Assessment of enhanced nitrite removal and monito

ContentslistsavailableatScienceDirectChemicalEngineeringJournaljournalhomepage:www.elsevier.com/locate/cejAssessmentofenhancednitriteremovalandmonitoringusingligandmodifiedstableconjugatematerialsMd.RabiulAwuala,b,c,⁎,AbdullahM.Asirib,MohammedM.Rahmanb,NabeelH.AlharthicaDepartmentofChemicalEngineering,CurtinUniversity,GPOBoxU1987,Perth,WA6845,AustraliabCenterofExcellenceforAdvancedMaterialsResearch,FacultyofScience,KingAbdulazizUniversity,Jeddah21589,SaudiArabiacMechanicalEngineeringDepartment,CollegeofEngineering,KingSaudUniversity,Riyadh11421,SaudiArabiaHIGHLIGHTS•Conjugatematerialwasfabricatedforenhancedcapturingofnitrite(NO2−)ions.•ThematerialisabletoeffectivelyNO2−capturinginthepresenceofforeignions.•ThesolutionpH5.50waseffectiveforselectivemonitoringandremovalop-erations.•Theconjugatematerialswereex-hibitedthehighremovalcapacityof119.22mg/g.GRAPHICALABSTRACTARTICLEINFOKeywords:Toxicnitrite(NO2−)ConjugatematerialsCapturingHighremovalefficiencyMulti-cyclereusesABSTRACTInthisstudy,stableconjugatematerialwasfabricatedbyfunctionalorganicligandembeddedontotheporoussilicaforefficientdetectionandadsorptionoftoxicnitrite(NO2−)ionsfromcontaminatedwater.ThedetectionmethodwasobviouslydetectedtheNO2−ionsevenintheultra-traceamountwithsignificantcolorformation.Severalexperimentalframeworks,includingpHeffect,reactiontime,lowlimitdetection,competingionseffect,maximumremovalcapacityandreuseswereinvestigatedsystematicallybothinthedetectionandremovaloperations.Thelowlimitofdetectionwas0.16µg/L,whichwascompiledthehigh-sensitivitydetectionoftheNO2−ions.ThesolutionpHwasdisplayedakeyfactor,anditwasoptimizedcarefully.TheoptimumpHwas5.50bothinthedetectionandadsorptionmodeinthisstudy.Thecontacttimeshowedthatthekineticsper-formancewasslowcomparedwithpreviousseveralnanomaterials.ThiswaspostulatedthattheNO2−ionsremovedasmonovalentandconsistedinwastewaterasanions.TheadsorptiontrendwashighlycompetentaccordingtoLangmuirisotherms,andthehighestremovalcapacitywas119.22mg/gbytheconjugatematerials