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Extensive application of metal powder, particularly in nanosize could potentially lead to catastrophic dust explosion, due to their pyrophoric behavior, ignition sensitivity, and explosivity. To assess the appropriate measures preventing accidental metal dust explosions, it is vital to understand the physicochemical properties of the metal dust and their kinetic mechanism. In this work, explosion severity of aluminum and silver powder, which can be encountered in a passivated emitter and rear contact (PERC) solar cell, was explored in a 0.0012 m3 cylindrical vessel, by varying the particle size and powder concentration. The Pmax and dP/dtmax values of metal powder were demonstrated to increase with decreasing particle size. Additionally, it was found that the explosion severity of silver powder was lower than that of aluminum powder due to the more apparent agglomeration effect of silver particles. The reduction on the specific surface area attributed to the particles' agglomeration affects the oxidation reaction of the metal powder, as illustrated in the thermogravimetric (TG) curves. A sluggish oxidation reaction was demonstrated in the TG curve of silver powder, which is contradicted with aluminum powder. From the X-ray photoelectron spectroscopy (XPS) analysis, it is inferred that silver powder exhibited two reactions in which the dominant reaction produced Ag and the other reaction formed Ag2O. Meanwhile, for aluminum powder, explosion products only comprise Al2O3.

The objective of this research is to investigate the performance of Nickel-Cerium/HZSM-5 catalyst on pyrolysis of sugarcane bagasse and kinetic analysis via thermogravimetric analyzer. The sample is pyrolyzed from 30 to 700 °C at multiple heating rates (5, 10, 20, and 30 °C/min) in a nitrogen environment. The HZSM-5 was used as a support, while nickel and cerium were impregnated as promoters via incipient wetness impregnation method. For catalytic samples, the catalyst to biomass ratio was fixed at 1:1. The kinetic analysis of non-catalytic and catalytic pyrolysis was performed using the Flynn-Wall-Ozawa and Coats-Redfern methods. The catalytic pyrolysis has achieved higher activation energy (2.87 – 68.92 kJ/mol) over conversion than the non-catalytic pyrolysis (24.20 – 122.33 kJ/mol) using the Flynn-Wall-Ozawa method. The reaction mechanism of non-catalytic and catalytic pyrolysis follows power law (n=1) and chemical reaction (n=2) respectively via the Coats-Redfern method.

The production of pure silver nanoparticles (Ag-NPs) with unique properties remains a challenge even today. In the present study, the synthesis of silver nanoparticles (Ag-NPs) from natural pullulan (PL) was carried out using a radiation-induced method. It is known that pullulan is regarded as a microbial polysaccharide, which renders it suitable to act as a reducing and stabilizing agent during the production of Ag-NPs. Pullulan-assisted synthesis under gamma irradiation was successfully developed to obtain Ag-NPs, which was characterized by UV-Vis, XRD, TEM, and Zeta potential analysis. Pullulan was used as a stabilizer and template for the growth of silver nanoparticles, while gamma radiation was modified to be selective to reduce silver ions. The formation of Ag-NPs was confirmed using UV–Vis spectra by showing a surface plasmon resonance (SPR) band in the region of 410–420 nm. As observed by TEM images, it can be said that by increasing the radiation dose, the particle size decreases, resulting in a mean diameter of Ag-NPs ranging from 40.97 to 3.98 nm. The XRD analysis confirmed that silver metal structures with a face-centered cubic (FCC) crystal were present, while TEM images showed a spherical shape with smooth edges. XRD also demonstrated that increasing the dose of gamma radiation increases the crystallinity at a high purity of Ag-NPs. As examined by zeta potential, the synthesized Ag-NP/PL was negatively charged with high stability. Ag-NP/PL was then analysed for antimicrobial activity against Staphylococcus aureus, and it was found that it had high antibacterial activity. It is found that the adoption of radiation doses results in a stable and green reduction process for silver nanoparticles.

