摘要
由于持久性有机污染物多环芳烃(PAHs)的高毒性、难降解、远距离迁移特性,使其在环境介质中可产生严重危害,因此,本文研究氨水改性煤基活性炭(CAC)以有效吸附PAHs污染物。通过考察不同氨水浓度、改性温度、处理时间对吸附芘的影响,获得最优改性样品(NCAC)及其最优改性条件:氨水浓度10%,改性温度35℃,处理时间18 h;改性后NCAC比表面积由671.88增加到801.67 mg/g,平均孔径由3.111增加到3.825 nm,表面碱性增加。与CAC相比,改性后NCAC对芘的吸附量显著增加,且吸附行为由单分子层吸附变为多分子层吸附;同时,CAC和NCAC对芘的吸附动力学均符合拟二级动力学方程。上述结果表明:改性的样品NCAC是很好的吸附剂,可以高效快速、大容量地吸附芘污染物,将有很好的应用前景。
Because of persistent organic pollutants polycyclic aromatic hydrocarbons（PAHs） with high toxicity, hard degradation,and long distance migration characteristics, which lead to serious hazard in environmental medium, so coal- based activated carbon（CAC） was modified by ammonia to effective adsorption of PAHs pollutants. The effects of various ammonia concentration,modification temperature, and treatment time on adsorption pyrene were studied. The optimal modified CAC was noted NCAC and the suitable modification conditions were obtained as ammonia concentration 10%, modification temperature 35 ℃, treatment time 18 h. The surface area and average pores size of NCAC increased from 671.88 mg/g and 3.111 nm of CAC to 801.67mg/g mg/g and 3.825, respectively, and the basicity properties of NCAC enhanced. Compared with CAC, NCAC was highly effective in adsorbing pyrene and pyrene adsorption behavior from the monolayer becomes to multilayer; moreover, the adsorption kinetics of pyrene onto CAC and NCAC were both described by the pseudo- second- order kinetic model well. The modified sample is a good absorbent and can adsorb PAHs effectively and fast from aqueous solution, which has a good application prospect.
出处
《石河子大学学报（自然科学版）》
CAS
2016年第1期92-99,共8页
Journal of Shihezi University(Natural Science)
基金
国家自然科学基金项目(51262025)
兵团国际合作项目(2013BC002)
关键词
煤基活性炭
氨水
改性
芘
吸附
coal-based activated carbon
ammonia
modification
pyrene
adsorption
