Key Engineering Materials Vol. 974

Abstract: Freshwater is essential in sustaining human life on the planet and the demand for potable water has increased for the past years due to population growth and modernization. However, the natural resources of water have become polluted/contaminated due to industrialization and other human activities. The development of membrane technology, especially with the creation of nanocomposite materials, provides a solution to treat polluted or contaminated water through various separation processes resulting in the production of clean water fit for human consumption. In this study, polysulfone was added with zeolite nanoparticles to fabricate nanocomposite membranes via non-solvent induced phase separation (NIPS) method to enhance the hydrophilicity and mechanical strength of the membrane suitable for water and wastewater applications. The nanozeolite was added in varying concentrations; 1% 5% and 10% and the fabricated membranes were characterized via Contact Angle Goniometer, universal testing machine (UTM) and scanning electron microscopy (SEM) to determine the contact angle, tensile strength, and surface morphology, respectively. Based on the characterization data, the 1% concentration showed the highest tensile strength and the lowest contact angle measurement. The 1% nanozeolite concentration is the optimum membrane formulation due to the enhanced hydrophilicity and mechanical strength of the material.

Abstract: This study describes the sol-gel method's synthesis of ferrites [MFe₂O₄, M(II) = Co, Cu, Mg, Ni, and Zn]. The structure was studied by X-ray diffraction analysis. The surface morphology was studied using scanning electron microscopy (SEM), and the magnetic properties were studied using Mössbauer spectroscopy. The diffraction peaks at 30.1^◦, 35.6^◦, 43.2^◦, 53.6^◦, 57^◦, and 62.6◦ can be attributed to Bragg reflections (2 2 0), (3 1 1), (4 0 0), (4 2 2), (5 1 1), and (4 4 0) planes confirm the formation of a cubic spinel structure of ferrite nanocrystals. The average size of magnesium ferrite crystallites calculated from the half-width of the most intense peak (3 1 1) was 25.96 ± 4.32 nm. Magnesium ferrite is a magnetically soft ferromagnetic powder with a predominance of the magnetite phase and relatively high magnetisation values. The magnitude of the hyperfine magnetic field for the studied nanoparticles is in the range of 440-490 kOe, which confirms the hypothesis that the analysed samples are particles of an iron-containing oxide with a disordered structure.

Abstract: The use of blended palm biodiesel has been implemented in Malaysia starting with B5 (5% palm biodiesel blended with 95% petroleum diesel) in 2011, B7 (7% palm biodiesel blended with 93% petroleum diesel) in 2014, and B10 in 2019. Palm biodiesel has been regarded as a reliable petroleum diesel substitute since 1995 following the research and development carried out by MPOB. Six trucks participated in the trial to evaluate the use of B20 and B10 through fleet testing and laboratory investigations. The trucks were divided into two groups according to fuel used. The field trial started in 2019 and ended in 2021. Engine oil and filter samples were taken at 5,000 kilometers intervals between service interval 30,000 kilometers. All the engine oil samples were within their operational service limits at each 5,000 kilometers sampling interval. The average viscosities of used engine oil in B20 group were 12.75 mm² s^-1 and for B10 group 12.98 mm² s^-1. The total basic number (TBN) values for the B20 group was 6.4 mg KOH g^-1 and 6.3 mg KOH g^-1 on average for B10 group. The wear and contaminants test showed the average iron particles concentrations for B20 and B10 groups were 22 ppm and 25 ppm respectively. In terms of engine oil evaporation, the average zinc and phosphorus concentrations reduced by only 20% for both vehicle groups. The average values for soot in oil showed that the B20 group had 10% less soot build-up compared to B10 group. The use of B20 had affected engine oil quality with minimal advantages for soot in oil and iron particle concentrations.

