微波改性活性炭吸附1,2-二氯乙烷的性能研究

采用微波高温烧结炉分别在600℃,700℃和800℃下对商业活性炭进行改性,利用比表面积及孔径分析仪、Boehm滴定、傅立叶变换红外光谱比较分析活性炭的比表面积和孔结构、表面官能团等物化性质.以1,2-二氯乙烷为吸附质进行固定床吸附实验.研究表明:改性后活性炭表面酸性基团减少,碱性基团随温度升高增多;比表面积、孔容减小,微孔比表面积增加;活性炭对1,2-二氯乙烷的吸附量排序为:AC-800AC-700AC-600AC-0;灰色关联度分析结果表明:改性活性炭的物理结构特性对吸附量的影响大于表面基团;D-R模型和动力学模型拟合结果都表明活性炭对1,2-二氯乙烷的吸附主要为物理吸附.

Adsorption of 1,2-dichloroethane onto Activated Carbon with Microwave Modification

Activated carbon (AC) was modified with microwave irradiation heating at 600, 700 and 800 °C respectively. The physicochemical properties of the activated carbon were characterized by using Boehm titration, Fourier transformed infrared spectroscopy and Specific surface area and pore size analyzer. Fixed-bed adsorption experiments were conducted by using 1,2-dichloroethane as the adsorbate. The results show that, after microwave modification, the surface acidic functional groups of activated carbon decrease and the surface basic functional groups increase with the increase of temperature. The specific surface area and total pore volume of activated carbon decrease, while the micropore specific surface area increases. The order of the adsorption capacity for 1,2-dichloroethane is AC-800 > AC-700 > AC-600 > AC-0.The results of the grey relativity analysis show that the physical properties of the modified activated carbon have a larger effect on the adsorption capacity than the surface functional groups. The fitting results of D-R model and kinetics equation illustrate that it is a physical adsorption process for activated carbon.