In the present work, a thermal treatment technique is applied for the synthesis of CexSn1−xO2 nanoparticles. Using this method has developed understanding of how lower and higher precursor values affect the morphology, structure, and optical properties of CexSn1−xO2 nanoparticles. CexSn1−xO2 nanoparticle synthesis involves a reaction between cerium and tin sources, namely, cerium nitrate hexahydrate and tin (II) chloride dihydrate, respectively, and the capping agent, polyvinylpyrrolidone (PVP). The findings indicate that lower x values yield smaller particle size with a higher energy band gap, while higher x values yield a larger particle size with a smaller energy band gap. Thus, products with lower x values may be suitable for antibacterial activity applications as smaller particles can diffuse through the cell wall faster, while products with higher x values may be suitable for solar cell energy applications as more electrons can be generated at larger particle sizes. The synthesized samples were profiled via a number of methods, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). As revealed by the XRD pattern analysis, the CexSn1−xO2 nanoparticles formed after calcination reflect the cubic fluorite structure and cassiterite-type tetragonal structure of CexSn1−xO2 nanoparticles. Meanwhile, using FT-IR analysis, Ce-O and Sn-O were confirmed as the primary bonds of ready CexSn1−xO2 nanoparticle samples, whilst TEM analysis highlighted that the average particle size was in the range 6−21 nm as the precursor concentration (Ce(NO3)3·6H2O) increased from 0.00 to 1.00. Moreover, the diffuse UV-visible reflectance spectra used to determine the optical band gap based on the Kubelka–Munk equation showed that an increase in x value has caused a decrease in the energy band gap and vice versa.

Jet fires are a type of dangerous fire caused by the sudden release of flammable materials. In this work, propane was used as fuel and released through a 7.15mm and 9.8 mm circular nozzle with the exit velocities were set ranging between 27 and 65 m/s. The data of this study are compared against theoretical measurement and prediction using previously suggested correlation for projected flame length and flame extension length. It was determined, the projected flame length gives a good prediction by using theoretical measurement while for the prediction of flame extension length, an elliptical shape assumption was suitable to be used after impinging point for a horizontal buoyant jet fire.

Polysulfone (PSf) membranes are becoming more popular in wastewater treatment recently, mostly due to its stability in chemical, thermal and mechanical properties. PSf membranes are hydrophobic, causing difficulty of water permeation. Incorporating metal oxide nanoparticles improving the membrane hydrophilicity, thus increasing membrane permeation and rejection. In this study, copper oxide nanoparticle (CuO NPs) incorporated PSf membranes were fabricated under different evaporation times of 3s, 6s, 8s, and 9s to investigate on membrane morphology and performance. The membrane morphologies were characterized by using scanning electron microscope (SEM) while the membrane performance was determined through pure water flux (PWF) and bovine serum albumin (BSA) rejection. When characterized by SEM, all membranes showed an asymmetric structure with thin and dense at the top while the bottom layer was thick and porous. It was discovered that as the evaporation time increased, the formation of the finger-like structure became narrower while dense layer became thicker. When tested with PWF, membranes with higher evaporation times showed less permeability, decreasing from 139.74 Lm-2h-1 to 89.89 Lm-2h-1. In terms of BSA rejection, increased in evaporation time caused the rejection rate to increase from 87.79% to 92.15%. This study proved that evaporation time is one of important parameters that influences the membrane performance significantly.

Dust explosion is considered as a serious threat for the industry that use or handle combustible materials as it may lead towards a significant economic loss in terms of damage to the facilities and suspension of activities, severe workplace injuries and fatalities. The rapid pressure developed during a dust explosion can be mitigated by venting. The present work explored the effects of venting on the explosion of different mixing weight ratios of aluminium and silver powder mixtures. The explosion characteristics of aluminium-silver mixtures were assessed in a 0.0012 m3 confined and vented cylindrical vessel. It was found that the application of 0.1 bar static burst pressure (Pstat) venting membrane gives one tenth reduction on explosion pressure and maximum rate of pressure rise for 70:30 and 50:50 mixing weight ratios of aluminium-silver mixtures explosion, respectively. This finding suggests that besides the venting application effect, the oxidation reaction of aluminium could be disrupted due to the presence of silver powder in the metal mixtures which results in lower heat transfer and reduction of the mass burning rate, hence, lessen flame speeds and explosion severity. However, the venting effectiveness is reduced when the Pstat increases. In order to assess the applicability of the dust explosion venting standard; NFPA 68 and EN 14491, the experimental results were compared with the calculated values according to the standards. The comparative results show that, both NFPA 68 and EN 14491 give underestimated values for explosion venting as compared with the experimental results.

