活性炭的改性及其对苯酚吸附行为的研究

通过正交试验的方法，优化活性炭的改性条件；并以活性炭为载体，氢氧化钠溶液为改性剂，在最优条件下制备改性活性炭；测定了改性前后活性炭的比表面积及表面酸性官能团的含量；考察了改性前后活性炭对苯酚的吸附行为。结果表明，在NaOH溶液浓度为0．1mol／l，浸渍时间为3h，活化时间为3h，活化温度为400℃的情况下，改性活性炭吸附效果最佳，苯酚吸附量为149．05mg／g，比未改性活性炭的吸附量提高了61．97％；NaOH-改性活性炭的比表面积为1046．10m2／g，比未改性活性炭的比表面积增加了12．42％，改性后表面的酸性基团含量降低，碱性增强；Freundlich和Langmuir二种等温线模型均能较好的反应活性炭对苯酚的吸附行为，其中Freundlich模型更为理想。

STUDY ON THE MODIFICATION OF ACTIVATED CARBON AND ITS ADSORPTION BEHAVIOR FOR PHENOL

In order to develop high- performance carbon, the orthogonal test was used to optimize the conditions of modification. Meanwhile, the carbon as a carrier was modified with sodium hydroxide solution under the optimal conditions. The amount of total surface acidic functional groups and BET surface were deter- mined. And the adsorption behavior for phenol was inspected. The results show that under the conditions of NaOH concentration of 0. lmol/1, soaking time for 3 h, activated time for 3 h and activated temperature of 400℃ , the best removal rate could be obtained, the adsorption of phenol was 149.05 mg/g and improved 61. 97% compared to that of the unmodified carbon. The BET surface of modified activated carbon was 1 046. 10m2/g and improved 12.42% compared to that of the unmodified carbon. The amount of total surface acidic functional groups was reduced but the alkaline was enhanced. Both Freundlich and Langmuir model of sorption isotherms could reflect the adsorption behavior of modified activated carbon for phenol,while the Freundlich model was more proper.