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Abstract Malaysia and Indonesia are the largest producers of palm oil product. The palm oil industry has contributed the biggest income to the countries for many years. Moreover, palm oils has emerged as one of the most important oils in the world’s oils and the market of fats. About 90% of palm oil is used as food related products worldwide, and the other 10% is used for basic raw material for soap. There are more than a hundred palm oil processing mills in the two countries. As such, a lot of savings can be done by using the fiber and shell from the processing wastes as an alternative fuel for electricity generation for this industry. This paper deals with energy conversion from the fiber and shell of the industry wastes as an alternative energy source for the palm oil mill industry in the two countries mentioned. The study concentrates on using the fiber and shell obtained from the processing of palm oil as fuels for the boiler instead of fossil fuel. In addition, the possibility of excess air and fuel air ratio for the fiber and shell combustion process is also discussed. Furthermore, it has been found that the shell and fiber alone can supply more steam and electricity than is required. Some palm oil mills in Malaysia and Indonesia have applied this strategy successfully. The FELDA palm oil mill, with the capacity 30–60 tons FFB/h, in Sungai Tengi, Selangor, Malaysia has been selected for this research.

Abstract For many years, the cost of production has been the main barrier in commercializing biodiesel, globally. It has been well researched and established in the literature that the cost of feedstock is the major contributor. Biodiesel producers are forced to choose between edible and non-edible feedstock. The use of edible feedstock sparks concern in terms of food security while the inedible feedstock needs additional pretreatment steps. On the other hand, the wide availability of edible feedstock guarantees the supply while the choice of non-edible results in a non-continuous or non-ready supply. With these complications in mind, this review attempts to identify possible solutions by exploring the potential of waste edible oils and waste catalysts in biodiesel preparation. Since edible oils are available and used abundantly, waste or used edible oils have the potential to provide plentiful feedstock for biodiesel. In addition, since traditional homogeneous catalysts are less competent in transesterifying waste/used oils, this review includes the possibility of heterogeneous catalysts from waste sources that are able to aid the transesterification reaction with success.

Abstract Biodiesel is an unsurpassed alternative fuel source intended to extend the value to fossil fuels, and the longevity and cleanliness of diesel engines. It reduces the dependence on the foreign fuels and reduces the greenhouse gas emissions due to its closed carbon cycle. The plentiful advantages of biodiesel are overcome by few drawbacks such as the increase in the nitrogen oxide emission, its incompatibility with cold weather conditions, and the regular intervals of engine parts replacement such as fuel filters, fuel tanks and fuel lines due to clogging. There is a further scope for enhancement in fuel properties and to overcome the drawbacks by addition of nanoparticles as fuel additives. Recent researches on fuel additives indicated the inclusion of nano-sized particles (metallic, non-metallic, oxygenated, organic and combination) with diesel-biodiesel fuel emulsion. The results achieved demonstrated an improvement in the thermophysical properties, enhancement in the heat transfer rate, and stabilization of the fuel mixtures. Also, there was an increase in the engine performance parameters and reduction in the exhaust emissions depending on the dosage of nanofluid additives. This review paper includes the methods for preparation of nanofluids, the stability enhancement of nanofluids by various technique, several characterization methods to find the chemical bonding, nanoparticle shape, and size, dispersion of nano-additives in liquid fuel, the health effects, and applications of nanoparticles in the automotive industry. The numerous literature reviewed had some degree of indistinct and inconsistent outcomes. The experimental results from the various researchers were not generalized to reach a general accord regarding this innovative approach of fuel adulteration. The present work summarizes the literature from most recent articles on nanoparticles as a liquid fuel additive. The effect of dispersion of several nanoparticles on the enhancement in the performance characteristics and reduction in emission of a CI engine fuelled with diesel-biodiesel blends are discussed. The further scope suggests the development of an economically sustainable and feasible nanoparticle additive for diesel and biodiesel fuel. Nevertheless, few obstacles and challenges which have been recognized in this review must be addressed before they can be fully put into practice in the industrial applications.

Abstract The global plastic production increased over years due to the vast applications of plastics in many sectors. The continuous demand of plastics caused the plastic wastes accumulation in the landfill consumed a lot of spaces that contributed to the environmental problem. The rising in plastics demand led to the depletion of petroleum as part of non-renewable fossil fuel since plastics were the petroleum-based material. Some alternatives that have been developed to manage plastic wastes were recycling and energy recovery method. However, there were some drawbacks of the recycling method as it required high labor cost for the separation process and caused water contamination that reduced the process sustainability. Due to these drawbacks, the researchers have diverted their attentions to the energy recovery method to compensate the high energy demand. Through extensive research and technology development, the plastic waste conversion to energy was developed. As petroleum was the main source of plastic manufacturing, the recovery of plastic to liquid oil through pyrolysis process had a great potential since the oil produced had high calorific value comparable with the commercial fuel. This paper reviewed the pyrolysis process for each type of plastics and the main process parameters that influenced the final end product such as oil, gaseous and char. The key parameters that were reviewed in this paper included temperatures, type of reactors, residence time, pressure, catalysts, type of fluidizing gas and its flow rate. In addition, several viewpoints to optimize the liquid oil production for each plastic were also discussed in this paper.