The main objective of the present work is to investigate the influence of nickel to cerium ratio on Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5) towards the catalytic upgrading of sugarcane bagasse derived oxygenated pyrolysis vapours into C6 – C8 hydrocarbons in pyrolysis oil via in-situ fixed bed reactor. The pyrolysis reaction temperature and catalyst to biomass mass ratio were kept constant at 500 °C and 1:1 respectively for all the investigated samples. The HZSM-5 was used as a support at 94 wt.%, while the balance 6 wt.% was impregnated with various weight of nickel and cerium as promoters based on the nickel to cerium ratios via incipient wetness impregnation method. The nickel to cerium ratios are as follows: 1:5 (NC1), 2:4 (NC2), 3:3 (NC3), 4:2 (NC4), and 5:1 (NC5). The results show that all the metal modified HZSM-5 catalysts had greatly suppressed the formation of coke contents (9.0–10.5 wt.%) compared to the HZSM-5 catalyst (NC0) (15.1 wt.%). The highest pyrolysis oil yield (60.5 wt.%) was achieved by NC2 catalyst. Among the tested nickel to cerium ratios, the NC3 catalyst has demonstrated to be the potential candidates in the catalytic upgrading of sugarcane bagasse derived oxygenated pyrolysis vapours into higher contents of C6 – C8 hydrocarbons in pyrolysis oil (8.82%).

The main objective of the current work is to investigate the influence of catalyst to biomass ratio (by weight%) on the catalytic upgrading of sugarcane bagasse derived pyrolysis vapours over cerium (Ce) loaded Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5) catalyst via in-situ fixed bed reactor. The temperature of pyrolysis was kept at 500 °C for all investigated samples. The HZSM-5 catalyst was used as a support with 1 wt% of Ce as promoter loaded via incipient wetness impregnation method. The biomass sample was fixed at 2 g, while the catalyst mass loading was loaded according to the catalyst to biomass ratio which are 0.5:1.0, 1.0:1.0, 1.5:1.0, and 2.0:1.0. For comparison, the non-catalytic and biomass catalytic over HZSM-5 catalyst was also pyrolyzed at the same operating conditions. The results show that the yields of pyrolysis oil and coke were significantly influenced by the use of Ce/HZSM-5 catalyst at various catalyst to biomass ratio than the catalytic pyrolysis over HZSM-5, in which generate higher pyrolysis oil yield (58.0–68.0 wt%) and lower coke yield (2.9–4.1%). The increasing loading of mass in Ce/HZSM-5 catalyst has additional effect with respect to C6–C8 hydrocarbon contents in pyrolysis oil than the catalytic samples over the HZSM-5 catalyst. Among the tested catalyst to biomass ratio, the catalyst to biomass ratio of 1.5:1 has demonstrated to be the potential candidates in the catalytic upgrading of sugarcane bagasse derived oxygenated pyrolysis vapours into higher content of C6–C8 hydrocarbons (2.45%) in pyrolysis oil with lower coke yield (3.2%) over Ce/HZSM-5 catalyst. The bi-functional Ce/HZSM-5 catalyst was more effective in suppressing the coke formation in comparison to HZSM-5 catalyst at all investigated catalyst to biomass ratios and this was attributed to the synergistic effect of Ce on HZSM-5 support.

