INSTRUCTION MANUAL HI 901 / HI 902 AUTOMATIC TITRATOR 2003 Nov 12, 15:44:31 rant NaOH Tit 0. 000 Conc. N (eq/L) 0 RPM 1300/130 No Result Standard NaOH 0.
TABLE OF CONTENTS Chapter 1. INTRODUCTION Chapter 2. SETUP Chapter 3. USER INTERFACE Chapter 4. GENERAL OPTIONS Chapter 5. METHODS Chapter 6. TITRATION MODE Chapter 7. pH & mV MODE Chapter 8. AUXILIARY FUNCTIONS Chapter 9. MAINTENANCE, PERIPHERALS Appendix 1. TECHNICAL SPECIFICATIONS Appendix 2. BACK TITRATION (HI 902 only) Appendix 3. MULTIPLE EQUIVALENCE POINTS (HI 902 only) Appendix 4.
Dear customer, Thank you for choosing a Hanna Instruments Product. This instruction manual has been written for the HI 901 / HI 902 Titrator products. Please read this instruction manual carefully before using the instrument. This manual will provide you with the necessary information for the correct use of the instrument. © 2004 Hanna Instruments All rights are reserved. Reproduction in whole or in part is prohibited without the written consent of the copyright owner, Hanna Instruments Inc.
INTRODUCTION 1 INTRODUCTION HI 901 and HI 902 are automatic titrators with high accuracy, great flexibility and repeatability. The titrators are designed to perform a variety of potentiometric titrations, allowing the user to obtain both good results and high speed analysis. The main attributes of these titrators are: Flexibility Support up to 100 titration methods (standard and user defined). High accuracy Precise dosing system (under 0.1% accuracy). Precise mV and pH measurements (± 0.1 mV and ± 0.
INTRODUCTION 1-2
SETUP Chapter 2. Contents 2 SETUP ................................................................................................... 2 - 3 2.1 Unpacking ............................................................................................. 2 - 3 2.2 Safety Measures ................................................................................... 2 - 4 2.3 Installation ........................................................................................... 2 - 5 2.3.
SETUP 2-2
SETUP 2 SETUP 2.1 Unpacking The titrator and the accessories are shipped in a single box containing: 1 2 3 4 5 6 9 10 11 12 13 14 15 16 ITEM QUANTITY Titrator............................................................................... 1 Pump Assembly.................................................................. 1 Burette Assembly.................................................................
SETUP 2.2 Safety Measures The following safety measures must be followed: 1. Always ensure that the power-supply cable is connected to a grounded main power plug. 2. Never connect or disconnect the pump assembly with the titrator turned on. 3. Verify that the burette and the attached tubing are as described in this manual (see 9.1 Burette Maintenance section for more details). 4. Always check that the titrant bottle and the titration beaker are firmly sitting on a flat surface. 5.
SETUP 2.3 Installation 2.3.1 Titrator Front View NaOH 0.1 M 2.3.
SETUP 2.3.3 Titrator Left-side View 2.3.4 Titrator Assembly Note: Assembly operations must be completed before connecting the titrator to the power-supply voltage! 2.3.4.1 Assembling Stirrer Stand and Support Follow these steps to assemble the stirrer: Remove the screws (2) from the titrator chassis (1). Attach the stirrer stand (3) to the titrator chassis. Make sure to position the stirrer stand close to the wall of the chassis.
SETUP 2.3.4.2 Attaching Stirrer To attach the stirrer to titrator, follow these steps: Attach the propeller (2) to the stirrer (1) by pressing it onto the stirrer shaft. Insert the pH electrode (3) and temperature sensor (4) into the dedicated holes on the stirrer. Push them in until they are tightened in a stable position. Slide the stirrer on the stirrer support and set the height by tightening the screw located on the positioning collar (5).
SETUP 2.3.4.3 Connecting the Pump To connect the pump, follow these steps: Retrieve the pump cable from inside the bay. The pump 1 connector is located in the left side bay. Connect the cable to the pump as shown in the figure below. The pump connector is located in the lower part of the pump, near the motor. Insert the pump (2) into the dedicated bay. Lower the pump until it reaches the lowest position, then slide it towards the front of the titrator chassis (1) until it is firmly latched.
SETUP HI 902 only: Follow the previous steps (2.3.4.3) to connect and attach the second pump. 2.3.4.4 Attaching Burette Blank Support (HI 901 only) The burette blank support installation procedure is as follows: Insert burette blank support (4) in the dedicated bay - on the right side (see the previous picture). Lower the burette blank support until it reaches the lowest position, then push it toward the front of the titrator chassis (1) until it is firmly latched.
SETUP 2.3.4.6 Electrical Connections Connect the pH electrode to the BNC connector (5). Connect the temperature sensor to the RCA connector (6). Connect the stirrer to the MINI-DIN connector (7). Connect the power-supply cable to the power supply connector (2).
