中文摘要：

采用低温急速冷冻一真空干燥技术制备了PACl-HA絮体的粉末样品，研究了这些样品的物理与分形特征．结果表明，PACl-HA絮体具有无定形结构，主要组成元素为C、O、Al，所含特征官能团保留了絮体组成原料的一些特征；絮体的BET比表面积为130～161m^2·g^-1，BJH累积吸附孔体积为0．38～0．52cm^3·g^-1，BJH脱附平均孔径为7．7～9．6nm，PSD峰值对应孔径8．4～11．2nm．PACl-HA絮体具有自相似性的粗糙表面，呈现多尺度分形特征；图象法和N2吸附／脱附等温线法确定的表面分形维数D。分别为2．03～2．26、2．24～2．37，前者的分形尺度大约处于23～390nm之间，主要属于絮体外表面尺度，而后者的分形特征尺度区间的下限大约为0．2nm，属于孔表面尺度；另外．对同一絮体，N2吸附法和脱附法确定的孔表面分形维数不同．热力学模型计算出的D；远大于3，与Sahouli等的研究不符．

英文摘要：

The powder of polyaluminum chloricle-humic acid （PAC1-HA） floes was prepared by cryo-freezing-vacuum-drying method. These floes were characterized by X-ray diffractometry, FTIR spectroscopy, elementary analysis and surface area determination. The results show that these floes are amorphous, mainly composed by elements of C, O, Al, and reserve some characteristic functional groups from PACl, HA or Kaolin. The N2 absorption-desorption data determined the microstructure of PACl-HA floes： 130 - 161 m^2·g^-1 of BET specific surface area, 0.38--0.52 cm^3·g^- 1 of BJH cumulative absorbed volume and 7.7 - 9.6nm of BJH desorption average pore diameter. The peak values of pore size distribution（PSD） curves were found at 8.4- 11.2nm of pore diameter. The self-similar and rough surface was observed in SEM images of PACl-HA floes. The surface fractal dimensions DS of the floes determined from both SEM images method and N2 absorption-desorption one were 2.03 - 2.26 and 2.24 - 2.37, respectively. The correspondent fractal scale for the former method was 23 -390nm, mainly belonging to exterior surface scales, and the lowest limit of the fractal scale for the latter method was 0.2nm and fell in pore surface scales. This demonstrated that the floes surface had multiscale fractal properties. Furthermore, some difference was given between the pore surface fractal dimensions Ds calculated from N2 absorption data and desorption data. The calculated pore surface Ds values of much more than three through thermodynamic model had discrepancy from Sahouli et al＇s results.