Synchrotron X-ray microtomography and multifractal analysis for the characterization of pore structure and distribution in softwood pellet biochar

作     者：Franziska Srocke Liwen Han Pierre Dutilleul Xianghui Xiao Donald L.Smith Ondřej Mašek 

作者机构：Department of Plant ScienceMacdonald CampusMcGill University21111 Lakeshore RoadSte-Anne-de-BellevueQuebec H9X 3V9Canada UK Biochar Research CentreSchool of GeosciencesUniversity of EdinburghKing’s BuildingsAlexander Crum Brown RoadEdinburgh EH93FFUK Advanced Photon SourceArgonne National LaboratoryLemontIL 60439USA Present Address:National Synchrotron Light Source IIUptonNY 11973USA 

出 版 物：《Biochar》 (生物炭（英文）)

年 卷 期：2021年第3卷第4期

页      面：671-686页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：The research leading to these results received funding from BiofuelNet Canada(funded by the Canadian Networks of Centers of Excellence)and the Leverhulme Trust 

主　　题：Biochar Pore structure X‐ray microtomography Homogeneity Isotropy Multifractal analysis 

摘      要：Biochar pores in the micrometer range(1-100μm)derive from cellular structures of the plant biomass subjected to pyrolysis or can be the result of mechanical processing,such as *** this study,synchrotron X-ray microtomography was used to investigate the internal pore structure of softwood pellet biochar produced by slow pyrolysis at 550 and 700°*** microtomographic data sets consisted of 2025 images of 2560×2560 voxels with a voxel side length of 0.87μ*** three-dimensional reconstructions revealed that pelleting and pyrolysis significantly altered the pore structures of the wood feedstock,creating a network of connected pores between fragments that resembled the wood *** higher pyrolysis temperature increased the specific surface area(as determined by BET nitrogen adsorption),it did not affect the total observed *** analysis was applied to assess the characteristics of the frequency distribution of pores along each of the three dimensions of reconstructed images of five softwood pellet biochar *** resulting singular-ity and Rényi spectra(generalized dimensions)indicated that the distribution of porosity had monofractal scaling behavior,was homogeneous within the analyzed volumes and consistent between replicate ***,the pore distributions were isotropic(direction-independent),which is in strong contrast with the anisotropic pore structure of *** pores at the scale analyzed in this study are relevant,for example,for the supply of plant accessible water and habitable space for microorganisms,our findings combined with the ability to reproduce biochar with such pore distribution offer substantial advantages in various biochar applications.