Papers by Keyword: Carbon

Abstract: This study investigates the effects of fiber type and hybridization on the tensile properties of epoxy composites produced using the temperature-controlled vacuum-assisted resin transfer molding (VARTIM) method. Tensile strengths and fracture behaviors are examined by fabricating 6-layer glass fiber-reinforced composites [G6], 6-layers carbon fiber-reinforced composites [C6], and hybrid composites consisting of six layers of glass and carbon fibers [H1] and [H2]. The microstructures of the composites are analyzed using an optical microscope, and tensile tests are conducted in accordance with ASTM standards. Tensile tests are performed at a constant speed and room temperature, and the fracture surfaces after tensile testing are analyzed using a Stereo Microscope. The results showed that the highest tensile strength is achieved in the carbon fiber-reinforced composite (CFRP), with an increase of approximately 123% compare to the glass fiber-reinforced composite (GFRP). Hybrid composite exhibits the reduced tensile strength compare to CFRP, with decreases of 23% for H2 and 29% for H1, respectively, whereas, increased the fracture toughness of the tested samples. Additionally, fracture surface analysis reveals that GFRP exhibits incomplete separation of the fractured surfaces, while CFRP shows a brittle and clean fracture surface. This study highlights the significant impact of fiber type and hybridization on the tensile property and fracture behavior of epoxy composite, demonstrating the better tensile performance of CFRP, while improving the fracture toughness and manufacturing cost of both GFRP and Hybrid composite.

Abstract: The construction industry remains a major contributor to global CO₂ emissions, primarily due to its high consumption of non-renewable mineral resources and energy-intensive materials. In response to the growing need for sustainable alternatives, this study focuses on valorizing lignocellulosic biomass waste specifically Solid Olive Waste (SOW), a byproduct of olive oil production abundant in Mediterranean countries as a partial replacement for mineral aggregates in concrete. The main objective is to develop and evaluate an Innovative Solid Olive Waste Composite (ISOWC) as an eco-friendly material suitable for construction sector. The incorporation of SOW was optimized using the Talbot–Fuller–Thompson (T-F-T) semi-empirical method, which enabled the determination of ideal incorporation rates (10%, 20%, and 30% by aggregate volume) based on maximum packing density. Composite formulations were developed using the volumetric mix design method, incorporating both raw and water-saturated SOW. Comparative tests demonstrated that saturated SOW significantly improved the composite’s compressive strength and thermal conductivity, particularly as the SOW content increased. To further assess performance, a sensitivity analysis was conducted on ISOWC with 30% saturated SOW at varying cement dosages (200–350 kg/m³). The formulation with 200 kg/m³ cement achieved a compressive strength of approximately 6 MPa and thermal conductivity of 0.72 W/mK, meeting the criteria for insulating applications such as blocks and cladding panels. These results highlight the promising potential of ISOWC and support further investigation into the use of Solid Olive Waste as a full replacement for gravel in the development of eco-efficient, sand-based concretes.

Abstract: This investigation was carried out in a lab setting with the aid of a filter set. This study aimed to lower the level of clean water contamination and assess the filter media's performance in Fitu Village, Ternate City, using physical and chemical criteria. Temperature, turbidity, total dissolved solids (TDS), and odour are physical parameters. While pH, Mn (manganese), and Fe (iron) are the chemical parameters. Sand-activated carbon made of silica and zeolite is the filter medium. One hundred eighty litres of water from a resident's well make up the sample. The physical characteristics, namely the TDS of 1250 mg/L, the turbidity of 27 NTU, and the temperature of 25 °C, show the outcomes of investigating healthy water as raw water in the Kelurahan Fitu. Fe concentration was 1.3 mg/L, Mn concentration was 0.6 mg/L, and pH was 9. Water is passed via silica sand, zeolite, and activated carbon filters before entering the filter after further inspection. According to the results, the TDS has dropped to 897 mg/L, the turbidity has changed to 24, and the temperature is 24 °C. The filtered water meets the chemical standards for Fe concentration with only 0.91 mg/L of Fe, 0.45 mg/L of Mn, and a pH of 7.9. According to the study's findings, inhabitants of Fitu Village in Ternate City can efficiently reduce pollutants and metal levels in their healthy water by employing a filtering system that uses silica sand filter media, zeolite, and activated carbon.

