应用浸渍法,采用Fe³⁺、Cu²⁺ 和Ag⁺ 对高比表面活性炭( AC) 进行改性,制备出3种改性的AC(Fe³⁺ / AC、Cu²⁺ / AC 和Ag⁺ / AC). 采用静态吸附法测定改性AC 吸附乙腈溶液中二苯并噻吩(DBT) 的吸附等温线,应用程序升温脱附法( TPD) 测定DBT 在未改性AC 及3 种改性AC 上的脱附峰面积,并采用Boehm 滴定法测定这4 种吸附剂的表面总酸性基团含量. 结果表明:与未改性的AC 相比,Fe³⁺ / AC、Cu²⁺ / AC 和Ag⁺ / AC 表面的总酸性基团含量增加,其对乙腈溶液中DBT 的吸附容量也增大;各吸附剂表面的总酸性基团含量顺序为Fe³⁺ / AC>Cu²⁺ / AC>Ag⁺ / AC>未改性AC,它们对乙腈溶液中DBT 的吸附能力在298K 下分别提高了30%、20%、14%. 以上结果表明AC 类吸附剂的吸附容量与其表面的酸性基团含量成正比;应用浸渍法可提高吸附剂表面的酸性基团含量,从而增加吸附剂表面吸附乙腈溶液中DBT 的吸附活性位,提高对DBT 的吸附能力.

In this paper, first, activated carbon (AC) with high specific surface area was modified with metal ionsFe³⁺,Cu²⁺ and Ag⁺ through an impregnation process, and three kinds of modified AC, namely, Fe³⁺ / AC, Cu²⁺ / ACand Ag⁺ / AC, were prepared. Next, the products were used to adsorb the dibenzothiophene (DBT) in acetonitrilesolution, and the corresponding isotherms were obtained by means of the static adsorption method. Then, the de-sorption peak areas of DBT desorbed from the AC before and after the modification were measured through tempera-ture-programmed desorption (TPD) experiments. Finally, the total amount of acidic functional groups on the sur-faces of these four kinds of AC was measured via the Boehm titration. The results show that, after the modification,both the total amount of acidic functional groups and the adsorption capacity for DBT increase, that the total amountof acidic functional groups follows the order of Fe³⁺ / AC>Cu²⁺ / AC>Ag⁺ / AC>AC, with the adsorption capacity re-spectively increasing by 30%, 20% and 14%. It is thus concluded that the adsorption capacity of AC absorbents isproportional to the total amount of acidic functional groups, and that the loading of Fe³⁺,Cu²⁺ and Ag⁺ on AC en-hances the adsorption of DBT in acetonitrile solution due to the increase of active sites on AC surfaces for DBT ad-sorption.