Use-of-Lignocellulose-Materials木质纤维素材料-as-Sorption-Media-for-Phosphorus-Removal2002

TheSocietyforengineeringPaperNumber:025001inagricultural,food,andAnASAEMeetingPresentationbiologicalsystemsUseofLignocelluloseMaterialsasSorptionMediaforPhosphorusRemovalK.G.Karthikeyan,AssistantProfessor,BiologicalSystemsEngineering,UniversityofWisconsin,460HenryMall,Madison,WI53706.kkarthikeyan@facstaff.wisc.eduMandlaA.Tshabalala,USDAForestServiceForestProductsLaboratory,OneGiffordPinchotDrive,MadisonWI53705-2398.matshabalal@wisc.eduDongmeiWang,Grad.Student,BiologicalSystemsEngineering,UniversityofWisconsin,460HenryMall,Madison,WI53706.dongmeiwang@students.wisc.eduWrittenforpresentationatthe2002ASAEAnnualInternationalMeeting/ClGRXVthWorldCongressSponsoredbyASAEandClGRHyattRegencyChicagoChicago,Illinois,USAJuly28-July31,2002Abstract.ThesuitabilityofmodifiedbarkorwoodfiberderivedfromsouthernyellowpinetofunctionasPsorbentswasinvestigated.Sorbentpreparationprocessincludedgrinding,sizefractionation]extractionforsurfaceactivation]andtreatmentwithpolyallylaminehydrochloride(PAAHCI)or3-chloro-2-hydroxypropyltrimethlyammoniumchloride.SEMimagesrevealedsurfacemorphologychangesofthesefibersduetoextractionandchemicaltreatment.Agreaterthan200%increaseinNcontentofPAA-barkcomparedtocontrol(extractedbark)togetherwiththeappearanceofastrongCIpeakintheEDXAspectraofthetreatedbarkorwoodprovidedevidenceofattachmentPAAHCItothesefibers.SurfacechargeofPAA-treatedbarkwaspositiveinthepHrange2.5-8,andturnednegativeatpHgreaterthan8.Incontrast,thesurfacechargeofuntreatedbarkremainednegativethroughoutthepHrange,2.5-9.PercentPremovaldecreasedwithincreasingPconcentration,withPAA-barkhavingahighersorptioncapacity(11.96mgP/gfiber)thanPAA-wood(7.45mgP/gfiber).Twodistinctsorptionregions,correspondingtohighandlowaffinitysites,couldbeidentifiedandthebatchdataweredescribedusingamulti-siteLangmuirmodel.Boththesorptioncapacityandbindingenergydecreasedwithincreasingionicstrength,duetocompetitionfortheavailableanionexchangesites.WeproposethatthemechanismforPsorptioninvolveselectrostaticattractionand/orspecif