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Abstract：
Activated carbons are synthesized from rice husk by one- and two-step pyrolysis. In general, two-step pyrolysis produces a higher yield of activated carbons. The yield of activated carbon decreases with the increase of mass ratio of KOH and biomass, which has a significant impact on the development of surface area and porosity. The maximum S BET (2138 m2 g-1) is achieved with micro- and mesoporous structures, which is favored for the adsorption process. The activated carbons can efficiently remove phenol from water by a few minutes. In particular, the maximum adsorption capacity (201 mg g-1) is achieved due to the excellent surface textural properties. The Langmuir model can better define the adsorption isotherm. The high correlation coefficient value (R 2 = 0.9991) indicates a monolayer adsorption behavior. The adsorption process can be well-fitted by the pseudo-second-order model. Herein, the phenol molecules pass into the internal surface via liquid-film-controlled diffusion, so the behavior of phenol adsorption onto activated carbons is mainly controlled via chemisorption. In addition, the functional groups on the outer surfaces of activated carbons can attract the phenol molecules onto their internal surface via the \"π-π dispersion interaction\" and \"donor-acceptor effect.\"
摘要：
活性炭是由稻壳通过一步和两步热解合成的。总的来说,两步热解产生较高的活性炭产率。活性炭的产率随着KOH和生物质质量比的增加而降低,对表面积和孔隙率的发展有显著影响。最大SBET（2138m2g-1）是通过微孔和中孔结构实现的，这对吸附过程是有利的。活性炭可以在几分钟内有效地从水中去除苯酚。特别是,由于优异的表面纹理性能，实现了最大吸附容量（201mgg-1）。Langmuir模型能较好地定义吸附等温线。高相关系数值（R2=0.9991）表明单层吸附行为。通过伪二阶模型可以很好地拟合吸附过程。在这里，苯酚分子通过液膜控制扩散进入内表面，因此，苯酚在活性炭上的吸附行为主要通过化学吸附来控制。此外,活性炭外表面上的官能团可以通过“π-π分散相互作用”和“供体-受体效应”将苯酚分子吸引到其内表面上。\"
