be developed with reasonably high on both permeability and selectivity. The main objective of this research is to study the effect of solvent evaporation time on the flat sheet asymmetric membrane morphology and gas separation performance. The membranes were produced by a simple dry/wet phase inversion technique using a pneumatically controlled casting system. The dope solution for the membrane casting was prepared by dissolving the cellulose acetate (CA) polymer in N-Methyl-2-pyrrolidone (NMP) and the solvent evaporation time was varied. Permeability and selectivity of the membrane was performed by using pure gases of carbon dioxide, CO2 and methane, CH4. The increase in solvent evaporation time had improved the membrane morphologies as the porosity of the membrane surface decrease and formation of a more mature skin layer. The gas permeation tests determined that increasing in solvent evaporation time had increased the selectivity of CO2/CH4 but reduce the permeability of both gases

Biodegradable Gas Separation Membrane Preparation by Manipulation of Casting Parameters

Poly(lactic acid) PLA that derived from renewable resources can help our society to reduce the dependence to non-renewable fossil resources. When come to human contact, this polymer and its degradation product are neither toxic nor carcinogenic to human body. The use of poly(lactic acid) (PLA), a biodegradable polymer, as a membrane material would assist the reduction of depending to petroleum-based polymer that will assist in disposal issues on non-biodegradable polymer. This study investigated the effect of evaporation time to the gas separation performance of PLA membrane. Membrane prepared from polymer solution consists of PLA and dichloromethane (DCM) as solvent was fabricated using pneumatically controlled casting system with dry/wet phase inversion method. Permeation test was conducted using pure oxygen and nitrogen gas. The results revealed that as the evaporation time increased, the pore size and surface porosity decreased, while the skin layer thickness increased. Although the morphology of the prepared membranes showed the desirable structure, the gas separation performance of the membrane prepared with polymer concentration of 15 wt% and 60s evaporation time was found to be promising but not yet commercially ready.

The Effect of Catalyst Loading (ni-ce/al2o3) on Coconut Copra Pyrolysis via Thermogravimetric Analyzer

The aim of this study is to investigate the influence of catalyst weight loading on pyrolysis of coconut copra via thermogravimetric analyser (TGA). The pyrolysis process is conducted up to 700 °C at a heating rate of 10 °C/min in nitrogen (N2) atmosphere flowing at 150 mL/min. The catalyst was successfully prepared via wet impregnation method, with alumina (Al2O3) used as support, while cerium (Ce) and nickel (Ni) act as promoter. The feedstock samples for TGA were prepared accordingly with biomass to catalyst weight loading ratio as follows: CC-1 (1 : 0.05), CC-2 (1 : 0.10), CC-3 (1 : 0.15), CC-4 (1 : 0.20), CC-5 (1 : 0.50), and CC-6 (1 : 1). For comparison, the pyrolysis of coconut copra without catalyst is also determined at the same operating condition and labelled as CC-7 (1 : 0). The TGA-DTG curves shows that, the presences of catalyst significantly affect the degradation rate of volatile matter than lignin degradation. In this study, the CC-3 sample has achieved high mass loss at 83.27 % and also high degradation rate at 0.0107 mg/s. For lignin decomposition, it shows that, CC-1 to CC-6 samples has achieved lignin mass loss percentage below 12.7 %. The non-catalytic sample (CC-7) has exhibited 80.33 % of volatile matter of mass loss and 13.92 % of lignin mass loss. The optimum catalyst loading was observed at 1 : 0.15 (CC-3) that work best to degrade volatile matter at highest mass loss, in which attributes to higher yield of pyrolysis oil.

