石油焦系活性炭2-甲基噻吩吸附性能研究

Study on adsorption performance of 2-methythiophene on activated carbons from petroleum coke

以石油焦为原料经高温炭化和水蒸气活化处理制备出石油焦基活性炭,经硝酸氧化处理后,采用静态吸附法测试了2-甲基噻吩在石油焦基活性炭上的吸附性能。研究结果显示,制备的活性炭比表面积高于800 m2·g-1,孔容大于0.45 cm3·g-1,经硝酸处理后比表面积和总孔容有所下降。样品经硝酸处理后,对2-甲基噻吩的饱和吸附量显著增加,硝酸处理40 min得到的活性炭对2-甲基噻吩的饱和吸附量最大。2-甲基噻吩在石油焦基活性炭上的吸附动力学均遵循拟二级动力学模型,饱和吸附量随吸附温度的增加而减小,热力学上表现为放热,熵减且是自发进行的过程。

In this work, the activated carbons from petroleum coke were prepared via carbonization and steam activation treatment, and modified by nitric acid treatment. Then, the adsorption performance of 2-methythiophene on activated carbons from petroleum coke were also investigated. The results show that the BET surface areas and pore volumes of activated carbons, are higher than 800 m2·g^-1 and 0.45 cm3·g^-1, respectively, and decrease remarkably after nitric acid treatment. The quantity of 2-methythiophene adsorption by nitric acid-treated carbons increase obviously, and the maximum adsorption capacity is obtained when the treatment time of nitric acid is 40 min. Kinetic studies exhibit that the dynamical data obey well the pseudo-second-order kinetic model. For thermodynamic studies, parameters such as the Gibbs free energy, the enthalpy and the entropy, implied that the adsorption process was spontaneous and exothermic at the temperatures under investigation.