The main objective of the present work is to investigate the influence of catalyst to biomass ratio (C:B) on pyrolysis sugarcane bagasse over cerium loaded Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5, Si/Al = 23) catalyst via in-situ fixed bed reactor. HZSM-5 catalyst was used as a support with 1 wt.% of Ce as promoter loaded via incipient wetness impregnation method. The pyrolysis oil (PO) yield and coke yield were significantly affected by the use of Ce/HZSM-5 at various C:B ratio than the none catalytic pyrolysis, in which generating low PO yields (50.0 wt.%). The increasing Ce/HZSM-5 loading has an additional effect with respect to PO and coke yields. Among the tested C:B ratio, a catalyst to biomass ratio of 1:1 has demonstrated to be potential candidates in the catalytic pyrolysis of SB into a higher yield of condensable pyrolysis oil with lower coke contents.

The main objective of the present work is to study the effect of molybdenum (Mo) loading amount on Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5, Si/Al = 23) catalyst on pyrolysis of sugarcane bagasse via in-situ fixed bed reactor. HZSM-5 zeolite catalyst was used as a support with Mo as promoter modified at varying metal loading (0.5, 1.0 and 1.5 wt.%) via incipient wetness impregnation method. The pyrolysis oil (PO) yields and aromatic hydrocarbons (AHCs) yields were significantly affected by the use of all synthesized catalysts than the none catalytic pyrolysis, in which generating lower PO yields (11.7 wt.%) and AHCs yields (1.1 wt.%). The impregnation of Mo in the framework of HZSM-5 has an additional effect on the performance of the support HZSM-5 catalyst, with respect to PO and AHCs yields. Among all the catalysts tested, Mo(1 wt.%)/HZSM-5 catalyst has demonstrated to be potential candidates in the catalytic pyrolysis of sugarcane bagasse into a higher yield of ACHs in PO.

The main objective of the present work is to study the effect of Nickel-Cerium/Alumina multifunctional catalyst (Ni-Ce/Al2O3) mass loading on pyrolysis of coconut copra and rice husk via thermogravimetric analysis. The sample is pyrolyzed from 30 °C up to 700 °C at a constant heating rate of 10 °C/min in nitrogen environment flowing at 150 mL/min. The multifunctional catalyst (Ni-Ce/Al2O3) was prepared via incipient wet impregnation method. Pyrolysis feedstocks were prepared based on biomass to catalyst mass loading ratio. The TG-DTG curve shows that the presences of catalyst significantly affect the devolatilization rate of biomass. Among TGA-pyrolyzed coconut copra samples, the CC-3 (1:0.15) has achieved the highest mass loss (83.3%). For rice husk, the non-catalytic sample has attained the highest mass loss of volatile matter (48.7%). In addition, the kinetic characteristics of non-catalytic and catalytic pyrolysis of biomass were also studied and calculated by employing the Coats-Redfern integral method. The CC-1 has lower activation energy (53.10 kJ/mol) than that of catalytic sample particularly CC-3 (79.28 kJ/mol). The presence of a catalyst on rice husk is able to reduce the activation energy of non-catalytic rice husk sample from 49.78 to 45.24 kJ/mol.

The benefits of using hydrogen as a source of fuel seem to be limited due to a number of difficulties. To overcome the drawbacks of hydrogen, hydrocarbon-hydrogen fuel mixtures are the best substitutions. However, in literature, the flame acceleration of hydrogen-hydrocarbons/air mixtures in tee pipes has not yet been fully explored. Thus, the aim of this work is to report some new experimental data and provide an understanding of the explosion development in the geometry of tee pipes. In this study, premixed C2H4-H2/air, NG-H2/air and C3H8-H2/air mixtures with different ratios of 10:90, 30:70, 50:50, 70:30 and 90:10 were ignited at six ignition positions at two tee pipe configurations. Hydrocarbon fuels were considered as the primary gases. For the overall observation, it can be said that the flame reactivity of ethylene-hydrogen/air and NG-hydrogen/air was much higher. The kinetic reaction of these mixtures contributed to the overall explosion development. However, the dynamics of flame deployment in the tee junctions had a significant effect on the recorded maximum overpressure and flame speeds along the pipes. Moreover, the obtained data show that the lower distance of tee junction to ignition point caused a higher explosion severity in terms of the rate of pressure rise.

