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This paper presents an alternative utilisation of sago barks from the sago industry. In this study, a sago bark-derived magnetic adsorbent was developed by impregnation with ferric chloride hexahydrate (FeCl3H2O) and carbonisation method. The potential of the sago bark-derived magnetic adsorbent to remove lead ion (Pb2+) and copper ion (Cu2+) from aqueous solution was assessed in a batch system. Adsorption experiments were performed as a function of initial concentration (5.0 – 15.0 mg/L). The magnetic adsorbent displayed good ferromagnetic property which aids the separation of the adsorbent after the decontamination process. The magnetic adsorbent was characterised by Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy embedded with an Energy Dispersive X-ray Spectrometer (SEM-EDX). The FT-IR spectra analysis revealed the surface functional groups of the magnetic adsorbent are C−O−C, C−OH, C− H, −C−C−O, Fe-O, O-H, and C-O. The maximum monolayer adsorption capacities were discovered to be 172.414 and 12500 mg/g for lead and copper ions, respectively. The batch adsorption isotherms were analysed using Langmuir, Freundlich, Jovanovic and Temkin isotherm models. The experimental data perfectly fitted with Langmuir isotherm modelling. The results indicated that the sago bark-derived magnetic adsorbent potentially to be an alternative in replacing more high-priced adsorbents for its application in heavy metal ions removal.

Thermal accumulation in a car cabin under direct exposure to sunlight can be extremely critical due to the risk of heatstroke especially to children who are left unattended in the car. There are very limited studies in the literature to understand the thermal behaviour of a car that is parked in an open car park space and the findings are mostly inconsistent among researchers. In this paper, the studies of thermal accumulation in an enclosed vehicle by experimental and computational fluid dynamics simulation approaches were carried out. An effective and economical method to reduce the heat accumulation was proposed. Different test conditions such as fully enclosed, fully enclosed with sunshade on front windshield and different combinations of window gap sizes were experimented and presented. Eight points of measurement were recorded at different locations in the car cabin and the results were used as the boundary conditions for the three-dimensional computational fluid dynamics simulation. The computational fluid dynamics software used was ANSYS FLUENT 16.0. The results showed that the application of sunshade helped to reduce thermal accumulation at car cabin by 11.5%. The optimum combination of windows gap size was found to be with 4-cm gap on all four windows which contributed to a 21.1% reduction in car cabin temperature. The results obtained from the simulations were comparable and in agreement with the experimental tests.

Absorption process is the most common method that is being applied to sweeten sour gas in the oil and gas industry. However, this process does have several consequences which will trigger the foam formation of foam that will reduce the mass transfer efficiency and absorption capacity as well as amine solutions carryover to the downstream processes. The removal of undesired contaminants in activated methyldiethanolamine (MDEA) was conducted by utilizing magnetic activated carbon (MAC). In this work, MAC was synthesized from coconut husk through chemical activation and co-precipitation methods. The performance of this material as an adsorbent was evaluated based on the foaming behaviour of activated MDEA solvent after being contacted with MAC at different duration and varying amounts. Nitrogen gas was introduced into the solvent through a gas diffuser to create foam. Based on the results, the foam volume generated by activated MDEA solvent was identified to decrease with the increase in both MAC contact time and amount. The highest removal efficiency by MAC was identified to be at 1hour contact time between MAC and activated MDEA solvent where the foam breaking time was reduced to 10-30minutes. Meanwhile, the addition of 50% MAC into the solvent was able to further decrease the foam breaking time to 5-10minutes. The characteristics of the prepared MAC were evaluated through various instrumental analyses. This study shows that the MAC synthesized from coconut husk has a good potential as an adsorbent in removing the contaminants in activated MDEA solvent to reduce foam formation.

The objective of this study was to develop a simple and cost-effective method to produce biofertilizer using agro-wastes. There were five types of agro-wastes being used in this study. They were wastes from watermelon, papaya, pineapple, citrus orange, and banana. Solid-state fermentation method was used to produce biofertilizer, which was then applied into vegetable plantation. Physical property tests were done on the plant samples of 5 weeks of age in order to determine the effectiveness of the biofertilizer. The results of the experiment showed that the plant samples treated with biofertilizer from watermelon, papaya, and banana wastes had promising physical characteristics. Other tests such as analyses of pH values and potassium content in the biofertilizers were also done in this research. It was found that watermelon biofertilizer had the highest pH value (5.15). The banana biofertilizer had the highest content of potassium with a content of 3.932 g K/L.