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Bio-based activated carbon is a promising porous material for the use in electrodes for supercapacitors due to its low-cost production, high surface area with controllable pore structure and better thermal properties. Apart from activation type and conditions, the content of lignocellulosic biomass (namely cellulose, hemicellulose and lignin) is also a critical parameter on textural properties of activated carbon. In the present study, glycerol organosolv treatment was applied to fractionate lignin and cellulose from hazelnut shells. Hazelnut shell, lignin and cellulose-rich pulp mixed separately with KOH at a ratio of 1:2, and each mixture was activated for 1 h at 800 °C. FTIR results showed that lignin-based (AL) and cellulose-based activated carbons (AC) had more oxygen-containing functional groups, while AL had more aromatic structure. While activated carbon of hazelnut shell (ANS) had the highest specific surface area (1052.2 m2/g) and micropore volume (0.427cm3/g), AC had the least specific surface area (319.07 m2/g) and micropore volume (0.107cm3/g). While AL and ANS had microporous structure, AC was classified as mesoporous activated carbon. Due to high amount of oxygen-rich surface functional groups, high specific surface area and pore diameter of higher that 1 nm, activated carbon of hazelnut shell is a good candidate to be used as an electrode material. But, since the specific surface area and pore diameter are not the only factors that affect the capacitance, future work will include an electrochemical performance test to ANS, AL and AC.

A shrinking-layer model by modification of classical shrinking-core model was developed based on cell wall multi-layered structure for delignification of sugarcane bagasse with sulfuric acid (SA) catalyzed atmospheric acetic acid (AA) fractionation. The general model for overall rate of delignification was obtained and further employed to evaluate the mass transfer effects on delignification. It was found that the external diffusion could be neglected under the studied fractionation conditions, while the internal diffusion appeared to play an important role. The effective diffusion coefficient for lignin within the biomass was estimated as 6.7 × 10 −14 –1.6 × 10 −12  m 2 /s depending on temperature, solid content in the system and molecular weight of lignin. However, surface reaction also seems to be a limiting step to the overall rate of delignification. At the early stage of delignification, both internal diffusion and reaction were controlling steps, while at the late stage reaction seems to be the controlling step. [ABSTRACT FROM AUTHOR]