This paper reports on the experimental and numerical analyses towards understanding the flame propagation in hydrogen and methane explosions, with the effect of pipe configurations. The experimental works were performed in a straight and 90-degree bend pipe with the length to diameter ratio, L/D is 51. FLACs code simulation was adopted to investigate the dynamic of flame behaviour in both pipe configurations. From the results, it was observed that the presence of 90-degree bend enhances the explosion severity by a factor of 1.03-3.58 as compared to that of the straight pipe. Based on the simulation analysis, the compression effect at the bending region and at the end of the pipe plays an important role to attenuate the burning rate, which results to the increase of the pressure wave. Furthermore, compression effect is the main mechanism for the flame to propagate and potentially lead to a catastrophic explosion.

Explosions caused by the rapid release of energy from the expansion of burnt gases, along with an associated pressure rise, in an enclosure can be mitigated by venting. Many empirical equations have been derived based on vented gas deflagration phenomena. In the present paper, four empirical equations for gas venting were reviewed, i.e., NFPA 68, the European Standard (EN 14994), Molkov et al. and Bradley and Mitcheson in order to assess their reliability and applicability for predicting the reduced explosion pressure (Pred) of propane-air, methane-air and hydrogen-air mixtures at three different chamber-scale volumes. The results showed that the NFPA 68 correlation is the most appropriate method for predicting Pred, while Bradley and Mitcheson gave values closer to those of experimental data for propane-air mixtures in medium and larger chambers, respectively. However, none of the predicted correlations was able to provide a reasonable prediction of Pred in a hydrogen-air explosion. In addition, these predicted correlations showed greater discrepancies in Pred values in the presence of vent area, ignition position and obstacles.

Biocomposite has been widely used as plastics replacement for its biodegradability. However, the water absorptivity defeats its purpose as food packaging. The water absorption analysis for pineapple peel fiber (PAPF) was done according to ASTM D570-98 and it has been proven that the water content increases to 7.2% with the 50% content of PAPF in the bio-composite (50% PAPF). For that matter, hydrophobic coating was synthesized and applied on PAPF based bio-composite. The bio-composite was produced using Low Density Polyethylene (LDPE), pineapple peel fibre (PAPF), Linear LDPE grafted maleic anhydride (LLDPE-g-MA) as compatibilizer and Refined, Bleached Deodorized Olein (RBDOL) as plasticizer. The coating was synthesized by using polydimethylsiloxane (PDMS) and decamethylcyclopentasiloxane as hydrophobic component, silica nano-particles as nanostructured particles and non-organic solvent and non-ionic surfactant p-octyl polyethylene glycol phenyl ether as surfactant. The emulsion was homogenized and after that sprayed onto the surface of PAPF bio-composite and dried in the oven at 50-60˚C for 24 hours. Through the 100µm magnification using field emission scanning electron microscope (FESEM), the hydrophobic coating was proven to conform the Cassie-Baxter hydrophobic property. C-O bond from the PAPF disintegrates after the production of bio-composite from the Attenuated Total Reflectance Fourier Transform Infrared (ATR FTIR) spectrometry transmittance. The application of the coating onto the surface of PAPF bio-composite gave the surface hydrophobic property where the contact angle changes from 82.27±2.66˚ which is hydrophilic to 122.63±2.17˚ which is hydrophobic. The bio-composite with the highest PAPF content will also exhibit self-cleaning ability which makes it suitable for the usage of hydrophobic food packaging material.

