Key Engineering Materials Vol. 908

Abstract: Combination of high energy radiation and chemical vapour deposition in the grafting process for the synthesis of metal adsorbent was investigated. Radiation-induced grafting of glycidyl methacrylate onto kenaf fiber was performed in vapour phase to develop adsorbent for removal of aluminum from aqueous solution. Morphological changes of cross-section kenaf fiber was observed via scanning electron microscope and the thickness of co-monomer in the final graft co-polymer was determined. The comparison in cross-section morphology between ungrafted kenaf fibers and grafted kenaf fiber shows approximately 3.88 [μm] thick of additional grafted layer. The functionalization of the grafted fiber using imidazole was calculated grametrically and verified by elemental analysis. Imidazole has proven to be effective on the adsorption of aluminum ion. It was found that the adsorbent could remove more than 99% aluminum with the highest adsorption capacity of 4.93 [mg/g] at pH 4 and 60 minutes reaction time.

Abstract: The present study was conducted to investigate the properties of fabricated polythersulfone ultrafiltration membrane by incorporating ionic liquid (IL) (Aliquat 336) in the casting solution towards HA removal. IL namely Aliquat 336 is used with varied composition of polyethersulfone (PES) as polymer and and Dimethyl acetamide (DMAC) as a solvent. All the fabricated membranes were characterized by Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), ganiometer and Thermogravimetric analysis (TGA) analysis. The fabricated membranes were also analyzed through its performance based on water flux, HA flux and HA rejection. The experimental results show that the incorporation of ionic liquid in different composition of polymer resulted in different characteristic of membrane and provided in improvement of HA removal. The P4 membrane gave the best performance with the water flux of 373.25 L/m².h, the HA flux of 262.68 L/m².h and the highest removal of HA up to 90%.

Abstract: Titanium dioxide (TiO₂) has been acknowledged as a promising photocatalyst in environmental remediation including wastewater treatment. In this study, TiO₂ nanoparticles co-doped with iron (Fe) and nitrogen (N) was synthesized via sol-gel method and subsequently followed by calcination process at 300 °C, 500 °C and 700 °C for 3 hours. The prime objective of this study is to investigate an effect of different calcination temperatures in enhancing the photocatalytic activity of synthesized TiO2 which was evaluated through the degradation of methyl orange (MO) dye. The structure and properties of the prepared samples were studied by X-Ray Diffraction (XRD), Energy Dispersive X-Ray Spectroscopy (EDX), Field Emission-Scanning Electron Microscope (FE-SEM) and Ultraviolet-Visible Spectrophotometer (UV-Vis). The results obtained from XRD showed the presence of anatase phase in all samples at 300 °C and 500 °C. Further increase of calcination temperature up to 700 °C, mixed-phase of anatase and rutile formed. XRD results also suggest that the addition of impurities has a great effect on the crystallinity and particle size of TiO₂. The obvious agglomeration phenomena existed in the annealed samples with nanometer size, as observed in FESEM images. The photocatalytic performance under UV light shows that co-doped Fe, N-TiO2 at 500 °C indicated highest MO degraded of 96.5 % within 3 hours of irradiation time. From the current finding, Fe,N-TiO₂ possessed the potential to be commercialized as a photocatalyst in wastewater remediation especially in treating dye pollution.

Abstract: This paper highlights a study on the effects of medium dose gamma (γ) irradiation towards physical properties of TiO₂ nanoparticles. Doses applied for gamma irradiation are 60, 100 and 150 kGy. Structural and morphological results show that gamma radiation did not change the crystallinity and shapes of TiO₂ nanostructures. Ratio percentages of anatase:rutile for irradiated samples is around 89:11. Agglomerated samples shown in morphology images is support with the existence of binodial shapes peak from particles size distribution analysis.

Abstract: FeCoNiAlSi and FeCoNiAlBSi high entropy alloys (HEAs) were synthesized by mechanical alloying. Phase evolution, crystallite size, lattice strain, microstructure and morphology for the two alloys were investigated. It was found that two simple structures which are face-centred cubic (FCC) and body-centered cubic (BCC/B2) solid solution appear in FeCoNiAlSi HEA after 50 h of milling. Formation of Fe₂B peak was observed in the XRD pattern when a small amount of boron was added to the base alloys. The particle size of the alloy was increased after 20 h of milling time. The structural analysis shows that the average crystallite size decreases while lattice grain size increases with the increasing milling time. The morphology structure of the milled powders shows the particles size becomes rounded, flat and rough as the milling time prolongs. The newly developed HEA synthesized by mechanical alloying is expected to provide prominent efficiency in degradation of azo dyes (Methyl Orange). Although the HEAs have been reported to provide larger surface area and excellent capacity, only a few studies have been reported on degradation of azo dye by using HEAs as catalyst. Therefore, the method derived from the results of this study will contribute in treating azo dyes for wastewater treatment. Keywords: azo dye; high entropy alloys; mechanical alloying; crystal structure; morphology

