饮用水中无机阴离子检测方案

IC Application Work AW CH6-0777-032003page 2/2 and UV/VIS detectionpage 3/3 Appendix IC Application Work AW CH6-0777-032003 Q Metrohm Selective determination of bromate in tap water usingpost column reaction and UVIVIS detection Branch： Water， waste water， environmental protection Keywords IC/ 762 /709/733/766/752/ Lambda 1010 /6.1005.110 / Phenomenex Star Ion A300 HC/ PCR /bromate / triiodide/ EPA 326.0/ branch 2 Summary The determination ofbromate wassdone on thePhenomenex Star lon A300 HC column using sulfuricacid / ammonium molybdate eluent and post columnreaction with potassium iodide and UV/IS detection.The limit of detection was found to be 0.05 pg/L. Sample Standards， different tap waters Reagents Eluent： 100 mM sulfuric acid + 45 pM ammoniummolybdate tetrahydrate in ultrapure water(resistivity>18 MQ) Post column reagent： 0.26 M potassium iodide (puriss. p.a.) StandardsBromate [ug/L] in ultra pure water level 1 2 3 4 5 6 7 8 BrO3 0 0.05 0.1 0.25 0.5 1 2.5 5 High ionic water standards level 9 10 11 BrOs [ug/L] 0.05 CI[mg/L] COs[mg/L] 40032 Sample Preparation n. a. Analysis The standards and samples were automatically injectedusing the 766 IC Sample Processor. Calculation Calculation was performed automatically using IC Net2.2 software based on peak area. Parameters STARTUP HARDWARE： RECORDER METHOD bromate. mt w RECORDER DATA [ch21 Lambda-1010 Range 1.000 AU Lambda nm 352.0 Ti me Co 2.000 Lamp Deuterium 752 PFump Uni t Pump on 709 IC pump Flow 1 mL/min 709IIC pum Pm n oMa 709 IC pump Pmax 7Ma START WTHINJECT： 0.0 RECORDER START START WTH DETERM NATI ON： 0. 00 Detector Lambda- 1010 Zero 766 IC Sample Processor The program： - Mve = sample - Li ft = work - Ct r l = Fi11 A Pump = 150- Crtl =Inject A Filter： Slit Gaussian 5 Sample loop： 1000 uL Results Limit of detection： [pg/L] area height BrO3 0.052 0.060 Precision： RSD [%] Standard 0.1 pg/L Standard 0.5 ug/L Standard 1.0 pg/LStandard 2.5 ug/L 9.973.38 1.640.67 Standard addition in tap water Herisau： Conc.[ug/L] Recovery Tap water Herisau +0.05 pg/L 0.1340.1880.3860.636 97.999.599.7 + 0.25 pg/L +0.50 pg/L Samples： [ug/L] BrO3 Tap water Herisau 0.134 Tap water Zurich 0.482 Tap water Stockholm 0.102 Tap water Stuttgart 1.18 Tap water Herrenberg 1.10 Tap water England I 0.063 Tap water England II 6.31 Tap water Houston < LOD Selective determination of bromate in tap water using post column reactionand UV/VIS detection QMetrohm Comments This method is designed for the selective determination ofbromate usingpost column reaction and UV/VISdetection based on the EPA method 326.0. The originalmethod uses an alkaline eluent and a PCR reagentconsisting of potassium iodide and ammoniummolybdate. lodide is oxidized by bromate in acidicmedium under catalytic influence of molybdate (VI) totriiodide (a= 352 nm). Since iodide at a low pH isunstable， the PCR reagent has to be acidified inline usingeither an anion suppressor (exchanges potassium withprotons) or the previous addition of an acid to the PCRreagent. The presentaapplication usesa highconcentrated acid eluent， which makes the inlineacidification with additional instrumentation needless. No conductivity detection can and should be used dueto the high eluent concentration. In order to avoid reaction of oxygen with iodide to triiodidethe PCR reagent and eluent should be degassed prior touse. The calculation of the limit of detection is based on teninjections of each standard plus a tenfold injection of ablank solution. The shown detection limits are averagesof three different calculation methods： The norm DIN32645， the method that is used in EPA norms and that isdescribed in “Statistik in der analytischen Chemie”(Doerffel， K.； Deutscher Verlag fur Grundstoffindustrie；Leipzig； 4. Auflage 1987； 256 pp.)， and the calculationbased on the three-fold noise. The shown detection limitscould be confirmed by chromatograms. Appendix Calibration curves and chromatograms with peak tables DateWednesday， 2003-03-12 Name Rob Proost， Applikon， Netherlands； Silke Unger， IC Marketing， Metrohm Ltd.， Herisau IC Application Work AW CH6-0777-032003 Selective determination of bromate in tap water using post column reaction Calibration curves Concentration range 0.05-5 pg/L Concentration range 0.05-1 pg/L Correlation coefficient： 0.999909 Correlation coefficient： 0.999185 6.25 E+01 Chromatograms with peak tables Standard 3： 0.25 pg/L File： n3072238 Volume： 1000 pl mn mV mV*secllVug/L7.77 0. 32 6.451 0.243 bromate IC Application Work AW CH6-0777-032003 Selective determination of bromate in tap water using post column reaction and UV/VIS detection Standard 5： 1 pg/L File： n3080304 Volume： 1000 pl 1 7.75 1. 30 27.954 1.017 bromate Limit of detection Standard 9： 0.05 ug/L in High lonic Water File： n3081140 Volume： 1000 pl 7.66 0.08 1.482 0.063 br omat e Selective determination of bromate in tap water using post column reaction Herisau tap water File： n3101105Volume： 1000 pl England II tap waterFile： n3081644Volume： 1000 ul No Ret entionmi n mV mV*sec ug/L7.70 8.30 182.948 6. 369 bromate