In this work, thermal degradation behavior of six local biomasses such as empty fruit bunch, rice husk, coconut pulp, saw dust, coconut shell, and sugarcane bagasse in Malaysia via pyrolysis was studied. The pyrolysis process was carried out from 25 to 700 °C under nitrogen atmosphere flowing at 150 ml/min via a thermogravimetric analyzer. The effect of biomass type was investigated on pyrolysis behavior. The particle size of biomass was in the range of 0.3 ≤ dp1 < 0.5 mm, whereas the heating rate was fixed at 80 °C/min. The thermogravimetric analysis (TGA) data were divided into three phases of degradation: moisture evolution, hemicellulose-cellulose degradation, and lignin degradation. The results showed that all biomass samples degraded between 25 and 170 °C in Phase I of moisture evolution. Among the biomass samples, coconut pulp achieved the highest mass loss (81.9%) in Phase II of hemicellulose-cellulose degradation. Lignin in all biomass samples gradually degraded from 450 to 700 °C in Phase III of lignin degradation. This study provides an important basis in understanding the intrinsic thermochemistry behind degradation reactions.

A new corrosion control system which is biological cathodic protection (CP) system was developed using the concept of microbial fuel cells (MFCs). Microorganisms available in domestic wastewater was utilised to generate electrons and supplied to the carbon steel pipe, and as consequence, protect the pipe from corrosion. There are various factors affect the performance of the system including the pH at the anode and cathode chamber. This study aims to analyse the optimum pH at anode and cathode. In this study, wastewater was used as the electrolyte and graphite rod as the electrode in the anode compartment while cathode compartment was filled with sand and carbon steel pipe acts as the cathode. Both compartments were connected by a plastic tubing and separated by the membrane. It was found that optimum pH at anolyte and catholyte were 8 and 6. The CP potential versus copper sulfate electrode (CSE) was -752 mV. It shows that the corrosion of carbon steel pipe was reduced since the native potential of the carbon steel pipe versus CSE was -560 mV.

In this study, the concept of Microbial Fuel Cells (MFCs) was applied in the biological cathodic protection (CP) system in order to protect steel pipe. There are various factors affect the performance of the system including the volume of the medium.The purposes of this study were to analyse and optimise the effect of volume ratio of wastewater to the sand on biological CP performance by using Taguchi method. The maximum performance of biological CP in this study was obtained at the largest volume ratio. The orthogonal array and the signal-to-noise ratio (S/N) were employed to study the effect of volume ratio on performance of biological CP. The CP potential vs. copper sulfate electrode (CSE) was -835 mV. It shows that the corrosion of carbon steel pipe was reduced since the native potential of the carbon steel pipe vs. CSE was -531 mV.

This paper deals with the assessment of external explosion, resulting from accidental release of jet fuel from the large commercial airliner in the nuclear power plant (NPP). The study used three widely prediction methods such as Trinitrotoluene (TNT), multi energy (TNO) and Baker-strehow (BST) to determine the unconfined vapour cloud explosion (UVCE) overpressure within the distances of 100-1400 m from the first impact location. The containment building was taken as the reference position. The fatalities of persons and damage of structures was estimated using probit methodology. Analysis of the results shows that both reactor building and control-room will be highly damaged with risk consequences and probability, depending on the assumed position of the crash. The structures at the radial distance of 600 m may suffer major structural damage with probability ranging from 25 to 100%. The minor structural damage was observed throughout the bounds of the plant complex. The people working within 250 m radius may get affected with different fatality ranging from 28 to 100%. The findings of this study is valuable to evaluate the safety improvement needed on the NPP site and on the risk and consequences associated with the hydrocarbon fuel release/fires due to external hazards.

Objective: This paper scrutinizes the available literature and presents a comprehensive overview of nuclear fire safety, acknowledging some areas for future research. Methods/Statistical Analysis: Relevant literatures on the aircraft impact upon nuclear reactor containment were reviewed. Scope, findings and limitations of major researches in this field were presented and possible areas of future research were highlighted. A statistical analysis on the number of scientific publications on nuclear fire safety per five years which present the progress in the subject matter was reported. The analysis considered 1968 and 2015 as the base and end years respectively. Findings: In general, some of the identified challenging issues and limitations of nuclear fire studies are: (i) there are limited experimental data on real nuclear fire (ii) studies which considered the impact of external events like aircraft crash on containment gave little or no considerations to tendon gallery, openings and penetrations as in most cases, crash were hypothetically assumed to occur at the midpoint of the cylindrical portion of the containment and near the junction of dome without making recourse to the other portions of the containment e.g. roofing and reactor base (iii) Most reactor fire analysis do not consider material properties at elevated temperatures (iv) in the hazard analysis concerning aircraft impact, assessment of hazards from fireball and pool fire are yet to be fully considered (v) there are very limited data concerning structural failure modes caused by nearfield explosive loading. Application/Improvement: The findings of this article could be used to improve the existing methodologies of nuclear fire safety assessment in order to address some of the identified challenging issues.

