低温等离子体改性活性炭纤维对不同极性苯系物的吸附

探究了不同改性时间下的活性炭纤维孔结构和表面化学性质的变化，并进一步研究了改性后的活性炭纤维对不同极性苯系物的吸附。通过BET比表面积、Boehm滴定分析、FTIR红外光谱对改性前后的活性炭纤维进行表征。结果表明，功率150 W，改性时间为30、60和90 min时，活性炭纤维烧失率随着改性时间延长而升高，分别达到16.5%、27.8%、45.5%。改性过程中，活性炭纤维比表面积和微孔孔容显著增加，有助于改善活性炭纤维吸附性能。在物理吸附和化学吸附作用下，改性活性炭纤维对邻二甲苯、间二甲苯和对二甲苯吸附性能有所提高，其中，改性90 min活性炭纤维对其吸附量分别增加了0.58、0.55和0.44 mg·mg-1。酸性含氧基团由原来的0.973 mmol·g-1增加到1.675 mmol·g-1，改性后酸性含氧官能团的增加使活性炭纤维表面极性增大，有利于对极性有机物邻、间二甲苯吸附量增加率的提高。

Adsorption of different polarity BTEX on non-thermal plasma modified activated carbon fiber

We explored the changes in pore structure and surface chemical properties of activated carbon fiber (ACF) with different modification times, and demonstrated the adsorption of benzene, toluene, ethylbenzene, and xylenes (BTEX) of different polarities on modified ACF. The ACF was characterized using the Brunauer-Emmett-Teller (BET) theory, Boehm titrations, and Fourier transform infrared spectroscopy (FTIR). With a power of 150 W, modification times of 30 min, 60 min, and 90 min were used. Under these conditions, the ACF burn-off rate increased gradually with longer modification times, reaching 16.5%, 27.8%, and 45.5%, respectively. During the modification process, the specific surface area and micropore volume of the ACF increased significantly, thus contributing to the increased adsorption capability of the ACF. In terms of physical and chemical adsorption, the adsorptive capacities of p-xylene (PX), o-xylene (OX), and m-xylene (MX) on the ACF modified for 90 min increased by 0.55 mg·mg-1, 0.44 mg·mg-1, and 0.58 mg·mg-1, respectively. Furthermore, the acidic oxygenous group contents of the modified ACF increased from 0.973 mmol·g-1to 1.675 mmol·g-1, thus increasing the ACF surface polarity, while being beneficial for raising the increment rate of adsorptive capacity of polar organics such as OX and MX.