SETUP 2.3.5 Connection to Earth It is important that the titrator has a good connection to Earth. The titrator is properly grounded through the power cord and for added confidence the unit can be connected to Earth using the optional 5 mm screw and the nut connection located on the rear panel of titrator. Connect to Earth (optional) 2.3.6 Floppy Disk Drive Report files, new created (user) methods, standard methods can be transferred to and from the titrator using a standard 3.5 floppy disk.
SETUP 2-12
USER INTERFACE Chapter 3. Contents 3 USER INTERFACE .................................................................................. 3 - 3 3.1 Start Up .................................................................................................3 - 3 3.2 Description ............................................................................................ 3 - 4 3.2.1 Keypad .................................................................................................... 3 - 4 3.2.1.
USER INTERFACE 3-2
USER INTERFACE 3 USER INTERFACE 3.1 Start Up Once the instrument is assembled and installed, please follow these steps to start up the titrator: Connect the instrument to a main power plug with ground wire. Make sure that the voltage of the main power and the one specified on the titrator are the same. Turn on the titrator from the power switch located on the back of the instrument. Wait until the titrator finishes the initialization process.
USER INTERFACE 3.2 Description This chapter describes the basic principles of navigating through the user interface, selecting fields and entering values from the keypad. 3.2.1 Keypad The titrators keypad is grouped into four categories, as follows: 3.2.1.1 Function Keys If one of these keys is pressed, the associated function is immediately performed.
USER INTERFACE 3.2.1.3 Arrow Keys These keys have the following functions: Move the on-screen cursor. Increase and decrease the stirrer speed and other settings. In the alphanumeric screen, to select a letter or to navigate through menu options. 3.2.1.4 Numeric Keys Keys to - Used for numeric entries. - Toggles between positive and negative values. - Decimal point. - Initiates entry of exponent for scientific notation. 3.2.1.
USER INTERFACE The user interface contains several screens. For each titrator function, one or more screens are used. Warnings and other critical information are displayed in reversed font. 3.2.3 The Main Screen After start up and initialization, the first screen displayed is the main screen.
USER INTERFACE 3.3 Menu navigation 3.3.1 Selecting an Option To select an option, simply press the option key below the virtual option key. For example, to access the Method . Options screen press 3.3.2 Selecting a Menu Item To select an item from the menu screen use the arrow keys and to move the cursor. When the menu is larger than the display, a scroll bar is active on the right side. The and keys can be used to scroll through the pages. or . To activate the selected menu item, press 3.3.
USER INTERFACE 3.3.4 Saving Modifications The Saving Method screen allows the user to save the modifications. To exit from Saving Method screen without saving, press or highlight the Exit Without Saving Method option and then press . To save the modifications highlight the Save Method option and then press . After the method name is changed, it appears in the method name field. Note: To access the contextual help menu, press displayed screen. Press 3-8 or press at any time.
GENERAL OPTIONS Chapter 4. Contents 4 GENERAL OPTIONS ...............................................................................4 - 3 4.1 Active Pump ..........................................................................................4 - 3 4.2 Temperature .........................................................................................4 - 4 4.2.1 Temperature Source ..................................................................................4 - 5 4.2.
GENERAL OPTIONS 4-2
GENERAL OPTIONS 4 GENERAL OPTIONS The General Options screen gives access to options that are not directly related to the titration process or pH / mV measurement. To access this screen, press from the main screen. The available menus are described below: 4.1 Active Pump The HI 901 and HI 902 titrators can be equipped with one or two dosing systems (pump & burette). Only one pump can be active at a time. This option allows the user to set active either pump 1 or pump 2.
GENERAL OPTIONS Highlight the pump to be activated. Press and the highlighted pump is set as temporarily active (for the duration of the current running session). After the titrator is restarted, the active pump will be reset to the one set as default. Press and the highlighted pump is set as active immediately in the current session and all following running sessions. If only one pump is connected to titrator, the Active Pump screen will be as follows: 4.
GENERAL OPTIONS 4.2.1 Temperature Source The Temperature Source screen allows the user to select the temperature source, used for pH temperature compensation. When the Automatic Temperature Compensation option is selected, the temperature displayed on the main screen is read by the temperature probe. Also the ATC icon is displayed. When the Manual Temperature option is selected, a preset value of the temperature is used for temperature compensation and the Manual icon is displayed on the main screen.
GENERAL OPTIONS 4.2.3 Temperature Units The following temperature units can be selected. The temperature ranges are as displayed in the Temperature Units screen. The titrator will automatically convert the measured temperature to the new unit. 4.3 Date and Time Setting This screen allows the user to set the date and time. By pressing 4-6 the cursor will cycle to the next field.
GENERAL OPTIONS 4.4 Display Settings This screen allows the user to customize the viewing features of the display. Option Keys: Turns the backlight off Turns the backlight on Increases the backlight saver time interval Decreases the backlight saver time interval The contrast can be adjusted using and The backlight intensity can be adjusted using keys. and keys. There are 8 gradual steps both for contrast and backlight intensity, ranging from 0 to 7.
