活性炭表面热氧化对其吸附二苯并噻吩性能影响

本文主要研究活性炭表面氧化对其吸附二苯并噻吩性能的影响。将活性炭在不同低温下氧化制得表面氧化活性炭，用静态吸附法进行了二苯并噻吩在初始及氧化活性炭上的吸附等温线，应用Langmuir方程对吸附等温线进行拟合，用漫反射红外谱（DRIFTS）表征活性炭表面含氧基团，用Boehm滴定测定活性炭表面官能团含量，讨论了活性炭表面化学性质对其吸附二苯并噻吩的影响。结果表明：活性炭表面酸性含氧基团对二苯并噻吩的吸附有重要影响，酸性含氧基团越多，其吸附量越大。低温气相氧化活性炭提高了活性炭表面酸性含氧基团，提高了其对二苯并噻吩的吸附。氧化温度越高，其表面含氧基团含量越多，其对二苯并噻吩的吸附量也越大。Langmuir吸附等温线可适用于描述二苯并噻吩在活性炭表面上的吸附。

Effect of thermal oxidation of activated carbon surface on its adsorption of dibenzothiophene

The effect of thermal oxidation of activated carbon surface on its adsorption of dibenzothiophene was investigated.The surface oxidation of the activated carbon was carried out by heating at different temperatures in the air.Static equilibrium adsorption experiments were conducted to determine the isotherms of dibenzothiophene on the original and oxidized activated carbons.The type and concentration of oxygen functional groups on the activated carbons were determined by diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and Boehm titration respectively.The influence of the surface chemistry of the activated carbons on the adsorption capacity for dibenzothiophene was discussed.The results showed that the acid oxygen-containing groups of the activated carbon surfaces played an important role in enhancing the adsorption of dibenzothiophene.It was shown that the use of thermal oxidation could increase the concentration of oxygen-containing groups on the activated carbon surfaces,and consequently increase its adsorption capacity for dibenzothiophene.It was also found that the higher the oxidation temperature,the more the oxygen-containing groups on activated carbon surface,which enhanced the adsorption capacity of dibenzothiophene on its surfaces.The Langmuir equation was shown to fit well these isotherms.