简介:Magneticreducedgrapheneoxide(MRGO)nanocompositewaspreparedbythechemicalcoprecipitationmethodandappliedasadsorbentforremovingemulsifiedoilfromoilywastewater.SEM,TEM,XRD,FT-IR,VSMandotheranalyticalmethodswereutilizedtocharacterizethepreparedMRGO.TheadsorptionperformanceofMRGOwasevaluatedunderdifferentinitialadsorbateconcentration,MRGOdosage,temperature,andpHvalueofthesolution.Theadsorptionkineticsandisothermswereinvestigated.Inaddition,theMRGOrepeatabilitywasalsotested.Itwasfoundthatalmost65%ofemulsifiedoilwereremovedbyMRGOinthefirst15min.TheMRGOadsorptioncapacityandefficiencyforremovalofadsorbatereached335.85mg/gand92.52%within60min,respectively.TheadsorptioncapacityreducedwithanincreasingMRGOdosage,whileincreasedwiththeincreaseofemulsifiedoilconcentration.TheadsorptionperformanceofMRGOinthealkalineenvironmentwaslowerthanthatintheacidicenvironment.Theadsorptiondatacouldwellfittothepseudosecond-ordermodel.TheLangmuirmodelcouldwelldescribetheisothermdata.TheMRGOadsorptioncapacitywasstillmorethan236.1mg/gatthesixthregenerationcycle.
简介:Inthisstudy,themainfactorsinfluencingthemeasurementsbymeansoftheoff-linelow-field1HNMRinthelabwerediscussedbaseonarobustcalibrationmodelestablishedbythePLSalgorithmusing255crudeoilsamples.Thepreheatingtemperaturehadagreatinfluenceontheviscosityofoilsamplesandtheresolutionofspectralanalysis.Therepeatabilityofspectralmeasurementswasimpactedbythemetalandwaxcontentoftheoilsamples.Forthecaseofhighwaxcontentoils,thewaxspeciesbegantocrystallizeinthecourseofdeterminationthatcouldaffecttherepeatabilityofspectralmeasurements.ThesefactorshaveevidencedwhythepreheatingdevicesandfilterunitarenecessarywhenlowfieldNMRsystemisusedintheonlineanalysisprocess.Theinvestigationisveryimportantfortheon-lineapplicationofthelowfieldNMR.