Hanna Instruments HI 4102 User manual

1
HI 4002HI 4002
HI 4002HI 4002
HI 4002
HI 4102HI 4102
HI 4102HI 4102
HI 4102
Bromide Ion
SelectiveElectrode
Instruction Manual
Half-cell
Combination
BROMIDE
HI 4002
HI 4102
BROMIDE
COMBINATION

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HI4002BromideHalf-cellHI4002BromideHalf-cell
HI4002BromideHalf-cellHI4002BromideHalf-cell
HI4002BromideHalf-cell
HI 4102 Bromide Combination ElectrodeHI 4102 Bromide Combination Electrode
HI 4102 Bromide Combination ElectrodeHI 4102 Bromide Combination Electrode
HI 4102 Bromide Combination Electrode
I.I.
I.I.
I. Introduction:Introduction:
Introduction:Introduction:
Introduction:
The Hanna HI 4002and HI 4102 are ion selective elec-
trodes designed for the measurement of Bromide ions in
aqueous solutions. The HI 4002 is a solid state half-cell
sensorthatrequiresaseparatereference.TheHI4102isa
combinationionselectiveelectrode.
IIII
IIII
II. SpecificationsSpecifications
SpecificationsSpecifications
Specifications
Type: SolidStateelectrodewith
aSilverBromidepellet.
Ion(s)measured: Bromide(Br--
--
- )
Measurementrange: 1.0Mto1X10-6M
79,910to0.08ppm
Interferingions: Cyanide, and Mercury
mustbeabsent.Ratioof
interferingiontoBr--
--
-must
belessthantheratio
indicated below:
0.01 forI--
--
-iodide
0.01 forCN--
--
-cyanide
50 forCl--
--
-Chloride
Operating Temperature: 0-80°C
Operating pH: 2-12.5pH
Dimensions: 12 mm (OD) X 120 mm
nominal insertion
(0.47”X4.72”)
Connection: BNC

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III.III.
III.III.
III. Theory of OperationTheory of Operation
Theory of OperationTheory of Operation
Theory of Operation:::::
TheHI4002orHI4102Bromideelectrodesarepotentio-
metricdevicesusedfortherapiddeterminationoffreeBro-
mideionsinfoodproducts,beverages,plants,soilsandas
anindicatorintitrations.Theelectrodefunctionsasasen-
sor or ionic conductor. The HI 4002 requires a separate
referenceelectrodetocompleteitselectrolyticcircuit. The
HI4102incorporates areferenceelectrode.ThesilverBro-
mide pellet is practically insoluble in the test solutions
being measured and produces a potential change due to
changesinthesample’sionactivity.Whentheionicstrength
ofthesampleisfixedbytheadditionofISA,thevoltageis
proportionalto theconcentration ofbromide ionsinsolu-
tionandtheelectrodefollowstheNernstequation.
E=Ea +2.3RT/nFlogAion
E=observedpotential
Ea=Referenceandfixedinternal voltages
R=gasconstant(8.314J/KMol)
n= Chargeonion(1-)
A i=ion activity in sample
T=absolutetemperature inK
F=Faradayconstant(9.648x104C/equivalent)

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IV.IV.
IV.IV.
IV. Design elements of the HI 4002 and HI 4102Design elements of the HI 4002 and HI 4102
Design elements of the HI 4002 and HI 4102Design elements of the HI 4002 and HI 4102
Design elements of the HI 4002 and HI 4102
electrodeselectrodes
electrodeselectrodes
electrodes
BROMIDE
HI 4002
Cap
Sensing
Membrane
Sensor
Handle
UpperCap
Spring
O-Ring
CeramicJunction
onInnerStem
FillHole
O-Ringand
Plug
Sensing
Membrane
OuterSleeve
Upper
Threads
Liquidjunction