Abstract: In recent years, biodiesel has emerged as a popular alternative to fossil fuels due to its superior properties. However, the presence of bioactive compounds, known as sterol glucosides (SGs), in crop-based biodiesel has posed a challenge for producers, as they act as crystal seeds and can cause gel formation or precipitation in cold temperatures. This can lead to issues with the quality of biodiesel during storage or use in vehicle engines. To address this issue, a study was conducted to explore the use of silica-based materials as an adsorbent to reduce SGs concentration in palm oil biodiesel. Natural resources silica material with a size of less than 100 µm was used in the process. The results showed that the use of silica gel led to the removal of 63.09 % of SGs in palm-based biodiesel due to its high surface area (556 m²/g) and porosity (0.79 cm³/g). Fourier transform infrared spectroscopy (FTIR) analysis indicated that the silicate and hydroxyl groups on the adsorbent’s surface were responsible for SGs adsorption. Importantly, the quality of the biodiesel before and after the adsorption treatment met all the specifications of the EN 61214 standard. This research suggests that the use of silica-based materials could be a promising solution for reducing SGs concentration in crop-based biodiesel, and could potentially improve its overall quality.

Abstract: There are many facets to the applications of Artificial Intelligence (AI) in the energy sector however, this research focuses on the utilization of Artificial Neural Networks (ANN) as parts of AI technique to simulate and model the operating performance of an industrial biogas plant data set. In this study, eight (8) model network architectures were developed using the ANN tool of MATLAB 2016a version and it was found that the best result was obtained based on the model performance evaluation metrics used such as Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), Mean Absolute Deviation (MAD) and Determination Coefficient (R²) was as a result of the combination of two activation functions namely: tansig and logsig. The model, that produced the best result was a result of the architecture that contains 2 hidden neurons and the training algorithm of Scaled Conjugate Gradient (SCG). It was also observed that the ANN-predicted network diagram is better than the observed.

Abstract: This research presents the production of biodiesel from nonedible, renewable ackee apple seed oil and its characterization. The study was carried out on trans-esterification of oil with methanol and sodium hydroxide as catalyst for the production of biodiesel. The harvested ackeed seed was sundried crushed manually and oven dried at a temperature of 105 for 24 hours 250g each of milled ackee seeds were respectively placed in the thimble of a Soxhlet extractor with the use of about 800ml of n-hexane., the flask was heated at 60 with the use of an electric mantle. As the solvent was heated in the boiler, the pure vapor rose through a by-pass and into the top part of the container where the sample to extract was contained. In the condenser, the vapors condensed and drip into the sample-containing thimble.The process parameters such as catalyst concentration, reaction time, and reaction temperature were optimized for the production of ackee seed oil biodiesel. The biodiesel yield of 18.30 % was noticed at optimal process parameters. The physicochemical characteristics of the oil such as pour point, cloud point, pH value, specific gravity, viscosity, acid value, saponification value, iodine value,were determined. Gas Chromatograph Mass Spectrometry (GCMS) was also used to determine the elemental composition of the oil extracted. The fuel properties of biodiesel produced were found to be close to that of diesel fuel and also meet the specifications of ASTM standards.Keywords: Transesterification; Ackee seed; Biodiesel; Characterization; Optimal process, Fuel properties.

Abstract: Although fossil fuel continues to play a dominant role in global energy system unfortunately their life span is threatened as the fossil reserves are running out. Except for the fact that they are readily available, tried and tested, unfortunately they bring about a negative environmental and climate impact. When the fossil fuels are burned, they produce both carbon dioxide and carbon monoxide which is the largest driver of global climate change and air pollution. This has caused a need to explore and transition to a cleaner and renewable energy resource like biofuel. Biofuel is a combination of fatty acid alkyl esters achieved by the esterification and transterification of triglycerides that can either be animal fats and vegetable oil with methanol and ethanol. Biodiesel provides several positive benefits by helping in decreasing the country’s dependence on the importation of crude oils, it also reduces the greenhouse gas emissions and advances the lubricating property. Biodiesel is produced and deployed globally with China being the country with the highest biofuel capacity in the world, with nearly 29.8 gigawatts as of 2021. It is followed by Brazil which is ranked second, with a biofuel capacity of 16.3 gigawatts. The selection of a feedstock in biofuel production has a noticeable impact as it determines if a biofuel will be formed or not from the transesterification process performed. The fatty acid / triglyceride content especially the Mono-Unsaturated Fatty Acids (MUFA’s) are of interest. The higher the MUFA’s, the higher possibility of a successful transterification hence biofuel being the by-products/formation with less catalyst and alcohol used. Feedstocks with over 40% fatty acids, especially the MUFA’s are favorable for biodiesel formation. Almost 80% of Macadamia’s fatty acids (MFAs) are palmitoleic acids (C16:1; ~20%) and Monounsaturated, mostly oleic (C18:1; ~60%). This study reviews the preparation of biofuel utilizing Macadamia nut oil (MNO) as a feedstock for sustainable biodiesel Production.

