三氯乙酸与其他有机物在活性炭上的竞争吸附

Competitive adsorption of trichloroacetic acid and other organic compounds on activated carbon

通过等温吸附实验,考察了三氯乙酸(TCAA)与十二烷基苯磺酸钠(DBS)、腐殖酸(HA)在活性炭(GAC)上的竞争吸附现象。结果表明,GAC对TCAA的吸附符合Langmuir模型,对DBS和HA的吸附均符合Freudlich模型;在GAC上,DBS和HA对TCAA构成竞争吸附,大分子HA阻塞GAC的微孔,使得TCAA与DBS难以进入微孔;GAC对3种物质的吸附能力由大到小依次为DBS、TCAA和HA;离子型表面活性剂DBS憎水性一端与TCAA竞争吸附位,亲水性一端与TCAA形成吸附,使GAC总饱和吸附量有所加大。

By the means of isothermal adsorption experiment,competitive adsorption of trichloroacetic acid （TCAA） and dodecyl benzene sulfonate（DBS）, as well as humic acid（HA）, on the granular activated carbon was investigated. The results showed that GAC adsorption isotherm of TCAA corresponded with Langmuir model, while GAC adsorption isotherms of DBS and HA corresponded with Freudlich model. DBS and HA had a competitive adsorption with TCAA on GAC. Macromolecules of HA blocked the micropores of GAC,thus it was difficult for TCAA and DBS to enter into the micropores. Among DBS,TCAA and HA, the GAC adsorption capacity gradually reduced. The hydrophobic end of ionic surfactants（DBS） competed with TCAA for the adsorption sites,while the hvdroDhilic end absorbed TCAA.thus the saturated adsorotion of GAC increased.