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V.V.
V.V.
V. Equipment required:Equipment required:
Equipment required:Equipment required:
Equipment required:
•HannaHI5315DoubleJunctionReferenceElectrode
withHI7072FillSolutionforHI4002.
•Hanna HI 4222 pH/ISE/mV meter or other suitable
ionorpH/mVmeter.(Note:log/lineargraphpaperis
usefulifan ISE(ion) meteris notavailable).
•HannaHI180MagneticStirrerorequivalentwithTFE
coatedstirringbars(HI731320). Note:isolatebea-
kers from stirrer motor heat by placing insulating
materialsuchasfoamorcorkbetweenthem.
•HannaHI76404ElectrodeHolderorequivalent.
•Plasticbeakers(HI740036P)orothersuitablemea-
surementvessel.
VI.VI.
VI.VI.
VI. Solutions RequiredSolutions Required
Solutions RequiredSolutions Required
Solutions Required for Bromide Measurementsfor Bromide Measurements
for Bromide Measurementsfor Bromide Measurements
for Bromide Measurements
0.1M BromideStandard,500mL HI4002-01
ISA,500mL HI4000-00
ForMolarsolutions:
Usingvolumetricpipettesandglasswaremakeserialdilu-
tions to approximately bracket the concentration of the
samples. Standardswithconcentrations <10-3Mshould
be prepared daily.
TwomLofHannaISAforHalideelectrodes (HI4000-00)
shouldbe addedto 100mLof sampleorstandard.
Forppmsolutions:
Prepare 799 ppm bromide standard by diluting HI4002-
01:Pipette100mL standardtoa 1litervolumetric flask.
Adddeionizedwatertovolume.Usingadditionalvolumet-
ricpipettesandglasswaremakeserialdilutionsofthis799
ppm standard to approximately bracket the concentration
ofthesamples. Standardswithconcentrations<80ppm
should be prepared daily.
TwomLofHannaISAforHalideelectrodes (HI4000-00)
shouldbe addedto 100mLof sampleorstandard.

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VIIVII
VIIVII
VII. General GuidelinesGeneral Guidelines
General GuidelinesGeneral Guidelines
General Guidelines
•Calibration standards and sample solutions should
havethesameionicstrength.ISAshouldbeaddedto
bothsamplesandstandardsinthesameratio.1part
ISAto50partsstandardisthenormaldosing.
•Concentrated samples (>1 M) should be diluted
beforemeasurement. Multiplythefinalresultbythe
correspondingdilutionfactor.
•For high ionic strength samples, prepare standards
with similar ionic strength by increasing the ISA
addiiton.
•Calibration standards and sample solutions should
beatsametemperature.
•The magnetic stirrer may generate heat. Thermally
insulate beaker containing standard or sample from
magnetic stirrer by placing cork or other insulative
sheetbetweenbeakerandstirrerplate.
•Calibration standards and sample solutions should
be stirred at the same rate using identical sized TFE
coatedstirbars.
•Rinseelectrodepairwithdistilledordeionizedwater
between samples and gently dab dry with soft dis-
posableabsorbenttoweling.Donotrubelectrodes.
•Presoaking bromide sensor in a dilute standard will
optimizeresponse.Useconcentrationsapproximately
10-3Morless.
•A scratched, pitted, or tarnished pellet surface can
causedrift,alossoflowlevelresponse,orpoorrepeat-
ability. Optimumresponsecanberestoredbyremov-
ingthedamagedsurfacewiththemicroabrasivestrip
HI4000-70.
•Avoidlargechanges intemperature (thermalshock)
asit maydamagethesensor.
•Gasbubblesmayformfromsolutionout-gassingdue
totemperaturechange. Gentlytapbodyofsensorto
dislodgethem frommembranesurface.

