煤沥青基中孔活性炭的硝酸表面氧化改性研究(英文)

Study on Oxidative Modification of Coal Tar Pitch-based Mesoporous Activated Carbon Surface Using Nitric Acid

采用印刻法制得煤沥青基中孔活性炭,并以硝酸为氧化剂对其进行了表面氧化改性,考察了硝酸浓度、氧化温度和氧化时间对活性炭孔隙结构和表面化学性质的影响。结果表明,活性炭的孔隙结构和表面含氧基团的浓度随氧化改性条件的变化而改变。在硝酸体积分数65%、氧化温度60℃、反应时间3h的最佳条件下,活性炭的平均孔径基本没有变化,比表面积和表面含氧基团的浓度大幅提高,活性炭的中孔率和收率也达到最大值。然而,过度的氧化改性导致了活性炭孔壁的严重坍塌,比表面积和表面含氧基团的浓度明显下降。

Coal tar pitch-based mesoporous carbons （MCs） were prepared by an imprinting method and treated in nitric acid by oxidative modification. The effects of concentration of nitric acid, oxidation temperature and oxidation time on the pore structure and the surface properties of the MCs were investigated. Results show that the pore structure and the surface oxygen-containing groups of the MCs are rolated to the oxidation conditions. Under the optimal oxidation modification conditions of 65% HNOa, oxidation temperature （60 ℃ ） and oxidation time （3 h）, the average pore size of the modified activated carbons （ACs） are essentially unchanged, the specific surface area and the density of the surface oxygeFcontaining groups increased obviously, and the mesopore portion and pitch yield are the highest. However, the excessive oxidation modification led to the serious collapse of the pore walls and decrease of the density of the surface oxygen containing groups on the ACs.