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29 42010 7 ENVIRONMENTALCHEMISTRYVol.29,No.4July 2010 200951. ＊(863)(2006AA06Z320);(50978013);(PHR20100508PHR201008372);(KM200910016009);2009(). ＊＊.pH(MAP)＊王崇臣 郝晓地＊＊ 王 鹏 兰 荔(,,,100044) XRD,IR,TGApHMAP.XRDIR,.,(90.0%)pH7.0—9.0,,(90.0%)pH7.0—7.5. XRD,IR,TGA,,. (MgNH4PO4·6H2O,MAP),(MAP),[1—7]. X(XRD)、(IR)、(TGA)pHMAP,,pHCa2+.1 1.1 A:Ⅰ0.5L5.0mmolNaH2PO4·2H2O;Ⅱ0.5L6.0mmolMgSO4·7H2O15.0mmolNH4Cl.Ⅱ1.5L,Ⅰ,.Mg∶N∶P1.2∶3∶1..pH=7.0,NaOH(NaOH,1mol·l-1NaOH)0.5pH,pH,7.0—11.0.(25℃),.、1h,.,,,().,(25℃). B:,A.:C(Ca2+)=2.17mmol·l-1,C(Mg2+)=1.34mmol·l-1.1.2 (99.0%,Alfa-Aesar). RigakuD/maxⅢAX(CuKα,λ=1.5406A゜,,10°,80°,3°·min-1).Spectrum100FT-IR4000—400cm-1(KBr).ZRY-1P,10℃·min-1600℃,,α-Al2O3.IRISAdvantageICP-AES,DX-120Mg2+、Ca2+NH+4-N.760 292 2.1 XRD ,XRD,1.1,pH7.5—9.0,pH7.0—8.5,(001)、(002)2θ20.85°、33.27°,MgNH4PO4·6H2O(PDF#15-0762),MgNH4PO4·6H2O. ,,pH9.5,,Mg3(PO4)2·4H2O,Mg(OH)2(001)(002),MgNH4PO4·6H2O,Mg3(PO4)2·4H2O、Mg(OH)2,LeCorre[8]XRD.,,pH=9.0,Mg3(PO4)2、Mg(OH)2、Ca3(PO4)2(Ksp=2.1×10-33)CaHPO4(Ksp=1.8×10-7)(001)(002).1 (A)(B)pHXRD1.,2.pH=7.5,3.pH=8.0,4.pH=8.5,5.pH=9.0,6.pH=9.5,7.pH=10.0,8.pH=10.5,9.pH=11.0,10.pH=11.5Fig.1 XRDpatternofprecipitatesobtainedunderdifferentpHinpurewater(A)andtapwatersystem(B) 1,,pH10.5,(001)(002),,.2.2 2pH.2 (A)(B)pHIR1.pH=7.5,2.pH=11.5Fig.2 IRspectrumofprecipitatesobtainedunderdifferentpHinpurewatersystem(A)andtapwatersystem(B) 2,pH=7.5—11.0pH=7.5—10.0 4:pH(MAP)761 455cm-1、568cm-1、1000cm-11430cm-1NH+4[9],pH,,,.,NH+4(1500—1385cm-1),,,,,.2.3 pHTGDTA,3,50℃,[10].100℃,600℃,45%.Frost[11],42%,(7.34%),(34.65%),1mol,4.7mol,.,,,MAP.3 TGDTAFig.3 TGandDTAplotofsomeselectedprecipitates2.4 ,,MAP[5].N、P、Mg1∶1∶1,XRD,pH,PMg,Mg(OH)2(Ksp=5.1×10-12)Mg3(PO4)2(Ksp=1.0×10-24).NH+4(MgNH4PO4,CaNH4PO4).,N.(1): =n×Mm×100%(1),m;n;M. (1),98.9%,(99.0%).,4.4 (%)pHFig.4 EffectofpHonthestruvitecontentsintheprecipitatie762 29 4,pH7.510.5,,,90%pH7.5—9.0,pH10.5,.pH,Ca2+.pH7.07.5,96.8%95.7%.pH7.5,,pH=10.0,15.5%.pH10.5,.2.5 ,pH,,50.12%96.27%(5),MAP.pH,,,AltinbasM[12].pHNH+4-NNH3、[13],,pH.pH.pH,,pH.5 pHFig.5 TheP-removalrateandstruvitecontentintheprecipitatesunderdifferentpHinpurewatersystem3 