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HI4002
•Removeprotectivecoverfromsensortip.
•PrepareHI5315referenceelectrodebyfillingelectro-
lytereservoirwithHI7072fillsolution.
•Place sensor and reference electrodes into electrode
holderandconnectcableconnectorstometer.
HI4102
•Remove the protective plastic wrap that covers the
ceramicjunctionbeforeassemblingsensorforthefirst
time.
•HI7072referencefillsolutionshouldbeaddeddaily
toelectrolytereserviorbeforeelectrodeuse.
•During measurement always operate electrode with
thefillholeopen.
•Duringnormal use,fill solutionwillslowlydrainout
ofthetaperedconejunctionatthelowerportionofthe
electrode.Excessiveloss(>4cmdropwithin24hours)
isnotnormal.Ifthisoccursverifycapistightenedand
the interface between the internal cone and outer
bodyisfreeofdebris.
•Addfillsolutiondailytomaintainagoodheadpres-
sure.Foroptimumresponse,thislevelshouldbemain-
tainedandnotbeallowedtodropmorethan2-3cm
(1-inch) below fill hole. It must cover the ceramic
foundontheinnerstem.
•Ifanerraticmeasurementoccurs,checktoseeiffor-
eign matter is seen trapped near the internal cone.
Drainand refillwith freshfill solution.

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VIII.VIII.
VIII.VIII.
VIII. Electrode PreparationElectrode Preparation
Electrode PreparationElectrode Preparation
Electrode Preparation
HI4002
1. Removeprotectivecoverfromsensortip.
2. Preparereferenceelectrodebyfillingouterelectrolyte
reservoirwithHI7072.
3. Place sensor and reference electrodes into electrode
holderandconnectcableconnectorstometer.
HI4102
1. Unwrapplasticfilmsealfoundoverceramicjunction
oninnerstemanddiscard.Thisisonlyusedforship-
ping and long term storage.
2. Rinseinnerstemwithdeionizedwatermakingcertain
towettheo-ringfoundontheinnerstem.
3. Reassemble electrode by gently pushing the inner
assembly into the outer body, sliding spring down
cable, and screwing cap into place.
4. Removefillholecoverando-ringonfillholespout.
5. Usingthedropperpipetteprovided,addafew drops
HI7072fillsolutionto theelectrode,wetting theo-
ring and rinsing out the fill solution chamber.
Deionized
Water
Remove
Parafilm

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6. Holdingthebodyoftheelectrodegentlypress upper
capwithyourthumb.Thispermitsthefillsolutionto
drain out of the body. Release cap and verify elec-
trodereturnstoitsoriginalposition.(Youmayneedto
gentlyassistforthistooccur).
7. Tightentheelectrodecapontothebodyandfillelec-
trodebodyuntilfillsolutionvolume isjustbelowfill
hole.
8. Position electrode in a Hanna HI 76404 electrode
holder (orequivalent)andconnect plugto meter.
HI 4102
BROMIDE
COMBINATION

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IX.IX.
IX.IX.
IX. Quick Check of Electrode SlopeQuick Check of Electrode Slope
Quick Check of Electrode SlopeQuick Check of Electrode Slope
Quick Check of Electrode Slope
•ConnectsensorstopH/mV/ISEmeter
•PlacemeterinmVmode.
•Place100mLofDIWintoabeakerwithstirbar.
•Placeelectrodesintopreparedsample.
•Add 1 mL of a standard (0.1 M or 1000 ppm stan-
dard)tobeaker.RecordthemVvaluewhenstable.
•Addanadditional10mLofstandardtothesolution.
Record the mV when reading has stabilized. This
value should be less than the previous noted (more
negative).
•DeterminethedifferencebetweenthetwomVvalues.
Anacceptablevalueforthisslopeis-56±4mV.
X.X.
X.X.
X. Corrective actionCorrective action
Corrective actionCorrective action
Corrective action
•Verifyprotectivecaphasbeenremoved(HI4002).
•Verifyplasticfilmhasbeenremovedfrominnerstem
(HI4102).
•Verifyelectrodesareconnectedproperlytometerand
meterispowered.
•Verify dilute standards are freshly made and stored.
Remakesolutionsifappropriate.
•If the sensor slope just misses the suggested slope
window,soakingthesensorinadilutestandardmay
solvethe problem.(<10-3Mbromide or <80ppm
standard).
•A scratched sensing surface can be polished with HI
4000-70 polishing strip. Cut off approximately 1
inchofthemicro-abrasivestrip.Wetthefrostedside
with deionized water and place against damaged
membraneoftheelectrode. Placeyourthumbagainst
the shiny backing and slowly rotate back and forth
while applying gentle pressure. Continue polishing
untilyouaresatisfiedwiththesurface. Ifdarkdepos-
itsappearon polishingstrip movethepaperslightly
and continue polishing.