Abstract: Demands for energy are rising as the world's population expands. To meet these demands, fossil fuels have been overused, yet this over reliance on them has led to their depletion. The usage of fossil fuels has also significantly contributed to the release of greenhouse gases, which is a serious environmental concern. Sustainable energy is therefore environmentally friendly and financially sound. Petro-diesel can be replaced by biodiesel because it is biodegradable and less hazardous. Biofuel is any fuel produced from biomass, which can be either animal fats or waste, plant or algae material as a feedstock. Biomass benefits in producing fuels which helps to lessen the demand for petroleum fuel and products. Petroleum fuel and gas increase the greenhouse gas emissions profile of the transportation sector. The Republic of South Africa (RSA) is the 14^th world's largest emitter of greenhouse gases. This is due to the emissions resulting from burning and heavy reliance on coal. Since biofuel can be produced domestically from natural sources like soybeans, rapeseed, macadamia nuts, coconuts, and even leftover cooking, it has the potential to serve as a remarkable substitute for the commonly used petroleum-derived diesel fuel. This study addresses the historical development of macadamia nuts with a focus on the South African Macadamia Nuts (SAMN) industry, its origin, and as a feedstock for biodiesel production. The generation and classification of biodiesel, physicochemical properties, biodiesel standards, and both American Society for Testing and Materials (ASTM), European Committee for Standardization (EN 14214), and South African biodiesel framework standards are discussed. Furthermore, the biodiesel blending requirements, techniques, and benefits were outlined. Finally, the biodiesel regulatory framework of SA and biodiesel framework as per the Biodiesel Task team (BTT) was examined.

Abstract: The Indonesian government is committed to reducing greenhouse gas emissions under the Paris Agreement. One form of this commitment is the program to replace diesel power plants with renewable energy plants in the electricity sector. Fossil-based diesel power plant operations have disadvantages, such as relatively expensive generation costs and greenhouse gas emissions. There are three renewable energy technology options as potential substitutes for diesel power plants: a solar photovoltaic (PV) power plant integrated with a battery energy storage system (BESS), a small-scale geothermal power plant, and a micro-hydropower plant. This paper will analyze the prospects of each technology option based on its economic and environmental impact. Various technical parameters, including renewable energy potential and intermittent factors, as well as economic parameters such as investment and generation costs, are important factors for selecting prospective renewable energy generators. The analysis was carried out by calculating the levelized cost of electricity (LCOE), CO₂ emissions, and oil fuel consumption for four different scenarios. The results of the analysis show that replacing the diesel power plants with micro-hydropower plants can reduce LCOE by 0.24 USD/kWh to 0.12 USD/kWh. The use of a solar PV power plant integrated with a BESS has the most potential to reduce CO₂ emissions, which account for 54% of emissions from diesel power plants. Meanwhile, the potential for oil fuel reduction from this program can reach an annual average of 0.85 million kl.

Abstract: Indonesia has implemented co-firing as a step for renewable energy utilization. Power plants in Northern Java could utilize wood waste from surrounding wood processing industries as co-firing fuel. In this study, wood waste with high value of ash fusion and stock coals of power plant were used as samples. Blended coals from stock coals are selected based on calorific value, slagging-fouling-abrasion prediction, and softening temperature prediction. Selected blended coals are mixed with wood waste in percentage of 10 wt% to 90 wt% to produce co-firing fuel which then predicted for risk tendency of slagging-fouling-abrasion by theoretical indices. The result shows that the addition of wood biomass increases the slagging, fouling, and abrasion tendency. In this study, addition of 20-30 wt% wood waste to blended coals can still be recommended with the medium risk of slagging-fouling and low risk of abrasion tendency.