Duct venting is the most recognized explosion protection technique used in the industry. However, the key problem with this technique is the appropriate design of the duct size for an effective release material to prevent the secondary explosion that can cause further damage to the plant. Factors such as duct length and diameter have a significant effect on the duct venting mechanism that contributes to the second explosion. Thus in this study, the duct-vented gas explosion was simulated with the aim to investigate the influence of duct length focusing on the flame and pressure characteristics. From the simulation analysis, it shows that vessel interconnected with the duct with 0.05 m diameter and 0.5 m length experience a flame severe problem behavior to produce the secondary explosion effect.

Flame propagation in the interconnected pipe with various size has a potential to initiate an explosion hazard. Thus in this study, the biogas/air flame propagation was investigated in the interconnected pipe. The experiment was conducted in pipe interconnected with three different diameters which are 5 cm, 10 cm and 46 cm respectively. The biogas is mixed with the ratio of 60:40 of methane and carbon dioxide. The concentration of biogas/air was varied at ER: 0.8 - 1.4 respectively. The mixtures were ignited using a spark plug. The pressure and flame speed were measured using thermocouples K type and pressure transducers located along the rig. Pure methane was also tested to examine the effect of CO2 on the biogas flame propagation. From the experimental analysis, the highest maximum overpressure (2.5 bar) and flame speed (41.9 m/s) were recorded at the smallest pipe diameter (0.5 cm) at rich concentration, ER= 1.2 and 1.4 respectively. The results show that the thermal diffusive effect is one of the factors contributed to the flame propagation that resulted to the increase of the maximum overpressure and flame speed. However, the presence of CO2 in biogas makes the biogas explosion is less severe as compared to the methane.

Pyrolysis is a viable solution to curb the issue of growing lignocellulosic waste in the world through conversion to potential biofuel and bio-based chemicals. This study focused on the effect of biomass particle size on the feedstock characterisation, biomass ash content, thermal behaviour and pyrolysis products yield. The particle size ranges studied were

