Chlorine Ion in ConcreteMineral Ore NTIK-00112 KeM Application Note Precipitation titration byAutomatic Potentiometric Titrator Japan Concrete Institute Standard 1.Abstract Quantification of chlorine ion(Cl-)in hardened concrete is determined by potentiometrictitration using Chlorine ion electrode and Mercury sulfate reference electrode based onthe below quoted standard test methods. After 2mol/L nitric acid and 30% hydrogen peroxide solution are added to the sampleleave it to cool to room temperature, and add 0.005mol/L sodium chloride. Titrate with 0.005mol/L silver nitrate up to the endpoint, which is the maximuminflexion point on titration curve. The chlorine ion is calculated from titration volume of silver nitrate. 2.Reference 1))Japan Concrete Institute guidance JCI-SC5 Simplified Test Method for Total Salinity in Concrete 2)Japan Concrete Institute proposition JCI-SC6 Test Method for Chloride Ion inFresh Concrete by Chloride Ion SelectiveElectrode 3.Cautions in measurement Handle with care when work on chemicals.23 Use chlorine ion selective electrode, not silver electrode. . Since addition method using sodium chloride is applied, the blank level obtainedby blank test must be deducted from titration. ( 上海市漕溪路222号航天大厦北楼902室 ) 4.Post-measurement care Polish sensor element of chlorine ion electrode with supplied polishing paper (forelectrode). 5.Test equipment Main unit:Automatic potentiometric titrator (Standard preamplifier STD-) Electrode: Option Chlorine ion electrode Option Mercury sulfate reference electrode 6.Reagent Titrant : 0.005mol/L silver nitrate solution (f=1.006) Solvent : Pure water, 2mol/L nitric acid, 30% hydrogen peroxide,0.005mol/Lsodium chloride solution 7.Measurement procedure -Measurement- 1) Deliver 2.0g sample to a 200mL beaker, and add 20mL pure water to stir. 2)Add 20.0mL of 2mol/L nitric acid. 3)Add 1.0mL of 30% hydrogen peroxide solution. 4)Add 50mL pure water. 5)Cover with watch glass, heat for 10 minutes, and leave it cool to roomtemperature. 6)Add 5.0mL of 0.005mol/L sodium chloride. 7)Titrate with 0.005mol/L silver nitrate. 8)Likewise, perform blank test. 8.Formula Chlorine ion (ppm)=(EP1- BL1)×TF×C1×K1/SIZE EP1 Titration volume(mL) BL1 Blank level (5.0978 mL) FA1 Factor of titrant (1.006) C1 Concentration conversion coefficient (0.1775mg/mL) (1mL of 0.005mo1/L AgNO:=0.1775mg Cl-) K1 Coefficient(1000) SIZE Sample size (g) 京都电子工业株式会社-可睦电子(上海)商贸有限公司 ( 上海市漕溪路222号航天大厦北楼902室 ) 9.Example of measurement -Ambient condition-)一 Room temperature : 24℃ Humidity 63 % Weather : Fair -Titration parameter- -Titration curve- Model :AT-510 Method No. : 10 Titr.mode : Intermit TitrTitr.form : EP Stop [Titration parameterl Form : EP Stop APB No. :1Unit No. :1Detector No. :1Unit : nmVMax.Volume :20.0mLWait Time :20s Direction : Auto [Control parameter] End Point No. : 1 End sense : AutoEnd Point Area : OffSeparation :OffOver Titr.Vol. :0mLCut-off Time :10sUnit Volume :0.15mLDispense Speed: 55s/mLGain :5Data samp.Pot.: 4.0mVData samp.Vol.: 0.15mL
Calc.Type :SampleConc.1 :Set CO1= (EP1-BL1)*TF*C1*K1/SIZE Unit :ppmEP No. :1 Temp.Comp.: Off C1(mg/mL) :0.1775K1 :11000 Factor : 1.006 Blank1 :5.0978 *** Resu l t*** Sample No. :02-01Date:2000/06/20 16:19Method No. :10 Method Name:Intermit Titr. Blank 1 : 5.0978 Titr.Time : 00:25:20Size :2.0167g Conc-1 605.46PPm End Point-1 Uolume : 11.9358mLPotential :- 155.0mu一 250 [mU] 500. 000 32.000 [mL] (The above printout data are obtained from titration by AT510) 《Titration parameter》 Form: of titration / APB No. the burette used in titration / Unit No.: APB Unit File number Detector No.: the detector used in titration/ Unit of potential / Max Volume: of titrationWait Time: before titration starts/ Direction.:of titration《Control parameter>End Point No.: number of EPs / End sense: of EP detection / End Point Area: EP detection areaSeparation: of potential/ Dispense Speed: of dosing/Over Titr.Vol. over-titrated volume/Cut-off Time:intermittent/ Unit Volume: single dose volume /Gain: sensitivity of detection signalData samp.Pot.: potential change of sampling signal / Data samp.Vol.: titration volume of sampling signal