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The palm oil industry generates significant amounts of solid wastes. The solid wastes, also known as oil palm biomass, includes the trunk (OPT) and fronds (OPT) from the plantation, and empty fruit bunch (EFB), mesocarp fibre (MF) and palm kernel shell (PKS) from the processing mills. Oil palm biomass is not effectively recycled for other applications, and existing disposal practices can cause adverse impacts on the environment. As oil palm biomass is a readily available lignocellulosic biomass, it has the potential to be a low-cost feedstock for conversion into higher value products. The first part of this study provides a comprehensive review of utilisation of oil palm biomass for the production of biofuels, chemicals and biomaterials through direct utilisation and physical conversion, biochemical conversion, thermochemical conversion and synthesis of lignin-based materials. The second part of this study discusses the opportunity for biorefinery development based on existing bioproducts from oil palm biomass, for the production of advanced fuels and platform chemicals that have not been explored in oil palm biomass research. This study proposes integrated biorefinery concepts via the integration of existing oil palm biomass biorefinery products with thermochemical process for upgrading the bioproducts into higher values products. The high-value products integrated biorefinery products include advanced biofuels, fuel additives and platform chemicals. The integrated biorefinery development for oil palm biomass processing is expected to improve the economics of the production of biomass-derived renewable energy and enhance the sustainability of palm oil industry.

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The outlook of the production of advanced fuels and chemicals from integrated oil palm biomass biorefinery

An investigation on diffusion bonding of aluminum and magnesium using a Ni interlayer

Characterisation of microcrystalline cellulose from oil palm fibres for food applications

The growing concerns regarding fuel consumption within the aerospace and transportation industries make the development of fuel-efficient systems a significant engineering challenge. Currently, materials are selected because of their abilities to satisfy engineering demands for good thermal conductivity, strength-toweight ratio, and tensile strength. These properties make magnesium an excellent option for various industrial or biomedical applications, given that is the lightest structural metal available. The utilization of magnesium alloys, however, requires suitable welding and joining processes that minimizes microstructural changes while maintaining good joint/bond strength. Currently, magnesium are joined using; mechanical fastening, adhesive bonding, brazing, fusion welding processes or diffusion bonding process. Fusion welding is the conventional process used for joining similar metals. However, the application of any welding technique to join dissimilar metals presents additional difficulties, the principal one being; the reaction of the two metals at the joint interface can create intermetallic com pounds that may have unfavorable properties and metallurgical disruptions which deteriorates the joint performance. This chapter investigates the welding and joining technologies that are currently used to join magnesium alloys with emphasis on the development of multi-material structures for applications in the biomedi cal industries. Multi-material structures often provide the most efficient design solution to engineering challenges.

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Dissimilar Welding and Joining of Magnesium Alloys: Principles and Application

Nano-composite coatings have become the focus of widespread research in recent years due in part to their superior properties when compared to purely metallic films. The ben‐ efits of using these types of coatings include high-specific heat, optical non-linearity, nov‐ el magnetic properties, enhanced mechanical behavior (large hardness and wear resistance), and good corrosion resistance. This chapter presents a parametric study of electrodeposited nano-composite coatings for improved abrasive wear resistance. The fol‐ lowing physical parameters were investigated using a Taguchi L18 fractional factorial de‐ sign of experiments (DOEs): current density, pH, bath temperature, nano-particle concentration, and electrolyte agitation (stir rate). The results were evaluated using the signal-to-noise (S/N) ratio to develop a non-dimensional relationship between the physi‐ cal parameters and the abrasive wear resistance of the coating. The relationship showed that the abrasive wear resistance of the coating increases as the quantity of nano-particle in the solution and the agitation frequency increase. The analysis of variance (ANOVA) indicated that the particle concentration had the greatest significance to the wear resist‐ ance of the coating.

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Parametric Analysis of Electrodeposited Nano-composite Coatings for Abrasive Wear Resistance

Heat-treatment is a frequently used technique for modifying the physical and chemical properties of materials. In this study, the effect of heat-treatment on the mechanical properties, thermal stability and surface morphology of two types of electrodeposited coatings (pure-Ni and Ni/Al2O3) were investigated. The XRD analyses showed that the crystal structure of the as-deposited coating changes from slightly amorphous to crystalline as the heat-treatment temperature increases. The heat-treatment of both the pure-Ni and the Ni/Al2O3 coating caused an increase of the grain size within the coatings. However, the unreinforced Ni coating experienced a faster growth rate than the Ni/Al2O3 coating, which resulted in a larger average grain size. The temperature-driven changes to the microstructure of the coatings caused a reduction in the hardness and wear resistance of the coatings. The presence of nanoparticles within the Ni/Al2O3 coating can successfully extend the operational temperature range of the coating to 473 K by pinning grain boundaries.

Effect of Heat-Treatment on the Thermal and Mechanical Stability of Ni/Al2O3 Nanocrystalline Coatings

Historically, the roughening of the surface of sugarcane mill roller shells has been done by a shielded metal arc-welding process (SMAW), which is called “arcing” in the sugar industry. In this method, discrete weld globules are deposited on the grey cast iron mill roller shell surface, a process that has proven inefficient and expensive. In this investigation, the surface of the grey cast iron samples were sprayed using an electric wire arc-spraying machine. The coatings were characterized for their hardness, coefficient of friction, and corrosion resistance. A modified block and ring wear testing machine was used with bagasse as the counterface material to simulate the sucrose juice extraction process employed in the sugar cane industry. The results of the study indicated that an optimum coefficient of friction could be obtained while achieving satisfactory hardness and high corrosion resistance. Therefore, the results implied that arc spraying is a potential candidate to replace arcing in modifying the...

A Tribological Study for an Increased Coefficient of Friction in the Extraction of Sugarcane Juice

Dispersion-strengthened metal matrix composites are used extensively in the development of engineering components, due in part to their high strength-to-weight ratio, high-temperature stability, high creep resistance, high melting point, low density, and corrosion resistance The addition of a reinforcing phase has led to significant improvements in the mechanical properties of these alloys However, despite substantial improvements in the properties, the lack of reliable joining methods has restricted their full potential The differences in physical and metallurgical properties between the intermetallic phase and the matrix prevent the successful application of fusion welding processes, conventionally used for joining monolithic alloys Therefore, alternative techniques that prevent microstructural changes in the base metal are required Extensive scientific research has been conducted on joining metal matrix composites reinforced with hard intermetallic compounds In this study, transient liquid-phase (TLP) diffusion bonding was used to join two pieces of Al 6061 alloy containing 15 wt% of Al2O3 particles Examination of the joint region was achieved using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction The results indicate that the reactions between the reinforcements, the matrix, and the Ni interlayer lead to the formation of numerous intermetallic compounds in the joint region

Kavian O. Cooke

Papers

Dissimilar Welding and Joining of Magnesium Alloys: Principles and Application

Parametric Analysis of Electrodeposited Nano-composite Coatings for Abrasive Wear Resistance

Effect of Heat-Treatment on the Thermal and Mechanical Stability of Ni/Al2O3 Nanocrystalline Coatings

A Tribological Study for an Increased Coefficient of Friction in the Extraction of Sugarcane Juice

A comparative analysis of techniques used for joining intermetallic MMCs