作　　者： ; ; ; ; ;

机构地区： 西安建筑科技大学环境与市政工程学院

出　　处： 《环境工程学报》 2012年第8期2483-2488,共6页

摘　　要： 以5 mol/L HNO3,40%NaOH及5%H2O2对活性炭进行化学改性,采用序批式实验研究了活性炭改性前后对阿特拉津(AT)的吸附平衡特性,并以Langmuir和Freundlich模型对吸附等温线进行了拟合。结合活性炭改性前后孔结构和表面化学的变化特征,探讨了不同改性方法对AT吸附去除的影响效应。结果表明:活性炭经5 mol/L HNO3改性后对AT的吸附性能显著降低;而5%H2O2和40%NaOH改性炭对AT的吸附能力较原炭明显增强,且40%NaOH改性炭的吸附能力大于5%H2O2改性炭。原炭及改性炭对AT的吸附等温线均符合Langmuir模型。HNO3改性炭对AT吸附的降低主要是由于表面酸性基团的增加引起的;H2O2改性炭对AT吸附能力的提高主要是由于比表面积的增大引起的;而NaOH改性炭对AT吸附能力的提高是由比表面积增大和表面碱性基团增加共同作用的结果。几种改性炭和原炭对AT去除率的大小顺序依次为:NaOH改性炭>H2O2改性炭>原炭>HNO3改性炭。 Modified activated carbons （ACs） were prepared by using 5 mol/L HNO3, 40% NaOH, and 5% H202 as modification reagents, respectively. The adsorption isotherms of atrazine onto three modified and o- riginal ACs were obtained using equilibrium batch tests, and Freundlich and Langmuir models were adopted to fit the isotherms. The adsorption behaviors of three modified and orignal ACs were compared based on their pore structure and surface chemistry analysis. Results showed that the adsorption capacity of atrazine by HNO3 modi- fied AC was significantly reduced, but the adsorption capacities of 5% H202 and 40% NaOH modified ACs were significantly increased. Meanwhile the adsorption capacity of H202 modified AC was less than that of NaOH mod- ified AC. The adsorption isotherms of all modified ACs as well as the original one were well fitted with Langmuir model. The adsorption capacity reduction of HNO3 modified AC was mainly due to the increase of surface acidic functional groups, while the adsorption increase of H202 modified AC was mainly attributed to surface area en- largement. Both surface area enlargement and the increase of alkaline functional groups could account for the ad- sorption enhancement of NaOH modified AC. The adsorption capacities for atrazine by the modified and original ACs followed the order of： NaOH modified AC 〉 H202 modified AC 〉 original AC 〉 HNO~ modified AC.

关 键 词： 活性炭 阿特拉津 吸附 改性

领　　域： [环境科学与工程]