硫酸消解_可见光谱法快速测定化学需氧量_英文_李彦锋

收稿日期:2003-09-29基金项目:甘肃省2002年度科技攻关计划项目,污水处理新材料新工艺中试研究(GS022-A52-082);兰州大学功能有机分子化学国家重点实验室开放基金,微生物固定化及其处理有机废水的研究(SKLAOC2001-26)*通讯联系人,liyf@lzu.edu.cn硫酸消解-可见光谱法快速测定化学需氧量李彦锋*,马鹏程,周林成,易柳香,撒妮娅(兰州大学功能有机分子化学国家重点实验室,兰州大学生物化工及环境技术研究所,兰州大学化学化工学院,甘肃兰州730000)摘要:通过在442nm处测定废水样品消解后剩余Cr2O2-7的吸光度,采用计算机拟合发现当化学需氧量在65～650mg/L时,剩余Cr2O2-7的吸光度与COD浓度呈线性关系.用此法和国标法(重铬酸钾法)分别测定人工模拟废水和工业废水的COD,二者相对误差低于5.0%,表明该法具有较好的可信度和适应性,适于COD的快速准确测定.关键词:化学需氧量(COD);可见光谱法;快速测定;废水处理;计算机拟合中图分类号:O657.3;X502文献标识码:A文章编号:1004-0366(2004)01-0039-06RapidDeterminationofChemicalOxygenDemandBySulfuric-AcidDigestionandVisibleSpectrometryLIYan-feng*,MAPeng-cheng,ZHOULin-cheng,YILiu-xiang,SANi-ya(StateKeyLaboratoryofAppliedOrganicChemistry,InstituteofBiochemicalEngineering&EnvironmentalTechnology,CollegeofChemistryandChemicalEngineering,LanzhouUniversity,Lanzhou730000,China)Abstract:ArapidandsimplemethodbasedonvisiblespectrometricprocedureisproposedforthedeterminationofCODinwastewatertreatmentsystem.ItisanimprovementofstandardmethodtodetermineCOD,i.e.determinationofexcessdichromate(Cr2O2-7)byvisiblespectrometryat442nm.Theabsorbancevalue(A)ofCr2O2-7andtheconcentrationofCODhavelinearrelationbycomputeranalogy,soCODisdeterminedindirectlyinthisway.Someinfluencingfactors,suchastherefluxingtime,theamountofwastewatersampleandpotassiumdichromate,sulfuricacidconcentrationareinvestigated,respectively.TheresultshowsthatwhentheconcentrationofCODinwastewatersampleisintherangeof65～650mg·L-1,theresultsobtainedbyusingthemethodpresentedexhibitgoodagreementwiththosegivenbythestandardmethodofCODdetermination,andtherelativeerrorislessthan5.0%.Theviabilityofthismethodisdemonstratedbyanalyzingtwokindsofsyntheticwastewaterandfivekindsofindustrialwastewater,anditprovestobearapidandaccuratemethodforCODdetermination.Keywords:Chemicaloxygendemand(COD);visiblespectrometry;rapiddetermination;wastewatertreatment;computeranalogyClcMumber:O657.3;X502Documentcode:AArtcleID:1004-0366(2004)01-0039-06第16卷第1期2004年3月甘肃科学学报JournalofGansuSciencesVol.16No.1Mar.2004DO