The finite nature of fossil fuels necessitates consideration of alternative fuels from renewable sources. The term biofuel refers to liquid, gas and solid fuels predominantly produced from biomass. Biofuels include bioethanol, biomethanol, biodiesel and biohydrogen. Biodiesel, defined as the monoalkyl esters of vegetable oils or animal fats, is an attractive alternative fuel because it is environmentally friendly and can be synthesized from edible and non-edible oils. Here, we review the various methods for the production of biodiesel from vegetable oil, such as direct use and blending, microemulsion, pyrolysis and transesterification. The advantages and disadvantages of the different biodiesel-production methods are also discussed. Finally, we analyze the economics of biodiesel production using Malaysia as a case study.

In recent years, palm and jatropha biodiesels have been considered as potential renewable energy sources in Malaysia. Therefore, this experimental investigation was conducted to improve the blend of these two biodiesels (20% biodiesel blend, named P20 and J20, respectively) with the help of oxygenated additives. The comparative improvement of P20 and J20 blends with ethanol, n-butanol, or diethyl ether as additives was evaluated in terms of performance and emissions characteristics of a four-stroke single cylinder diesel engine. The final blend consisted of 80% diesel, 15% biodiesel, and 5% additive. Tests were conducted at different speeds (1200–2400 rpm) at constant full load conditions. Use of additives significantly improved brake power and brake thermal efficiency (BTE). Compared with P20 blend, the use of diethyl ether as additive increased brake power and BTE by about 4.10% and 4.4%, respectively, at 2200 rpm. A similar improvement was observed for J20. The other two additives also improved performance. Although HC emission increased slightly, all blends with additives reduced more NOx and CO emissions than P20 and J20 almost throughout the entire engine test. The use of ethanol as additive reduced CO emission by up to 40%, while the use of diethyl ether as additive reduced NOx emissions by up to 13%. The additives’ oxygen content, volatility, and latent evaporation heat controlled the emissions characteristics of the blends. An analysis of the combustion chamber pressure, temperature and heat release rate of the modified blends revealed interesting features of combustion mechanism, which are indicative of the performance and emissions characteristics. This experiment reveals the potential improvement of palm and jatropha biodiesel blends with the addition of three promising additives. 2014 Elsevier Ltd. All rights reserved.

Non-edible feedstocks are regarded as a sustainable source of renewable energy. In order to find renewable, cheaper and easier methods to obtain energy, attention has been paid to develop potential green catalyst to produce renewable biodiesel. The catalyst was characterized by X-ray diffraction (XRD) results in combination with thermogravimetry-differential thermal analysis (TG-DTA), Brunauer-Emmer-Teller (BET), Fourier transfrom-infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TEM analysis depicted that calcium. methoxide (Ca(OCH3)(2)) catalysts were in size of 34.7 nm. The reaction parameters namely; reaction time, methanol/oil molar ratio, catalyst dosage were investigated for fatty acid methyl ester (FAME) yield. The highest biodiesel yield (95%) was appraised under the optimum condition (i.e. catalyst amount of 2 wt.%; methanol/oil molar ratio of 15:1, reaction time of 90 min). The Ca(OCH3)(2) phase of catalyst can be regarded as an active phase to get high yield of biodiesel which was confirmed from characterization study. Furthermore, important fuel properties were also investigated and satisfied the ASTM D6751 and European 14214 biodiesel standards. Thus, Ca(OCH3)(2) catalyst prepared in this study was having efficient, low toxicity, cost effective and easy to prepare for green fuels production especially biodiesel. (C) 2014 Elsevier Ltd. All rights reserved.

In recent years, there have been growing interests in key areas related to global warming resulting from environmental emissions, and the diminishing sources of fossil fuel. The increased interest has led to significant research efforts towards finding novel technologies in clean energy production. Consequently, the merits of a thermo-electric generator (TEG) have promised a revival of alternative means of producing green energy. It is, however, impractical to account for the cost of thermal energy input to the TEG which is in the form of final waste heat. This is because the technology presents critical limitations in determining its cost efficiency nor its economic disadvantages. This paper reviews the principles of thermo-electric power production, as well the materials use, performance achieved, and application areas. The paper also takes a particular deliberation on TEG heat sinks geometries and categories. The review emphasizes more on the TEG performance while considering a number of heat sink parameters related to its performance.

Abstract Moringaceae is a monogeneric family with a single genus i.e. Moringa. This family includes 13 species. All these species are known as medicinal, nutritional and water purification agents. This study reports, for the first time, on characterization of the biodiesel derived from crude Moringa peregrina seed oil and its blends with diesel. The crude oil was converted to biodiesel by the transesterification reaction, catalyzed by potassium hydroxide. High ester content (97.79%) was obtained. M. peregrina biodiesel exhibited high oxidative stability (24.48 h). Moreover, the major fuel properties of M. peregrina biodiesel conformed to the ASTM D6751 standards. However, kinematic viscosity (4.6758 mm2/s), density (876.2 kg/m3) and flash point (156.5 °C) were found higher than that of diesel fuel. In addition, the calorific value of M. peregrina biodiesel (40.119 MJ/kg) was lower than the diesel fuel. The fuel properties of M. peregrina biodiesel were enhanced significantly by blending with diesel fuel. In conclusion, M. peregrina is a suitable feedstock for sustainable production of biodiesel only blended up to 20% with diesel fuel, considering the edibility of all other parts of this tree.