高分辨连续光源石墨炉原子吸收光谱法测定原油中挥发性和

Amethodisproposedthatmakespossibledeterminingtotalandthermallystablevanadiumincrudeoilwithoutpriorseparation,andtocalculatevolatilevanadiumbydifference.Thevolatilefractionisbelievedtobelargelyvanadylporphyrinecomplexes.Themethodisbasedontheunsurpassedbackgroundcorrectioncapabilityofhigh-resolutioncontinuumsourcegraphitefurnaceatomicabsorptionspectrometry(HR-CSGFAAS),whichallowspyrolysistemperaturesaslowas300◦Ctobeused.Thesampleswerepreparedasoil-in-wateremulsions,andaqueousstandardsemulsifiedinthesamewaywereusedforcalibration.Totalvanadiumhasbeendeterminedusingapyrolysistemperatureof400◦C,andthermallystablevanadiumusingapyrolysistemperatureof800◦C.Thecontentoftotalvanadiumin12Braziliancrudeoilsampleswasfoundtobebetweenlessthan0.04andabout30mgkg−1.Thevolatilefractionwasbetween5and51%ofthetotalcontent,andtherewasnocorrelationbetweenthetotalandthevolatilevanadiumcontent.Thelimitsofdetectionandquantificationwere0.04and0.12mgkg−1ofVincrudeoil,respectively,basedonamassof2gofoilin10mLofemulsion.Theprecisionwasbetterthan4%atthe3mgkg−1levelandbetterthan1.5%atthe30mgkg−1levelofVincrudeoil. contrAA®700连续光源 火焰/石墨炉原子吸收光谱仪