Oil can be recovered from kerogen in oil shale by pyrolysis. The devolatilization kinetics of the pyrolysis of oil shale from the Irati Formation in Brazil was studied. Kinetic parameters were determined from dynamic thermogravimetric analysis over the temperature range 323–1173 K, using different model-free methods. Evaluation and validation were performed by pyrolysis at 673 K for 3 hours. It was found that the activation energy depended on the extent of conversion. Activation energy increased over the range 215–255 kJ/mol for conversion in the range 0.15 ≤ α ≤ 0.55, where α = 1 for pyrolysis at 1173 K. When the reaction rate was high, the conversion calculated using kinetic parameters derived by the Friedman method was more accurate than those calculated from the Flynn–Wall–Ozawa and the Kissinger–Akahira–Sunose methods. The latter two methods performed better when the reaction rate was lower, i.e., at higher conversion. Isothermal kerogen pyrolysis approached an incomplete conversion limit that could be increased only by increasing the temperature; this type of behavior was predicted by the conversion dependence of activation energy. The observed activation energy is an average of the different activation energies of the individual compounds in kerogen. As conversion progresses, the compounds with lower activation energies are more readily converted, so that the average activation energy of the compounds that remain increases with increasing conversion. The work highlighted the importance of employing conversion-dependent kinetic parameters when modeling oil shale pyrolysis for process design, especially when the process is designed for high kerogen conversion.

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Pyrolysis with partial combustion of oil shale fines from the Irati Formation in Brazil has been investigated in a 30 cm diameter spouted bed reactor. Experiments were carried out at atmospheric pressure and temperatures between 450 and 600°C. The oi] shale particle size was less than 6.35 mm. Spouting gas temperatures ranged from 20 to 565°C. Three inlet gas pipe diameters and two spouted bed heights were studied. Operation of the process was found to be stable over a wide range of test conditions. Results are presented for oil and gas quality, efficiency of retorting and overall performance of the plant.

Jute fiber is the second most common natural cellulose fiber worldwide, especially in recent years, due to its excellent physical, chemical and structural properties. The objective of this paper was to investigate: the thermal degradation of in natura jute fiber, and the production and characterization of the generated activated carbon. The production consisted of carbonization of the jute fiber and activation with steam. During the activation step the amorphous carbon produced in the initial carbonization step reacted with oxidizing gas, forming new pores and opening closed pores, which enhanced the adsorptive capacity of the activated carbon. N 2 gas adsorption at 77K was used in order to evaluate the effect of the carbonization and activation steps. The results of the adsorption indicate the possibility of producing a porous material with a combination of microporous and mesoporous structure, depending on the parameters used in the processes, with resulting specific surface area around 470 m 2 .g -1 . The thermal analysis indicates that above 600°C there is no significant mass loss.

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