摘要
以菲为目标污染物,研究了粉末活性炭(PAC)在微尺度(1～100 μm)下的粒径效应对多环芳烃吸附性能的影响.实验中按照中值粒径将研磨后得到的粉末活性炭划分为:PAC-1(19 μm)、PAC-2(46 μm)、PAC-3(76 μm).通过比表面积及孔隙度自动分析仪、原位拉曼光谱、扫描电镜等手段对PAC物化性质进行表征,发现粒径减小使PAC的BET比表面积和总孔容增加了10%～20%左右,而对PAC表面化学性质的影响较小.PAC的粒径分布对其吸附性能有显著影响,这种影响主要体现为吸附速率成倍的增加,其次是吸附容量有30%～36%的增幅.分别用3种动力学模型对吸附过程进行拟合,结果表明,伪二级动力学方程的拟合程度最高,PAC-1有最大的吸附速率常数k,并且随着粒径的减小,k值逐渐增大.
Taking phenanthrene as target pollutant, the effect of powered activated carbon （PAC） particle size in the range of 1 - 100 μm on adsorption kinetics of aqueous polycyclic aromatic hydrocarbons was investigated. PAC samples with different median particle diameters were obtained through grinding： PAC-1 （19 μm）, PAC-2 （46 μm）, and PAC-3 （76 μm）. The physiochemical characteristics of original and three ground PACs were determined by surface area and porosity automatic analyzer, Raman spectroscopy and SEM-EDX, respectively. The results showed that with the decrease of particle size, surface area （BET） and micropore volume of PACs increased 10% - 20% , but no significant change on surface chemical properties was observed. Adsorption property differed markedly between three ground PACs, which was indicated by dramatic increase of adsorption rate and the significant increase of adsorption capacity with the decrease of particle diameter. Three kinetic equations were adopted to fit the kinetics data, and pseudo second-order equation matched the data best. PAC- 1 had the highest adsorption rate, and with the increase of particle size, the adsorption rate constant （k） decreased.
出处
《环境科学学报》
CAS
CSCD
北大核心
2013年第1期67-72,共6页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.50878204)
国家重点基础研究发展(973)计划(No.2011CB933704)~~
关键词
粉末活性炭(PAC)
吸附
粒径效应
菲
动力学
powered activated carbon （PAC）
adsorption
particle size effect
phenanthrene
kinetics
