Analysis of Char Specific Surface Area and Porosity from the Fast Pyrolysis of Biomass and Pulverized Coal

Abstract:

In this paper, the chars of wood dust, corn straw, rice husk and coal pulverized were obtained at different residual time of various pyrolysis temperature (1173 K, 1273 K and 1373 K) during the process of flash pyrolysis in the drop tube furnace (DTF). In order to obtain the parameters of porous structure which included specific surface area, pore volume and fractal dimension of char, low-temperature nitrogen adsorption method was employed to obtain nitrogen adsorption isotherm of chars sample. For the four chars, the corn straw char had the biggest specific surface area and pore volume, the rice husk in second place, the wood dust in third place, and the pulverized coal char in the last one. By taking Frenkel-Halsey Hil (FHH) method to analyze the fractal character of char surface structure, we found that the fractal dimension of biomass except wood char is higher than those of pulverized coal char.

• Periodical: Advanced Materials Research (Volumes 608-609)
• Pages: 383-387
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.608-609.383
• Online since: December 2012
• Authors: Ji Yi Luan, Xue Mei Wu, Gui Fu Wu, Dong Wei Shao
• Keywords: Biomass, Char, Fractal Dimension, Porous Structure, Specific Surface Area

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