pH,pH,pH,.90%pH7.5—9.0,Ca2+90%pH7.0—7.5. Ca2+Mg2+,pH,Ca,. [1] PastorL,ManginD,BaratRetal.,APilot-scaleStudyofStruvitePrecipitationinaStirredTankReactor:ConditionsInfluencingtheProcess[J].Bioresour.Technol.,2008,99(14)∶6285—6291[2] RonteltapM,MaurerM,GujerW,StruvitePrecipitationThermodynamicsinSource-SeparatedUrine[J].WaterRes.,2007,41∶977—984[3] WilsenachJ,SchuurbiersC,VanLoosdrechtM,PhosphateandPotassiumRecoveryfromSourceSeparatedUrinethroughStruvitePrecipi-tation[J].WaterRes.,2007,41∶458—466[4] HaoXD,vanLoosdrechtMCM,Model-BasedEvaluationofStruviteRecoveryfromP-releasedSupernatantinaBNRProcess[J].WaterSci.Technol.,2006,53(3)∶191—198[5] HaoXD,WangCC,LanLetal.,StruviteFormation,AnalyticalMethodsandEffectsofpHandCa2+[J].WaterSci.Tech.,2008,58(8)∶1687—1692[6] AbbonaF,BoistelleR,LundagerH,CrystallizationofTwoMagnesiumPhosphates,StruviteandNewberyite:EffectofpHandConcentra-tion[J].J.Cryst.Growth,1982,57∶6—14[7] ,,,MAP[J].,2009,30(4)∶185—190[8] LeCorreK,Valsami-JonesE,HobbsPetal.,ImpactofCalciumonStruviteCrystalSize,ShapeandPurity[J].J.Cryst.Growth, 4:pH(MAP)763 2005,283(3—4)∶514—522[9] BanksE,ChianelliR,KorensteinR,CrystalChemistryofStruviteAnalogsoftheTypeMgMPO4.6H2O(M=Potassium(1+),Rubidium(1+),Cesium(1+),Thallium(1+),Ammonium(1+)[J].Inorg.Chem.,1975,14∶1634—1639[10] RensburgPV,MusvotoEV,WentzelMCetal.,ModellingMultipleMineralPrecipitationinAnaerobicDigesterLiquor[J].WaterResearch,2003,37(13)∶3087—3097[11] FrostRL,WeierML,KristyLErickson,ThermalDecompositionofStruviteImplicationsfortheDecompositionofKidneyStones[J].JournalofThermalAnalysisandCalorimetry,2004,76∶1025—1033[12] AltinbasM,YanginCOzturkIStruvitePrecipitationfromAnaerobicallyTreatedMunicipalandLandfillWastewaters[J].WaterScienceandTechnology,2002,46(9)∶271—278[13] AndradeA,SchuilingR,TheChemistryofStruviteCrystallization[J].MineralJournal,2001,23(5—6)∶37—46THEANALYSISANDCHARACTERIZATIONOFPRECIPITATESOBTAINEDFROMSTRUVITE(MAP)PRECIPITATIONWANGChong-chen HAOXiao-di WANGPeng LANLi(KeyLaboratoryofUrbanStormwaterSystemandWaterEnvironment,BeijingUniversityofCivilEngineeringandArchitecture,Beijing,100044,China)ABSTRACT TheprecipitatesharvestedfromMAPmethodunderdifferentpHconditionswerecharacterizedandanalyzedbyXRD,IR,TGAandelementalanalysis.TheresultsrevealthatXRDandIRcanqualitativelydeterminethepresenceofstruviteintheprecipitates,whiletheelementalanalysismethodcanquantitativelydefinetheexactcontentofstruvite.AndtheelementalanalysisresultsshowthattheoptimalpHrangeforhavinghighstruvitecontent(90.0%)wasrespectivelybetween7.5—9.0underpurewatersystemand7.0—7.5undertapwatersystem. Keywords:XRD,IR,TGA,elementanalysis,struvite.