Abstract: Due to its abundant availability and classification as biomass, the focus in renewable energy is currently centred on the use of Oil Palm Empty Fruit Bunches (OPEFB) as an alternative material for carbon production that can be used in many applications, one of which is batteries. The type of battery that is trying to use is a primary battery. The purpose of this study is to determine the effect of different concentrations of NaOH activation and immersion time on OPEFB activated carbon by analyzing the result of surface area, morphology, and electrical properties. The study found that 1 M NaOH concentration and an 18-hour immersion time were optimal, producing a surface area of 281.96 m²/g and a voltage of 0.785 V. These findings align with and contribute to existing research on biomass utilization in energy storage, demonstrating the potential of OPEFB-activated carbon in battery applications and highlighting the significance of further research in this area to enhance battery performance and scalability.

Abstract: The article provides information about the initial elements in the waste and tailings of the copper processing plant of the Almalyk Mining and Metallurgical Combine and theoretical solutions for the extraction of metals. According to chemical data, the amount of iron in the waste is high (52.6%), and the most effective solution for extracting iron from the waste is the reduction process. An increase in the amount of iron to 88.9% was formed using coal and lime as reducing agents.

Abstract: Disposing of dyes without proper treatment can cause water pollution because disposable dyes have a complex composition and are inert, so they must be adequately treated before being discharged into the waters. Using carbon from sugar palm (Arenga pinnata) fiber waste modified with iron oxide can be an alternative functional adsorbent for dye waste. The production of this practical adsorbent starts with carbonation of palm sugar fiber, chemical activation using H₂SO_4, incipient wetness impregnation with Fe(NO₃)₃.9H₂O and ends with calcination at various temperatures of 200 °C, 300 °C; and 400 °C for 2 hours. The resulting carbon adsorbent material is characterized using FTIR (Fourier Transform Infrared), XRD (X-Ray Diffraction), and SEM (Structural Equation Modeling) analysis. In addition, the absorption capacity of the adsorbent for the dye waste is tested using the UV-VIS (Ultraviolet-Visible) instruments.

Abstract: There is a growing demand for sustainable alternatives to petroleum based fuels to be used in the preparation of activated carbon for energy and manufacturing sector. Rice husk (RH) is widely available in rice producing countries and found to be good source for activated carbon. The present study proposes the optimization and characterization of activated carbon from rice husk in a single step using response surface methodology with the full factorial design. In this study, rice husk was carbonized at fixed temperature and activated at different temperatures (700–900°C) and residence times (60–90 min). The optimum condition for recovery, iodine value and surface area was achieved at 900°C and 60 min residence time with desirability being 65%. The recovery, iodine value and surface area at optimum conditions were 19.80%, 865.77 mg/g, and 589.67m²/g, respectively. Overall, the carbonization and activation in a single step resulted god quality of activated carbon for variety of applications.

Abstract: Graphenic carbon (GC) has been successfully synthesized from biomass (coconut shell charcoal) using the liquid phase exfoliation method. The dopants, in the form of light atoms such as boron (B-GC), were introduced with the aim of improving their magnetic properties. X-ray diffraction was used to identify the GC and B-GC, and the results show broad peaks around 24° and 43°, indicating the presence of graphene-like carbon structure. The bonding structure was also analyzed using X-ray photoelectron (XPS). It reveals the main bonds in GC consist of sp², sp³, and C=O. While the B-GC sample shows an additional bond, namely the B-C bond, as an indicator of the successful doping process of B into the GC structure. Both GC and B-GC show weak room temperature ferromagnetism. Furthermore, these findings show that introducing boron atoms into the graphenic structure can improve magnetization.

Abstract: Muon-spin relaxation (μSR) spectroscopy has let an understanding of the hydrogen interactions with graphene, providing insights for hydrogen storage technologies based on graphene-based compounds. We report an μSR study on the reduced graphene oxide (rGO, a product of ®Graphenea) at 300 K. Spontaneous muon-spin precession is not observed under the high statistic zero-field measurement. Instead, the spectra show a typical muon diffusion with a small fraction of muon experiencing dipolar interactions with neighboring protons. Measurements under longitudinal field conditions yield the obtained hyperfine field (B_hyp) a way much lower than the required field to recover free muonium, demonstrating a radical formation. Moreover, a noticable ratio of captured muoniums (~35%) in the sample illustrates strong interactions between hydrogen and rGO.

Abstract: Different types of fabrics, such as aramid, carbon, basalt, glass, and flax, as well as powder fillers, were used to manufacture the epoxy-based hybrid composites by the vacuum bagging method. In this work, the resistance of hybrid composites was examined in terms of their resistance to acts of vandalism, such as resistance to cuts with sharp objects, impacts, and flames. These technics were applied to determine the impact of the type of fillers and fabrics on the performance of hybrid composites.