Non-woven fibrous filter media from empty fruit bunches were fabricated by using chitosan as a binder. Chitosan powder was dissolved in a 1 wt% aqueous acetic acid, and 1 wt% to 4 wt% of chitosan solutions was prepared. Chitosan-filled empty fruit bunches filter media have been prepared via wet-layup method. Thermogravimetric analysis (TGA) was performed to study various thermal properties of the fibrous filter media. It was found that the fibrous filter media have undergone several decomposition stages over a range of temperatures as revealed by TGA thermo-grams, where the temperature for 10% weight loss for chitosan-filled EFB filter media and binder-less filter media was at 150oC and 300oC, respectively., {"references":["Treviño-Cordero, H., et al., \"Synthesis and adsorption properties of activated carbons from biomass of Prunus domestica and Jacaranda mimosifolia for the removal of heavy metals and dyes from water,\" Industrial Crops and Products, 2013. 42(1): p. 315-323.","Abdullah, M.A., A.U. Rahmah, and Z. Man, \"Physicochemical and sorption characteristics of Malaysian Ceiba pentandra (L.) Gaertn. as a natural oil sorbent,\" Journal of Hazardous Materials, 2010. 177(1-3): p. 683-691.","Kyzas, G.Z., N.K. Lazaridis, and M. Kostoglou, \"Modelling the effect of pre-swelling on adsorption dynamics of dyes by chitosan derivatives,\" Chemical Engineering Science, 2012. 81: p. 220-230.","Shin, E.W., K.G. Karthikeyan, and M.A. Tshabalala, Adsorption mechanism of cadmium on juniper bark and wood. Bioresource Technology, 2007. 98(3): p. 588-594.","Vlaev, L., et al., Cleanup of water polluted with crude oil or diesel fuel using rice husks ash. Journal of the Taiwan Institute of Chemical Engineers, 2011. 42(6): p. 957-964.","Rengasamy, R.S., D. Das, and C. Praba Karan, Study of oil sorption behavior of filled and structured fiber assemblies made from polypropylene, kapok and milkweed fibers. Journal of Hazardous Materials, 2011. 186(1): p. 526-532.","Ali, N., et al., Characteristics and oil sorption effectiveness of kapok fibre, sugarcane bagasse and rice husks: Oil removal suitability matrix. Environmental Technology, 2012. 33(4): p. 481-486.","Lee, S.A. and M.A. Eiteman, Ground kenaf core as a filtration aid. Industrial Crops and Products, 2001. 13(2): p. 155-161.","Ahmad, T., et al., Oil palm biomass-based adsorbents for the removal of water pollutantsa review. Journal of Environmental Science and Health - Part C Environmental Carcinogenesis and Ecotoxicology Reviews, 2011. 29(3): p. 177-222.\n[10]\tAhmad, T., et al., The use of date palm as a potential adsorbent for wastewater treatment: A review. Environmental Science and Pollution Research, 2012. 19(5): p. 1464-1484.\n[11]\tHan, J.S., et al. Removal Of Phosphorus Using Chemically Modified Lignocellulosic Materials. in 6th Inter-Regional Conference on Environment-Water \"Land and Water Use Planning and Management\". 2003. Albacete, Spain.\n[12]\tHan, J.S., S.-H. Min, and Y.-K. kim, Removal ofmaterial. Forest Products Journal, 2005. 55(11): p. 48-53.\n[13]\tHan, J.S. Stormwater Filtration Of Toxic Heavy Metal Ions Using Lignocellulosic Materials Selection Process, Fiberization, Chemical Modification, And Mat Formation. in 2nd Inter-Regional Conference on Rnvironment-Water 99. 1999.\n[14]\tKim, R.H., et al., Reuse of greywater and rainwater using fiber filter media and metal membrane. Desalination, 2007. 202(1-3): p. 326-332.\n[15]\tHussein, M., A.A. Amer, and I.I. Sawsen, Oil spill sorption using carbonized pith bagasse: trial for practical application. International Journal Science Technology, 2008. 5(2): p. 233-242.\n[16]\tJulkapli, N.M. and H.M. Akil, Thermal Properties of Kenaf-Filled Chitosan Biocomposites. Polymer-Plastics Technology and Engineering. 49(2): p. 147-153."]}

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.

The aim of this study is to investigate the thermal degradation behaviour of oil palm trunk (OPT) and empty fruit bunch (EFB) wastes in pyrolytic environment by using thermagravimetric analyzer (TGA). The pyrolysis process was being carried out at room temperature up to 700°C in the presence of nitrogen gas flowing at the rate of 150ml/min. The investigated parameters are particle sizes and heating rates. The particle sizes varied in the range of dp1 < 0.25mm and 0.25 ≤ dp2 ≤ 0.30mm. The heating rate of 50°C/min and 80°C/min were applied to study the effect on thermal degradation during the progress of pyrolysis reaction. The decomposition of OPT shows a ‘shoulder’ form while EFB degrades with 2 distinctive peaks. Smaller OPT size produces 0.04-0.86% more volatile product when degraded at both heating rates. EFB on the other hand shows a 3.81-9.81% increment. Heating rates speed up the peak degradation by 1.42-1.56mg/s at dp1 and 3.13-4.92mg/s at dp2. It also causes biomass to be degraded under a narrow temperature range by 21°C. This study can provide an important basis in determining suitable type of feedstock and processing parameters for bio-fuel production via advanced pyrolysis technology.