苯的衍生物在活性炭水界面上的吸附标准自由能及与其分子结构的关系赵振国

:0253-2468(2001)-01-0029-05　　　:O647.3　　　:A/赵振国　(,　100871):25℃、、、-、、-、-、、-、-、-、-,Langmuir.LangmuirΔG0.,ΔG0,ΔG0.ΔG0.:;;;;TherelationshipbetweenchangesofstandardfreeenergyinadsorptionandmolecularstructureofbenzenederivatesZHAOZhenguo　(DepartmentofChemistry,PekingUniversity,Beijing　100871)Abstract:Theadsorptionisothermsofbenzene,phenol,aniline,p-chloroaniline,benzoicacid,p-hydroxybenzoicacid,p-chlorophe-nol,nitrobenzene,p-aminobenzoicacid,p-nitrophenol,p-nitroaniline,p-nitrobenzoicacidfromwaterontoactivecarbonweredeter-minedat25℃.TheisothermscanberepresentedbytheLangmuirequation.ThechangeofstandardfreeenergyΔG0inadsorptionprocesswascalculatedfromLangmuirparameters.ThecalculatedresultsshowedthateachfunctionalgroupcanbeassumedtomakeitsowncontributiontoΔG0ofamolecule.Therelationshipofthemolecularweight,andthemolecularconnectivityindextotheΔG0wastested.Keywords:adsorption;activecarbon;benzenederivate;thermodynamicsofadsorption;molecularconnectivityindex:1999-12-30;:2000-07-20:(1937—),,,、、、、,.,[1].,,.().,、、.,,[2]..,60,4(S、L、HC)[3],Langmuir、Freundlich、BETD-R.,.、./,Langmuir21120011　　　　　ACTASCIENTIAECIRCUMSTANTIAEVol.21,No.1Jan.,2001DOI:10.13671/j.hjkxxb.2001.01.006ΔG0,ΔG0.1　1.1　、、、A.R.,.、-、-、-A.R.,.-、-、-、-A.R...,、,BET1410m2·g-1,0.8nm.1.2　[4].ns:ns=V(c0-c)/m.Vm,c0c.24h.,.:25℃.2　2.1　11Langmuir,Lang-muir:ns=nsmbc/(1+bc)(1)c/ns=1/(nsmb)+c/nsmnsm,b.nsmb1.1　,/ΔG0Table1　Physico-chemicalparameters,adsorptionconstantsatactivecarbon/waterinterfaceandΔG0forbenzenederivatesMCs,g·(100mL)-1nsmmmol·g-1b,L·mol-1Am,nm2·-11χν-ΔG0,kJ·mol-178.10.1834.0032800.52.0025.094.19.481.685001.222.1425.293.15.060.91226002.212.2026.2-128.62.960.27349352.792.6126.7122.10.3432.87106000.702.5726.9-138.10.6442.08137000.972.726.9-127.60.1001.12234501.792.6827.8123.10.2004.594500.452.4528.0-137.11.501.12395351.792.7728.1-139.11.630.52886653.872.5828.2-138.10.1001.7422901.182.6529.3-167.10.0281.45631801.392.8529.9　　:Cs“SolubilitiesofInorganicandOrganicCompounds”(H.Stephen,T.Stepheneds.)　　1nsmCs,、,nsmCs(1),,.30　　　　　　　　　　2110,[5].1　nsmCSFig.1　Limitingadsorbedamountnsmvs.solu-bilitiyCs　　nsmAm(1)0.4nm2[6].,,.2.2　ΔG0,K=xsfs/xfxxs,ffs.,,f=1,fs=1.xxsccs.ΔG0=-RTlnK=-RTln(cs/c)(2)AlexanderΓt[7]:ΔG0=-RTln(Γ/tc)(3)　　Γns,Γ=ns/S(S)ΔG0=-RTln(ns/cSt)(4)Bartellns/c[5],ΔG0=-RTln[(ns/c)c※0/St](5)　　,fs=1;,.,Langmuir.,bc1,(1),ns/c=nsmb,(4)[8]:ΔG0=-RTln(nsmb/St)(6)　　,nsmb,.,[2],(6)tvanderWaals0.37nm[6].1nsmbΔG01.1ΔG0,.,ΔG01mol1mol·L-11mol·L-1.,-ΔG0.,,.(,311:/)[9,10].112、、、、.,ΔG0,,ΔG0=∑niΔG0i,ΔG0iiΔG0,nii.ΔG0ΔG0i,2.2　ΔG0iTable2　Thestandardfreeenergychanges(ΔG0i)offunctionalgroupsofbenzenederivates-ΔG0i-ΔG0iC6H625.025.0-OH0.2--OH00.13--OH0.2-NH21.2--NH21.21.23--NH21.3----ClCl1.51.61.55-------COOHCOOHCOOHCOOH1.91.71.91.91.85-------NO2NO2NO2NO23.03.03.13.03.03　　2,,ΔG0i,ΔG0.,、、、、..ΔG0ΔG0iΔG0.,ΔG0i.2,,.ΔG0.21ΔG0M,:-ΔG0=20.6+0.0542M,　r=0.8932.3　ΔG0:..70、,[11].1χv.1χv1.3-ΔG01χv,:-ΔG0=15.8+4.611χv,　r=0.82332　　　　　　　　　　212　-ΔG0MFig.2　Relationshipbetweenstandardfreeen-ergychangesinadsorptionofbenzenederivatesfromwaterontoactivecarbonandtheirmolecularweight3　-ΔG01χvFig.3　RelationshipbetweenΔG0and1χv　　3,1χv,-ΔG0./1χv,1χv.,.Sabijic[12].:[1]　.[M].:.1991[2]　ChermisinoffPN,EllerbushF(eds).Carbonadsorptionhandbook[M].AnnArborMichigan:AnnArborSciencePublish-erInc.1979[3]　GilesCH,MacEwanTH,NakhwaSN,etal.Studiesinadsorption.PartXL[J].JChemSoc,1960:3973[4]　,,..XII[J].,1985,43:813[5]　BartellFE,ThomasTL,FuY.Thermodynamicsofadsorptionfromsolutions.IV[J].JPhysChem,1951,55:1456[6]　IsirikyanAA,KiselevAV.Theabsoluteadsorptionisothermsofvaporsofnitrogen,benzeneandn-hexane,andtheheatsofadsorptionofbenzeneandn-hexaneongraphitizedcarbonblacksI.[J].JPhysChem,1961,65:601[7]　AlexanderAE,JohnsonP.Colloidscience[M].London:OxfordUniversityPress.1949[8]　ZhaoZhenguo,ZhangLanhui,LinYao.Thermodynamicsofadsorptionoforganiccompoundsatthesilicagel/nonpolarsol-ventinterfaces[J].JColloidInterfaceSci,1994,166:23[9]　GuerraMC,BarbaroAM,FortiG,etal.RMValues,retentiontimesandoctanol-waterpartitioncoefficientsofaseriesof5-nitromidazoles[J].JChromatogr,1983,259:329[10]　DavydovVYa,ZhaoZhenguo.Calculationoftheisothermsofadsorptionfromsolutionsaccordingtocontributionofmolec-ulatfragments[J].ZhPhizKhim,1994,68:1084[11]　KierLB,HallLH,Molecularconnectivityinstructure-activityanalysis[M].Letchworth:ResearchStudiesPress,1986[12]　Sablijic,A.Onthepredictionofsoilsorptioncoefficientsoforganicpollutantsfrommolecularstructure:applicationofmoleculartopologymodel[J].EnvironSciTechnol,1987,21:358331:/