Abstract: The existence of naphthenic acid (NA) in acidic crude oil tends to corrode the oil refinery equipment. In this study, a catalytic deacidification reaction involving the deacidifying agent and the synthesised catalyst was aimed to eliminate NA from acidic crude oil. Diethanolamine-polyethylene glycol (DEA-PEG) was introduced as a deacidifying agent. The wet impregnation method was applied for synthesizing the calcium oxide catalyst doped by copper supported on alumina (Cu/Ca/Al₂O₃). The potential catalyst was characterised utilising field emission scanning electron microscopy-energy dispersive X-ray (FESEM-EDX), Brunauer-Emmett-Teller (BET), and X-ray diffraction spectroscopy (XRD). The parameters include deacidifying agent dosing, loading dopant ratio and catalyst calcination temperature were performed to enhance the catalytic deacidification process in this study. Data showed that the total acidic number (TAN) value for crude B met the PETRONAS requirement for the TAN value below one using 1500 mg/L of DEA-PEG assisted by Cu/Ca (10:90)/Al₂O₃ catalyst.

Abstract: The production of fermentable sugar from sugarcane bagasse acid hydrolysis method was investigated in this study. Experimentation on the determination of acid for hydrolysis was carried out to identify the suitable type of acid for the effective hydrolysis process. The results revealed that sulphuric acid (H₂SO₄) is a better hydrolysing agent than phosphoric acid (H₃PO₄). This study also analysed the impact of temperature, on the yield of fermentable sugar between the sugarcane bagasse. The highest amount of fermentable sugar of 10.26 g/L was produced by sugarcane bagasse at temperature of 90°C, acid concentration of 4% (w/v) and a reaction time of 3 hours.

Abstract: Deforestation issues increased dramatically every year specially to produce paper. Therefore, to supplement the limited wood fibre resources, non-wood fibres especially sugarcane bagasse introduced an alternatives resolve for raw material is considered in paper-based industries. This study addresses the analysis of magnetic sugarcane bagasse materials as substitute fibres in papermaking. Paper is generally made with cellulose fibre which has some specific features used for educational, packaging, and cleaning purposes. Sugarcane bagasse (Saccarhum officinarum) is popular for its cellulose, holocellulose, and lignin that far more convenient than wood fibres. Meanwhile, the demands of magnetic material in magnetic papermaking industry has increased due to its excellent mechanical characteristics. As the magnetic paper shows some superiority in properties such as renewable use and folding resistance. The used of filler in this study is to alter the properties such as texture, opacity, brightness, dimensional stability, and overall printability. Thus, the used of ferrite (Fe) magnet as a filler can enhance the paper properties. Ferrite is recognized as a hard-magnetic material with distinct properties such as good mechanical hardness and chemical stability, therefore it is a much more convenient material for magnetic paper production. Through the observation under Scanning Electron Microscope (SEM), the image obtained shows that magnetics sugarcane bagasse paper was more convenient to be used as an alternative for paper making. Next, Fourier-Transform Infrared Spectroscopy (FTIR) recognizes the presence of a functional group of the magnetics sugarcane bagasse paper. Moreover, the chemical properties obtained from this study show that the magnetics sugarcane bagasse was as good as the commercial paper available in the industries. To increase the integrity of the paper, the radiation process by using gamma-ray was done to the paper to see the different for pre and post radiation.

Abstract: Bamboo saw dust (BSD) as reducing agent in low-grade manganese ore leaching is used, and therefore the performance of cellulose hydrolysis will affect the percent recovery of Mn ore. This work is studies the effect of sulphuric acid and speed rotation on hydrolysis of BSD. The crytallinity of BSD were investigated. The parameters considered in this work are sulphuric acid concentration and the speed rotation by using 2³ +3 factorial design. The significant factor, main and interaction effect were investigated based on Analysis of Variance obtained from statistical software. It shows that the sulphuric acid concentration is the main factors that affects the percentercent crystallinity compared to rotation speed. It is proved by the DOE analysis and supported by the crystallinity analysis of BSD before and after hydrolysis process. The optimum condition that can be suggested to obtain low percent crystallinity are when the sulphuric acid concentration and speed rotation at 4M and 400 rpm respectively. This indicates that reducing agent can be obtained from BSD in mild condition of hydrolysis due to decrement of cellulose crystallinity

Abstract: The AlCrFeNi alloys has successfully synthesized with the composition of Al, Cr, Fe, and Ni at 25 atomic percent. The synthesis of this material is to obtain an alloy intended as nuclear fuel cladding for a research reactor with high uranium density. The AlCrFeNi alloys made from pressed powder then sintered at temperatures of 800, 900, and 1000 °C with a dwelling time for one hour. Sintering process was conducted in inert atmosphere. The obtained alloys were analyzed using the X-ray diffraction (XRD) for phase analysis and the Scanning Electron Microscope (SEM) for morphological observation and elemental analysis. From the diffraction pattern, the three alloys synthesized had the dominant B2 phase. Alloys sintered at 800 °C and 900 °C show the FCC phase linear in composition value with the sintering temperature. From the diffraction pattern, a theoretical density value is also obtained. The results indicate that the alloy with the only B2 phase has the lowest density of 5.932 g/cm³. From the SEM micrographs, it can be seen that the morphology of the alloys have relatively large cracks. The elemental analysis results to confirm the alloy's phase composition obtained a ratio of Al and Ni, which only allows the B2+FCC phases to form.