腐殖酸自水溶液中吸附亚甲基蓝的热力学与机理研究王红斌

:1004-1656(2002)04-0449-03王红斌1,杨　敏1,宁　平2,陈毅坚1(1.,　650031;2.,　650031):;;;:O647.314　　:A　　　　　,,、、、,、、,、。,。[1～3]ΔG、ΔH、ΔS,。,,。1　1.1　(),,1。1:、、,。,,。,HCl+HF。1.2　,200,180℃2h,。、、、、。721(),HQ45A-Ⅱ()。1.3　,800mg/L。665nm,,,。,,,,,,。pH:pH2.5～11.5,50mlpH,,25℃,,。:。,,,。1　Table1　Thebasiccharactersoftwokindsofhumicacid(%)(%)(mmol/g)(mmol/g)(mmol/g)(m2/g)3017.895.221.623.6055.701414.794.920.624.3093.0614420028　　　　　　　　　　　　ChemicalResearchandApplication　　　　　　　　　　　　Vol.14,No.4Aug.,2002:2001-11-12;:2002-05-242　2.1　1,25℃,3,4,4。,,5。图1　25℃时的吸附速率曲线Fig.1　Theadsorptionratecurveat25℃2.2　pHpH3～12。,5,pH3.48,,。图2　pH值对吸附的影响Fig.2　InfluenceofpHonadsorptioncapacity2.3　pH,pH。3,Lagergren:ln(Am-At)=lnAm-katAm、Att,ka。ln(Am-At)t,,,ka,ka2981.113h-1,ka2980.961h-1,。图3　吸附动力学曲线Fig.3　Theadsorptionkineticcurve图4　腐殖酸吸附亚甲基蓝的吸附等温线Fig.4　Adsorptionisothermsofthetestedmethylenceblueontohiumicacid图5　腐殖酸吸附亚甲基蓝的Langmuir方程拟合曲线Fig.5　Nonlinearregressioncurvesforadsorptionofmethylenceblueontohiumicacid2.4　(4)。Langmuir:Ce/A=1/(bAm)+Ce/Am,5,,Langmuir。Ce/A～Ce,Amb。ΔG、ΔH、ΔS[1-3]:450化学研究与应用　　　　　　　　　　　　　第14卷ΔG=-RTlnAmbstlnb1b2=ΔHR1T2-1T1ΔH=ΔGt-TΔGTpΔS=ΔH-ΔGTAmbLangmuir,s,t,,,,,,,17。2。2　Table2　ThecalculationalresultsoftheadsorptiveconstantandthermodynamicparametersintheadsorptionprocessT(K)298318298318Am(mg·g-1)128.21136.9974.07102.04b(L·mg-1)0.1770.1820.11270.0553ΔG(kJ·mol-1)-46.52-49.71-45.40-46.56ΔH(kJ·mol-1)1.03-28.07ΔS(J·mol-1·K-1)159.5758.16　　,,。、、、,,,,,,,、,ΔH0。,,,,,。17×7.6×3.25×10-30m3,1.12,,1mol6mol,,ΔS0。,,,,。:[1].(HUAXUEYANJIUYUYINYONG)[J],2001,13(6):599-604.[2],,.[J],1985,43:813—818.[3],.[J],1983,41(12):1091—1099.[4],,.(HUAXUEYANJIUYUYINYONG)[J],1997,9(2):155-157.[5]StudebakeML.Ind.Eng.Chem.[J],1956,48:162.[6]GreenlandDJ.J.Soil.Sci.[J],1964,15:178.[7]BartellFE,ThomasTL,FuY.J.Phy.Chem.[J],1951,55:1456.StudyonmechanismandthermodynamicsofmethylenceblueadsorptionfromaqueoussolutionbyhumicacidWANGHong-bin1,YANGMin1,NINGPing2,CHENYi-jian1(1.DepartmentofChemistry,YunnanUniversityoftheNationalities,Kunming650031,China;2.SchoolofEnvironmentalScienceandEngineering,KunmingUniversityofScienceandTechnology,Kunming650031,China)Abstract:ThispaperstudiesthecharacteristicsandmechanismoftheadsorptionofmethylencebluefromaqueoussolutionbyhumicacidwhichwasextractedfromswampysoilinZhongdianofYunnanintwomethods.Theresultshowsthattheadsorptioncouldfitthelangmuirmodel.Humicacidsextractedintwomethodshasthesimilarpatternofadsorption,buttheHumicacidbysodiumpyrophosphatehasbetterad-sorptionbecauseofitsbiggerspecificsurfacearea.Theadsorptiveconstantandthermodynamicparametershavebeenevaluatedindifferenttemperatures.Furthermorethemechanismofadsorptiononthehumicacidhasbeendiscussed.Keywords:swampysoil;humicacid;methylenceblue;adsorptionthermodynamics(责任编辑　童冬梅)451第4期　　　　　王红斌等:腐殖酸自水溶液中吸附亚甲基蓝的热力学与机理研究