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•Ifthemembraneisdamaged,theresponsebecomes
extremelysluggish, orthe slopeof theelectrodehas
decreased significantly, and procedures above have
nothelped,thesensor shouldbereplaced.
XI.XI.
XI.XI.
XI. Direct Calibration and MeasurementDirect Calibration and Measurement
Direct Calibration and MeasurementDirect Calibration and Measurement
Direct Calibration and Measurement
This method is a simple procedure for measuring many
samples. A direct reading ISE meter (HI 4222 or equiva-
lent)determinesconcentrationoftheunknownbyadirect
readingaftercalibratingthemeterwiththestandards.The
meter is calibrated with two or more freshly made stan-
dards that are in the linear measurement range of the
unknowns. Morecalibrationstandardsarerequiredinnon-
linear regions. Unknowns are read directly. At very low
levels of bromide, special precautions must be employed
forreproduciblemeasurements. Waterusedforstandards
mustbebromidefree andsensorsandglasswaremust be
rinsedrepeatedlywith thiswater toprevent carry over.In
the region where the electrode response appears curved,
more calibration points are needed, and calibration will
needtoberepeatedmorefrequently.
A pH/mV meter in mV mode with semi log graph paper
mayalsobeused. Twoormorefreshlypreparedstandards
that are in the measurement range of the unknowns are
measuredinmVmodeonthemeter.
These values are plotted on the semi-log paper and the
points are connected to form a straight-line curve. When
samples are measured, their mV values are converted to
concentrationbyfollowingthemVtotheconcentrationaxis
onthesemi-logplot.

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Procedure
1) Follow sections VIII and IX to prepare sensors for
measurement.
2) Follow sectionVItopreparestandards/solution. Stan-
dards should bracket and fall within the range of
interest.
TwomLHI4000-00ISA,isaddedto100mLofboth
samples and standards Add stir bar and mix before
taking measurements.
3) Follow sectionVII;GeneralGuidelinestooptimizetest
set-up.
4) Duringcalibrationitisbesttostartwithlowerconcen-
trationsamplesfirst. Waitforastablemeasurement
before recording values. Slightly longer equilibra-
tionsarerequiredatlowerconcentrations.
5) Topreventcarryoverandcontaminationofsamples,
rinsesensorswithDIWanddapdrybetweensamples.
Typical Linearity for HI 4002 and HI 4102 Bromide
sensors
-150
-100
-50
0
50
100
150
200
01234567
-Log of Molar Concentration
mV

