Abstract: By applying different pyrolysis temperature and CO2 concentration conditions and using a fixed tube furnace, the present work prepared a series samples of biochar briquettes, whose pore structures and surface fractal dimensions were analyzed by SEM and nitrogen isothermal adsorption, and calculated using FHH method. The relationship between char samples’ pore structure and surface fractal dimension was investigated, as well as the effects of temperature and CO2 concentration on them. The results showed that surface fractal dimension could well characterize pore structural complexity and surface irregularity, as it coincides with content fraction of micropore area and volume, rather than with BET surface area, total pore volume and average pore size. Both BET surface area and surface fractal dimension of biochar briquette reach peak value at 600 ℃ pyrolysis temperature under pure nitrogen. Under the mixed atmosphere of CO2 and N2, the increment of CO2 concentration will lead to gradual increase of BET surface area, but a biphasic (decrease → increase) change in surface fractal dimension with an inflection point of 10% CO2 concentration.
刘泽伟, 闫思佳, 夏子皓, 田霖, 刘煜康, 王竟成, 胡建杭. 温度和CO2对热解成型生物质炭孔隙结构和表面分形维数的影响[J]. 材料导报, 2018, 32(17): 2925-2931.
LIU Zewei, YAN Sijia, XIA Zihao, TIAN Lin, LIU Yukang, WANG Jingcheng, HU Jianhang. Effects of Temperature and CO2 on Pore Structure and Surface Fractal Dimension of Pyrolytic Carbonized Biochar Briquettes. Materials Reports, 2018, 32(17): 2925-2931.
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2018, Vol. 32 
