球形活性炭的制备及其对苯并噻吩的吸附研究

以122型弱酸性酚醛系阳离子交换树脂为炭前驱体,经过炭化和CO2活化,制备球形活性炭(SAC).利用热重分析、扫描电镜、红外光谱和低温N2吸附对材料进行表征.结果表明:制得的球形活性炭比表面积达到799.567 m2/g,孔容为0.969 cm3/g,对苯并噻吩的吸附硫容达到10.3mg/g.用Freundlich和Langmuir模型对吸附平衡数据进行拟合发现:球形活性炭对苯并噻吩的吸附更符合Freundlich模型,表明球形活性炭的吸附活性位不均匀分布;分别用准一级(PFO)、准二级(PSO)、修正的准n级(MPnO)和混阶(MOE)四种动力学速率方程对吸附动力学数据进行拟合,MPnO最适合描述球形活性炭吸附苯并噻吩的动力学过程.

Synthesis of Spherical Activated Carbon and Its Performance of Adsorptive Desulfurization

Phenolic weak acid cation exchange resin was chosen as carbon precursor to prepare spherical activated carbon（SAC） by carbonization and activation with CO2.The product was characterized by infrared spectrum analysis and N2 adsorption,and the results showed that the specific surface area and pore volume were 799.567 m^2/g and 0.969 cm^3/g,respectively.The saturation capacity for benzothiophene was10.3 mg /g.The equilibrium experimental data were fitted to the Langmuir and Freundlich models,and Freundlich model gave a better correlation,which meants there was heterogeneity in the sites of the SAC adsorbents.Pseudo-first-order（PFO）,pseudo-second-order（PSO）,modified pseudo-n-order（MPnO）and mixed-order rate equation（MOE） were used to fit the kinetics experimental data.The results indicated that MPnO was the best model to describe the kinetics of adsorption of benzothiophene on SAC.