Zaidi Ab Ghani

Pyrolysis of Jatropha curcas L. husk: Optimization solid, liquid and gas yield by using response surface methodology (RSM)

This study aimed to develop an optimal condition for production of solid and liquidproducts from the pyrolysis of Jatropha curcas L. husk. Response surface methodology (RSM) based on central composite rotatable design (CCRD) was applied to optimize the combination effect of three important reaction variables, i.e. reaction temperature (°C), heating rate (°C/min) and nitrogen gas flow rate (ml/min). The reaction was performed via vertical fixed-bed reactor. A total of 20 individual experiments were conducted. The results showed that the RSM based on CCRD is well adaptable for pyrolysis studied in this system. The predicted optimum conditions for production of solid and liquid yield from the pyrolysis of Jatropha curcas L. husk was at 400°C reaction temperature, 60 °C/min heating rate and 120 ml/min nitrogen gas flow rate with char, liquid and gas yield at 38 %, 28.9 % and 33.0% respectively.

Penyediaan secara optimum arang teraktif daripada sisa tanaman cendawan terpakai (SMFW) melalui reka bentuk box-behnken dari kaedah gerak balas permukaan

This study focuses on activated carbon preparation from spent mushroom farming waste (SMFW) via chemical activation using Box-Behnken design (BBD) of Response Surface Methodology (RSM). Potassium hydroxide (KOH) functions as activating reagent and it plays an important role in enhancing the activated carbon porosity. Three input parameters and two responses were evaluated via this software generated experimental design. The effects of three preparation parameters of impregnation ratio, activation time and activation temperature as well as two responses of carbon yield and iodine number were investigated. The optimum conditions for preparing activated carbon from SMFW was found at SMFW: KOH impregnation ratio of 0.25, activation time of 30 min and activation temperature of 400 C which resulted in 28.23 % of carbon yield and 314.14 mg/g of iodine number with desirability of 0.994. The predicted results were well corresponded with experimental results. This study is important in economical large scale SMFW activated carbon preparation for application study of adsorption process for metal treatment in wastewater with minimum chemical and energy input.

Co-liquefaction of low rank Malaysian coal and Palm Kernel Shell — The effect of temperature

The co-liquefaction of Mukah Balingian (MB) Malaysian coal with the Palm Kernel Shell (PKS) was studied to investigate the synergistic effect by comparing the conversion and product yields. Co-liquefaction results thus far indicate there exists an obvious synergestic effect between MB and PKS, which is depends on liquefaction temperature. Thus far, the results showed that the conversion and oil + gas yields were comparatively much higher than the liquefaction of the MB coal alone. The largest synergistic effect is obtained at low temperature of 400 °C and then decreases as temperature increase. The liquefaction conversion of 88.6 % and oil+gas of 77.6 % of the co-liquefaction at this optimal temperature are higher than that of corresponding values from the invidual liquefaction of MB coal.

Coal liquefaction using semi-continuous solvent flow two-stage reactor system: Optimizing using response surface methodology (RSM)

Response surface methodology (RSM) was applied to optimize the condition for liquefaction process of Mukah Balingian (MB) low-rank Malaysian coal by using semi-continuous solvent flow two-stage reactor system. The reaction was performed by using tetralin as the solvent. A central composite rotatable design (CCRD) was employed to optimize the effect of three important reaction variables, i.e. flow-rate (ml/min), reaction time (min) and Ni loading (wt.%). A total of 20 experiments were conducted. It was concluded that the liquefaction should be carried out under solvent flow-rate of 1.12 ml/min, reaction time of 60 min and 5 wt.% of NiSiO2 loading. Under the optimum conditions, the corresponding response value for oil+gas yield was 71.25 %.

Thermogravimetric analysis of Silantek coal, Palm Kernel Shell, Palm Kernel Shell char and their blends during combustion

Preliminary thermogravimetric studies of Silantek coal (SL), Palm Kernel Shell (PKS), PKS char and their blends have been performed in a Thermogravimetry Analyser(TGA). PKS char were produced using microwave irradiation carbonization system at power of 300 Watt, with nitrogen flow rate of 150 mL/min for 30 minutes. Combustion tests of raw and blends samples were carried out in purified air atmosphere conditions at heating rates of 20 °C/min. The SL/ PKS and SL/ PKS char blends were prepared in the weight ratios of 80:20, 60:40, 50:50, 40:60 and 20:80. Derivative thermogravimetric (DTG) results which represent the decomposition of volatile matters and char showed that raw PKS has higher reactivity than SL during combustion process. The thermal profiles of the SL: PKS blends correlated with the percentage of PKS added in the blends, representing lack of synergic effect between both samples. SL and PKS char blends results in single evolution peak, indicated possibility to be used as alternative fuel for combustion. These findings may be useful for the power generation industry in the development of future co-firing plants using coal/ biomass; however, significant development work is required before large-scale implementation can be done.