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The purpose of the current study is to identify the potential of energy-efficient hydrogen (H2) production from date seeds as biomass via steam gasification process along with heat integration in Gulf countries. A reaction kinetics model has been established for steam gasification with in-situ carbon dioxide (CO2) capture of date seeds using MATLAB software. The kinetics of reactions involved in the gasification process was calculated using the optimization parameters fitting approach. The heat integration model has been developed via mixed integer nonlinear programming (MINLP) in MATLAB. In the parametric study, temperature and steam/biomass ratio considered their impact on syngas composition and energy recovery. Results showed that both variables have a strong positive effect on H2 production and depicted maximum production of 68 mol% at a temperature of 750 °C with steam/biomass ratio of 1.2. Methane (CH4) and CO2 production were low in the product gas, which showed the activity of water gas shift reaction, methanation reaction, and carbonation reaction. Utilization of waste heat via process heat integration within the system reduced system's external heat load. More than 70% of energy recovered, which could be utilized for gasification and steam production. Energy analysis and process heat integration proved a prospective approach for energy-efficient and sustainable hydrogen production from date seeds.

Activated carbon (AC) derived from gasified Glyricidia sepium woodchip (GGSWAC) were prepared using KOH and CO2 activation via microwave radiation technique to remove atenolol (ATN) from aqueous solution. The surface area (SBET) and total pore volume (TPV) of GGSWAC were 483.07 m2/g and 0.255 cm3, respectively. The n-BET model fits well with the isothermal data indicating a multilayer adsorption with the saturation capacity of 121, 143 and 163 mg/g at 30, 45 and 60⁰C, respectively. The kinetic study showed that ATN adsorption followed Avrami model equation (R2≅0.99). Based on the thermodynamic parameters, the adsorption of ATN onto GGSWAC was endothermic (ΔHS = 234.17 kJ/mol) in the first layer of adsorption and exothermic in the subsequent layer (ΔHL = -165.62 kJ/mol). The ATN adsorption was controlled by both diffusion and chemisorption. In continuous operation, the Thomas (R2= 0.9822) and Yoon–Nelson (R2= 0.9817) models successfully predicted the ATN adsorption.

The abundance of gasification char residues which contributed to solid waste management problem is one of the major concerns in biomass gasification industry. This study focuses on synthesizing gasified Glyricidia sepium woodchip based activated carbon (GGSWAC) for the removal of basic green 4 (BG4) dye, evaluating the GGSWAC physicochemical properties and assessing the BG4 adsorption performance in batch and fixed-bed column systems. The optimal conditions of GGSWAC synthesis were at radiation power, time, and impregnation ratio (IR) of 616 W, 1 min and 1.93 g/g, respectively. The surface area (SBET) and total pore volume (TPV) of GGSWAC were 633.30 m2/g and 0.34 cm3/g, respectively. The Fritz–Schlunder best fitted to the experimental data at all temperatures in the isothermal studies, indicating a monolayer adsorption. The kinetic study showed that BG4 adsorption followed Avrami kinetic model. Based on thermodynamic parameters, the adsorption of BG4 dye onto GGSWAC was an endothermic and spontaneous process. In continuous operation, the Thomas and Yoon–Nelson models successfully predicted BG4 adsorption onto GGSWAC. The low production cost of 0.54 USD/kg showed that GGSWAC is economically feasible for commercialization.

This study presents the preparation of rubber seed coat based activated carbon (RSCAC) via microwave irradiation assisted KOH activation for adsorption of malachite green (MG) in aqueous solution. The effects of MG initial concentration (100-500 mg/L), contact time (0-24 h) and solution temperature (30-60 °C) were evaluated through batch adsorption test. The MG dye uptake increased with increased in initial dye concentration and contact time. The equilibrium data were favorably described by Freundlich isotherm, while adsorption kinetic was best fitted to the Lagergren model. The adsorption rate of process was endothermic and controlled by film diffusion. The findings support the feasibility of rubber seed coat as an attractive precursor for dye removal.

Pyrolysis of rice straw using microwave irradiation with quartz glass reactor has been conducted in a 1 kW domestic microwave system having 2450 MHz frequency. The microwave was modified and was equipped with the cylindrical quartz glass reactor. There are three process parameter studied namely microwave power (watt), the amount of microwave absorber (g), and particle size (μm). The microwave absorber used in this study is char which produced from microwave assisted pyrolysis. From the study, it was found that the addition of microwave absorber had significant effects on the yields and properties of the final products. From the work done, 12.97 % of bio-oil yield was the highest amount of bio-oil produced at microwave power of 500 W, with addition of 0.5 g of microwave absorber (bio char) for the particle size of 125 μm with consistent flow of 5 L/min of nitrogen gas and constant of 10 minutes reaction time. The pH analysis of bio oil was done by using pH meter for randomly selected one reading for each parameter study where the pH of bio oil produced is acidic which is 3.11, 3.18 and 3.86. The bio-oil produced was found to contain important chemical compounds such as cyclohexanol, 2,3-dihydro-1-benzofuran, 2-methoxy-4-vinylphenol and 4-ethylphenol which analyzed by using gas chromatography.

Rice husk is one of the major agriculture waste that has high potential as carbon and energy source and does not been utilized well. The potential was in producing bio oil and pyrolysis is one method that has been established for the purpose. In this research, the pyrolysis of rice husk by using microwave irradiation as the heating source in the existence of microwave absorber char was investigated. The effect of three operating variables, namely microwave power (Watt), reaction time (min) and the amount of microwave absorber (g) were studied. From the study, The highest bio-oil yield were produced about 40.75% at microwave power of 600 W, 20 min reaction time, and 3.5 g amount of microwave absorber with consistent flow of 4 L/min of nitrogen gas. The bio-oil produced were analyzed using gas chromatography and was found contains important chemical compounds such as phenols, ketone, aldehyde and carboxylic acids.

The aim of this study was to optimize the monoepoxidation process of linoleic acid obtained from Malaysian Jatropha curcas oil using central composite design (CCD). There were four independent variable factors had been studied which involved reaction temperature (X1), reaction time (X2), catalyst loading (X3) and H2O2 concentration (X4). Thirty experiments were carried out based on the experimental design responses obtained. The results showed that the optimum condition was obtained at catalyst loading of 0.11% (w/w) methyltrioxorhernium (VII) (MTO), H2O2 mole of 99%, reaction temperature of 58.41oC for 5 hours. The central composite design was proven to be simpler method, time saving and required less samples compared to the conventional method.

Standing for long periods of time has been recognized as a potential contributor to muscle fatigue. When a person is performing activities in prolonged standing and wearing ineffective material of shoe insole, not only lead to muscle fatigue but can even cause injuries in the long term. The objective of this study is to determine the effects of two types of shoe insole materials; Ethylene Vinyl Acetate (EVA) and a combination of polyurethane (PU) and poron on muscle activity and foot pressure. The analysis of muscle fatigue was performed using surface electromyography (sEMG) while pressure under the foot was measured using FScan device. Results of comparison found that the two types of shoe insole materials showed significant difference (p-value < 0.05) in electromyography signals (µV) in the left and right gastrocnemius muscle while there are significant reductions on the peak pressure measured from the foot pressure measurement. It can be concluded that the combination of PU and poron is an effective material to be used a shoe insole for a person who is exposed to prolonged periods of standing.