The Influence of 90 Degree Bends in Closed Pipe System on the Explosion Properties Using Hydrogen-Enriched Methane

This work sought to evaluate the explosion severity on hydrogen enrichment in methane-air mixture explosion. For this purpose, different hydrogen mixture compositions ranges between 4 to 8% v/v were considered. This work was performed using CFD tool FLACS that has been well validated for safety studies on both natural gas/methane and hydrogen system. FLACS is used to validate the maximum pressure and flame speed predicted by the CFD tool for combustion of premixed mixtures of methane and hydrogen against the experimental data. Experimental work was carried out in a closed pipe containing 90- degree bends with a volume of 0.41 m3, operating at ambient conditions. From the experiment observation, it shown that the coupling effect of bending and thermal diffusivity gave the dramatic influent on explosion severity in hydrogen-methane/air at very lean concentration. However, simulation results showed that FLACs is under-predicting the overpressure at very lean concentration of hydrogen in methane/air mixtures. It can be said that lower hydrogen content in methane/air mixture limits the hydrogen diffusivity, leading to the decrease of the burning rate and flame speeds. It is also demonstrated that the presence of 90-degree bend in closed pipe system increases the simulated flame speeds to the factor of 2-3, as compared to the experimental data. There are significant discrepancies between experimental and simulation, however, the results seem conservative in general.

Fast Turbulent Flames in Duct -vented Gas Explosion

The influence of vent ducts on gas explosions was investigated with the aim of determining whether the use of larger area of the vent duct than the vent, would reduce the overpressure in vented duct explosion. A 0.2 m 3 cylindrical vessel was used with L/D (length to diameter) of 2, at the limit of applicability of current explosion venting design guidance. Only end ignition was considered in this study with a vent coefficient, K of 16.4. Methane/air mixtures over a range of equivalence ratio, Ф (0.68, 0.84 and 1.05) have been used. Results showed that while there is no significant difference in maximum pressure for larger vent duct as compared to a free discharge vent at lean mixtures, however, a significant increase of overpressure ∼ 1.4 bar was obtained in reactive mixtures i.e. Ф = 1.05. This was due to the high unburnt gas velocities induced in the vent duct by the most reactive explosion, creating very high turbulence levels at the vent duct inlet which gave rise to very fast flames and very high back pressures. Flame speeds in the vent duct of up to 500 m/s were measured for the most reactive mixture in the larger vent duct. The results were not predicted by the current US and European vent design guidance.

Mindel S-1000 Based Asymmetric Membranes for O2/N2 Separation: Effect of Polymer Concentration

Mindel S-1000 Based Asymmetric Membranes for O2/N2 Separation: Effect of Polymer Concentration Hasrinah Hasbullah, Ng Be Cheer, Norazana Ibrahim, Rafiziana Md. Kasmani, Roshafima Rasit Ali and Ahmad Fauzi Ismail Advanced Membrane Technology Research Centre (AMTEC), Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia. Faculty of Petroleum and Renewable Energy Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia. Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia. hasrinah@petroleum.utm.my

Pineapple peel fibre biocomposite: Characterisation and biodegradation studies

In this study, pineapple peel fibre (PAPF) based low density polyethylene (LDPE) biocomposites for green packaging was studied. The PAPF was first being treated with alkali before compounded with LDPE. The mixture was compounded using twin screw extruder and the test samples were prepared using hot press machine. The compatibility of the PAPF as biocomposites was observed through the characterisation analysis and thermal properties and also the biodegradation analysis. Melt flow index (MFI) analysis was conducted to determine the process ability of the biocomposites. As the fibre loading in the biocomposites increases, the MFI values were decreased. The amount of water absorption was increased with the increases of PAPF loading due to the higher cellulose content. Thermal stability studies of biocomposites were undergoing thermogravimetry (TGA) and differential scanning calorimetry (DSC) analysis. Melting temperature (Tm) for the biocomposite was determined from the DSC analysis while the degradation temperature was determined by using the TGA analysis. The thermal properties of PAPF biocomposites were more or less the same as the LDPE properties. The biocomposites was buried in the soil for a month and exposed to fungi environment for 28 d for biodegradation analysis and the highest PAPF/LDPE loading biocomposites degraded the most. Therefore, PAPF biocomposites was compatible for green packaging.