通过水蒸气活化法制备了聚苯乙烯基球形活性炭,并研究了其对二苯并噻吩(DBT)的吸附性能。采用扫描电镜(SEM)、N2吸附、热重分析(TG)以及液相吸附试验考察了球形活性炭的结构特征。结果表明:以苯乙烯离子交换树脂为原料,通过水蒸气活化法,可以得到比表面积979m^2/g-1672m^2/g的球形活性炭。其中,BET比表面积和孔容随活化时间和水蒸气流量的增加而增大,而孔径小于0.7nm的窄微孔却减小。球形活性炭对DBT的吸附量可达109.36mg/g,吸附量与比表面积和总孔容关系不大,而与小于0.7nm的窄微孔成正比。球形活性炭在对DBT的吸附过程中存在不可逆吸附。球形活性炭所含窄微孔的孔容越大,脱附所需要的温度越高,不可逆吸附量越大。
Polystyrene-based activated carbon spheres (PACS) were prepared by steam activation and their adsorption performance to a sulfur-containing dibenzothiophene (DBT) was studied. The textural structure of PACS was characterized by scanning electron microscopy, N2 adsorption, thermal gravimetric, and aqueous adsorption. Results showed that PACS with BET surface areas up to 979-1672m^2/g were obtained. The BET surface areas and pore volumes increased with activation time and steam flow rate except for the vohime of narrow micropores ( 〈 0.7 nm). The maximum adsorption capacity of PACS to DBT was 109.36mg/g and the adsorption capacity was related to the volume of norrow micropores, independent of surface area and total pore volume. Irreversible adsorption existed between DBT and PACS. The larger the volume of the narrow micropores, the higher the desorption temperature and the larger the amount of sulfur retained after heating.