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The pyrolysis of palm shell was performed in a batch conical spouted bed to examine the effects of pyrolysis temperature and time, particle size, and static bed height on the product yields and properties. The optimal pyrolysis condition derived from the batch operation, which produced maximum liquid product yield, was selected for the pyrolysis tests in a continuous mode from which only the effect of pyrolysis temperature was studied. It was found that pyrolysis temperature and time showed a strong effect on the pyrolysis product yields, while particle size and static bed height showed almost no significant effect. For the continuous spouted bed operation, the maximum liquid yield of 65 wt% was obtained under the test condition. With regard to the pyrolysis products, the bio–oil obtained is probably less attractive to use as a direct fuel, due to its high water content, low calorific value and high acidity. The derived solid product gave a calorific value of 31 MJ/kg and a BET surface area of 200-220 m²/g. Carbon monoxide and carbon dioxide were the dominant components in the gas product. Batch and continuous operations yielded similar char properties and gas compositions. [ABSTRACT FROM AUTHOR]

Effect of KOH, reaction temperature and time, and introduced carbonization step on the amount and composition of syngas as well as porous properties of the carbon products for CO2 gasification of coconut shell at low temperatures (300–700°C) was investigated. Results showed that the presence of potassium hydroxide and gasification temperature had a significant effect on the amount and composition of syngas product and facilitated the rate of hydrogen and carbon monoxide formation. It was also found that carbonization step could promote the generation of hydrogen gas as well as increasing the gas heating value per kg of gas. Furthermore, the porosity development of carbon product was found to be influenced by the chemical ratio and gasification temperature. The optimal conditions for achieving high hydrogen composition and specific surface area were to gasify coconut shell under CO2 at 600°C for 60 min with carbonization step and with chemical weight ratio of 3.0. This condition gave the hydrogen composition as high as 29.70 %weight of produced syngas with heating value of 41.4 MJ/kg of gas and specific surface area of 2650 m2/g of the carbon product. [ABSTRACT FROM AUTHOR]