Method for Chloride Determination by Ferric Thiocyanate, Version 2.0

Transcription

1 Methd fr Chlride Determinatin by Ferric Thicyanate, Versin 2.0 PRINCIPLE This methd is designed fr the determinatin f chlride in water, sil, and ther frms f samples. The sample is prepared ffline if necessary and then intrduced t the FIAlab analyzer. When chlride is mixed with mercuric (II) thicyanate, it cmplexes with Hg(II). The thicyanate that is released cmbines with Fe(III) ins present in the reagent t frm ferric thicyanate, which can be measured spectrphtmetrically. This methd is designed t be run n the FIAlyzer-1000 r FIAlyzer-FLEX. SUMMARY This methd is designed fr the determinatin f chlride in water, sil, and ther frms f samples. The methd is capable f detecting chlride in the range f mg Cl/L. Fr mre infrmatin, see the sectin n perfrmance metrics. COMPLIANCE The methd fllws Standard Methd 4500-Cl- E., 4500-Cl- G. SAFETY The txicity r carcingenicity f all reagents used in this methd must be taken int accunt and therefre each chemical listed belw shuld be handled accrdingly. Each labratry is respnsible fr maintaining cmpliance with OSHA regulatins regarding the safe handling f the chemicals specified in this methd. Material Safety Data Sheets (MSDS) shuld be made available t all persnnel using the methd. All waste materials shuld be dispsed f in a respnsible manner, in accrdance with federal, state, lcal, and any ther applicable regulatins. The fllwing chemicals have the ptential t be highly txic r highly hazardus; fr detailed explanatins cnsult the MSDS: Mercuric Thicyanate Methanl Page 1

2 EQUIPMENT AND SUPPLIES Equipment: Balance, analytical, with a 0.01 g reslutin Pipettes fr making standards Glassware: Class A vlumetric flask, 1L, QTY 2 Graduated cylinder, 100mL, QTY 1 Glass strage cntainer, 1L, clear, QTY 2 Autsampler (fr high sample lads): Cetac ASX-280/560 (recmmended) r AIM-3200/3300 Page 2

3 REAGENTS AND STANDARDS Chemical part numbers refer t Fisher Scientific unless nted therwise. Chemical Chem. Frmula CAS# Supplier PN Deinized Water H 2O Mercuric thicyanate slutin g/l in methanl. Ferric nitrate slutin. 202 g/l in 0.4M nitric acid Preparatin f Reagents Carrier: Matrix match carrier t samples. Salt slutin t seawater samples, extractin slutin fr sil samples, etc. Reagent 1: Chlride reagent (1 L) Add 150mL f mercuric thicyanate slutin and 150mL f ferric nitrate slutin t 600mL f DI water. Add deinized water t a ttal vlume f 1L. Mix well and stre in a glass bttle. The reagent shuld be a light range clr with n particles in it. Prbe Wash Slutin: Water with 0.1% Brij L23 (1L) Add 3.3mL Brij L23 t 800mL f deinized water, dilute t 1L. Mix well and stre in a glass bttle. The wash slutin shuld be clear with n particles in it. Ntes n reagent shelf life: Use f high quality labratry glass bttles is imprtant. Reagent 1 shuld be prepared every 4 weeks. Preparatin f Standards Dilute 1000 mg/l Cl - stck slutin with carrier t the desired range f chlride standards. SAMPLE COLLECTION AND PRETREATMENT This prtcl nly cvers the analysis prcess. Sample cllectin and pretreatment depends n the type f sample and will have t be determined separately. Page 3

4 INSTRUMENT SETUP MID-RANGE Flw injectin analysis apparatus parameters: Cmpnent Specificatins FIAlab PN Analyzer FIAlyzer-1000 r FIAlyzer-FLEX flw injectin analyzer *Inquire Spectrmeter FLAME-T-VIS-NIR Spectrmeter nm Light surce HL-2000-LL, tungsten-halgen, nm SMA-Z flw cell Light path 10mm Peristaltic pump tubing 1.02mm/0.04in ID (white/white) *Inquire Peristaltic pump tubing 0.76mm/0.03in ID (black/black) *Inquire Sample injectin lp 105µL 9.0in/23.0cm f Tefln capillary tubing with in/0.71 mm ID Reactin cil 1 750µL in/165cm f Tefln capillary tubing with 0.03 in/0.75 mm ID SOFTWARE PARAMETERS: Parameter Value Pump Speed 30% Primary Spectrmeter Wavelength 480nm Reference Wavelength 650nm Fig. 1- Flw schematic fr chlride determinatin. Page 4

5 FIASOFT METHOD The prgram script using an autsampler is shwn belw. Fr manual sample intrductin see the FIAsft manual. 'Chlride methd script. FIAlab Injectin Valve Sample Lad FIAlab Peristaltic Pump CunterClckwise(%) 30 Autsampler Wash Next Sample Delay (sec) 60 Lp Start Autsampler Wash Analyte New Sample Next Sample FIAlab Injectin Valve Sample Inject Delay (sec) 3 FIAlab Injectin Valve Sample Lad Spectrmeter Reference Scan Spectrmeter Absrbance Scanning Delay (sec) 30 Spectrmeter Stp Scanning Lp End Autsampler Rinse Delay (sec) 60 Autsampler Wash Delay (sec) 30 Autsave Data C:\Users\FIAlab\Desktp\Autsave Data\DateTime FIAlab Peristaltic Pump Off Page 5

6 PERFORMANCE METRICS Fig. 2 Example plt and calibratin data fr chlride. Page 6

7 Lwer limit f detectin: 0.2mg Cl/L 5.6*10-6 ml/l Lwer limit f quantificatin: 0.5mg Cl/L 14*10-6 ml/l Upper limit f detectin: 20mg Cl/L 0.56*10-3 ml/l Sample thrughput: 90 samples / hur Startup + Calibratin: 5 minutes Shutdwn: 5 minutes Nte: due t the range clr f R1, using an ptical path f lnger than 10mm is nt feasible. Page 7