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XII.XII.
XII.XII.
XII. Other Measurement TOther Measurement T
Other Measurement TOther Measurement T
Other Measurement Techniquesechniques
echniquesechniques
echniques
KnownAddition (forBr-)
Anunknownconcentrationcanbedeterminedbyaddinga
known amount (volume and concentration) of measured
ion to a known volume of the sample. This technique is
called Known Addition. The method can use an ideal
sensorslope,butactualdeterminedslopesatthetempera-
tureofmeasurementshouldbeusedifknown. Thevolume
andconcentrationoftheaddedstandardmustcauseamV
changeofatleast30mV.Thismethodispreprogrammed
intheHannaHI4222pH/ISE/mVmeter,whichsimplifies
themethod greatly.
Example:Bromideiondeterminationwithknownaddition.
1. A50 mLsampleof unknown(Vsample) isplacedin
aclean plasticbeaker withabromide sensor.Add 2
mLof HI4000-00ISA(VISA),mixwellandrecordthe
stable mV value (mV 1).
2. 5mL(Vstd)of10-1M(Cstd)standardisaddedtothe
beaker and the mV value decreases. The unknown
bromide concentration in the original sample
(Csample) can then be determined by the following
equation.
3. The procedure can be repeated with a second stan-
dard addition to verify slope and operation of the
method.
C
sample
=(V
T
)10
∆E/S
- (V
S’
)
C
standard
V
standard
V
sample
V
S’
(V
sample
+V
standard
+V
ISA
)= V
T
(V
sample
+V
ISA
)= V
S’

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Abromideelectrodemaybeusedasanindicatortofollow
theprogress ofa bromidetiration withsilver nitrate. The
electrode can be used in colored samples where other
indicatorssufferfrominterferences.Duringthetitrationthe
sensorfollowsthedecreaseinbromideconcentrationwhile
smalladditionsofsilvernitatetitrantareadded.Thesilver
reactswiththebromideionsformingaprecipitateof silver
bromide. Atthestoichiometricendpoint,alargechange
inmVoccurs. Measurementsmaybeautomatedbyuseof
theHannaTitratorHI901ortitratedmanually.
XIII.XIII.
XIII.XIII.
XIII.pHpH
pHpH
pH
The HI 4102 and HI 4002 electrodes may be used in
solutions with pH values between 2 and 12.5. Samples
that fall beyond this range should be adjusted.
TitrationTitration
TitrationTitration
Titration
XIV. SXIV. S
XIV. SXIV. S
XIV. Storage and Care of the HI 4002 andtorage and Care of the HI 4002 and
torage and Care of the HI 4002 andtorage and Care of the HI 4002 and
torage and Care of the HI 4002 and
HI 4102 sensorsHI 4102 sensors
HI 4102 sensorsHI 4102 sensors
HI 4102 sensors
TheHI4002sensorcanbestoredinverydilutestandards
(<10-3M) for short periods of time and should be stored
drywiththeprotectivecaponwhennotinuse.
The model HI 4102 combination electrode can be left in
dilutestandards(<10-3 M)forshorttimeperiods.
Forlongtermstorage,theelectrodeshouldbedrainedand
washedofsaltswithdistilledotdeionizedwater.Unscrew
theuppercapand moveoutersleeveupcable. Wrap the
ceramicjunctionontheinnerstemwithParafilm®orother
sealing wrap. Place the protective cap provided over the
sensor membrane. Store dry disassembled electrode in
storageboxprovidedwithelectrode.

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XVXV
XVXV
XV..
..
. Conversion TConversion T
Conversion TConversion T
Conversion Tablesables
ablesables
ables
For BrFor Br
For BrFor Br
For Br--
--
-MultiplybyMultiplyby
MultiplybyMultiplyby
Multiplyby
Moles/L(M)toppm(mg/L) 7.99x104
ppm(mg/L)toM(moles/L) 1.252x10-5

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MAN4102 11/07
WARRANTYWARRANTY
WARRANTYWARRANTY
WARRANTY
HannaInstrumentsIonSelectiveElectrodesarewarranted
to be free of defects in material and workmanship for 6
monthsfromdateofpurchasewhenusedfortheirintended
purposeandmaintained accordingtoinstructions. Ifthey
failtoworkwhenfirstusedcontactyourdealerimmediately.
Damageduetoaccidents,misuse,misapplication,tampering
orlackofprescribedmaintenanceisnotcovered.
HannaInstrumentsreservestherighttomodifythedesign,
constructionorappearanceofitsproductswithoutadvance
notice.