摘要
研究了CCTS对低浓度游离酸的吸附特性,基于吸附质-分子探针电位法,考察了吸附剂活性中心数目、游离酸种类和温度对吸附行为的影响。结果表明,在30℃时,CCTS吸附游离酸的过程,遵循单分子层机理进行吸附。吸附剂―吸附质相互作用能U制约表观吸附速率常数K,K、U大小分别为2.519×10-2,4.084×10-2,9.398×10-2L/min和7.264,7.420,7.926 kJ/mol,两者存在线性相关性,呈逐渐增大趋势。K、U大小随着活性中心数目G的增加而增大。CCTS吸附游离酸为吸热过程,吸附表观活化能Ea为33.98 kJ/mol。3种类型游离酸K、U的大小顺序为:HClO4>HNO3>H2SO4,吸附分维数Dw分别为1.384、1.567、1.911,Dw值越大,导致表观吸附速率常数降低。
Cross-linked chitosan as a novel adsorbent material was studied. An experiment on adsorption of three kinds of low concentration free acid on cross-linked chitosan microspberes, which was prepared at the laboratory, was conducted by using the adsorbate-molecular probe-electric potentiometric method. The experiment showed that adsorption of free acids on the cross-linked chitosan followed the mechanism of monomolecular adsorption and was an endothermic process with the apparent adsorption activation energy of 33.98 kJ/mol. According to the experiment, there was a linear relationship between K （the apparent adsorption rate constant） and U（the adsorbent-adsorbate interaction energy constraint）, and both K and U increased with the increase of G（the adsorbent activity center number）. In addition, it was found the increased Dw（the adsorption fractal dimension） would lead to decreases of the apparent adsorption rate constant.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2012年第8期51-55,共5页
Environmental Science & Technology
基金
广东省自然科学基金(S2011010001556)
广州市科技计划项目(11C56040056)
关键词
CCTS
吸附质-分子探针
表观吸附速率常数
吸附剂-吸附质相互作用能
吸附分维数Dw
cross-linked chitosan microsphere
adsorbate-molecular probe
apparent adsorption rate constant
adsorbent- adsorbate interaction energy
adsorption fractal dimension
