氧等离子体改性竹活性炭对苯胺的吸附特性

对氧等离子体改性前后的竹活性炭表面理化性质的改变及其对水溶液中苯胺的吸附特性进行了研究.结果表明,氧等离子体改性竹活性炭的表面物理性质变化较小,但是表面化学性质的变化十分显著.在实验条件下,当溶液pH值超过5.0以后,3种竹活性炭对苯胺的吸附效率达到最大并基本保持不变.吸附动力学研究表明,3种竹活性炭对苯胺的吸附过程均可以在480min内达到平衡,改性竹活性炭的苯胺平衡吸附量显著大于未改性炭,吸附过程均可以用准二级动力学模型和内部颗粒扩散模型进行描述.吸附等温线研究表明,3种竹活性炭对苯胺的吸附等温线均符合Langmuir模型.进一步的分析表明, π-π色散力和氢键作用的增强可能是导致改性竹活性炭吸附苯胺性能提高的主要原因.

Adsorption of aniline by oxygen plasma modified bamboo-based activated carbon

Effects of oxygen plasma modification on the surface properties of bamboo-based activated carbon (BAC) were investigated. The adsorption behaviors of aniline on raw and modified BACs were also examined under various experimental conditions. It was observed that the surface textural properties of modified BACs were almost unaffected, whereas their surface chemical properties changed greatly. Batch experimental results showed that the aniline adsorption efficiency of all BACs reached their peak values at solution pH beyond 5.0, the adsorption equilibrium of aniline on all BACs could be reached within 480min. The modified BACs significantly outperformed raw BAC for the adsorption of aniline. The kinetic and equilibrium data of all BACs could be best described by the pseudo-second-order model, intra-particle diffusion model and Langmuir isothermal model. Further analysis indicated that the improvements of π-π dispersive interaction and hydrogen bond effect were the possible reasons for the better aniline adsorption performance of modified BACs.