GENERAL OPTIONS 4.5 Beeper This screen allows the beeper to be enabled (Beeper On) or disabled (Beeper Off). The beeper will sound after a titration is completed, when an invalid key is pressed or when a critical error occurs during titration. 4.6 Stirrer This screen allows the stirrer to be enabled or disabled.
GENERAL OPTIONS 4.7 Language Select the language from the available languages listed in this screen. 4.8 Daily Standardization Reminder This screen allows a programmable reminder to appear when it is time to standardize the pH electrode. The Standardize Electrode reminder message will appear each day at the programmed time. Once standardization has been performed, the reminder will disappear until the next day. The reminder can be disabled by pressing .
GENERAL OPTIONS 4.9 Periodic Standardization Reminder This screen allows a programmable reminder to appear when it is time to standardize the pH electrode. The Standardize Electrode reminder message will appear when it is time for the electrode to be re-standardized. Once the new standardization has been performed, the reminder will disappear and the timer will reset. The reminder can be disabled by pressing 4.10 .
GENERAL OPTIONS After the new titrant volume has been set on titrator (in the Total Volume Alert screen), a warning message appears reminding the user to perform titrant re-standardization. The reminder can be disabled by pressing . The range is from 0 to 10,000 mL. 4.11 Titrant Age Reminder This screen allows a programmable reminder to appear when it is time to verify the titrant concentration or to change the titrant due to concentration confidence loss.
GENERAL OPTIONS The option keys allow the following operations: Deletes the highlighted file Deletes all currently displayed files Copies the highlighted file from titrator to floppy disk Copies all currently displayed files from titrator to floppy disk Returns to the General Options screen The status of the transfer (successful / unsuccessful) and the file name of the currently processed file are displayed during copying or deleting.
GENERAL OPTIONS The file types that can be transferred are: Standard Method Files User Method Files Report Files - HI*.MTD - USER*.MTD - *.RPT Selection of the file types can be performed with the and keys. The number of files and the name of each file found on the floppy disk is displayed on the screen. The option keys allow the following operations: Deletes the highlighted file from diskette. Deletes all currently displayed files from diskette. Copies the highlighted file from diskette to titrator.
GENERAL OPTIONS 4.15 Reset to Default Settings This option restores the manufacturer settings. Note: Please be careful !!! This will also delete all the user created methods and restore all manufacturer settings such as titrator configuration, standard method parameters, etc. 4.16 Update Software This screen allows the user to update the titrator software from a floppy disk.
METHODS Chapter 5. Contents 5 METHODS .............................................................................................. 5 - 3 5.1 Selecting Methods ................................................................................ 5 - 3 5.2 Standard Methods ................................................................................. 5 - 4 5.2.1 Upgrading Standard Methods .................................................................... 5 - 4 5.2.2 Deleting Standard Methods .........
METHODS 5.5.11 Calculation ............................................................................................5 - 27 5.5.11.1 Standard Titrations ............................................................................ 5 - 27 5.5.11.2 Back Titrations (HI 902 only) ............................................................... 5 - 34 5.5.12 Dilution Option ..................................................................................... 5 - 39 5.5.13 Titrant Name ........................
METHODS 5 METHODS The titrator automatically performs a complete analysis. A complete analysis comprises sample preparation, dispensing of titrant solution, stirring, measuring and waiting times, recognition of the end point and storing titration results. All the parameters that a titration requires are grouped into a method. The titrator is supplied with a pack of standard methods.
METHODS To select a method, highlight the method and press method will be displayed on the main screen. 5.2 . The name of the selected Standard Methods The standard methods are developed by the manufacturer for the most common types of analysis. Also, each standard method can be used as a model to create a new user method. Only specific method parameters can be modified by the user (see 5.5 Method Options section). 5.2.1 Upgrading Standard Methods The titrator will accept up to 50 standard methods.
METHODS 5.2.2 Deleting Standard Methods You can remove unnecessary standard methods from titrator following the next steps: Insert any diskette into the titrator. From the main screen press Using the and . keys, highlight the Save Files to Diskette option and press ; Using the and keys, navigate through the file types menu to find standard method files. The available standard methods will be displayed. Press the Press or keys to remove unnecessary standard methods.
METHODS 5.3.1 Creating User Methods To create a new user method start from a standard or user method and follow these steps: Press from the main screen. Using the and keys, highlight an existing method from the methods list. Press . A new user method will be generated. Press to activate the new created user method. Note: Only a limited number of user methods can be generated. If the limit of standard and user methods (100 methods) is reached, a warning message will be displayed. 5.3.
METHODS 5.4 View / Modify Method To modify the methods parameters, press from the main screen. A list of all the parameters for the selected method will be displayed. Using the the option that you want to modify and choose and keys, highlight . Save method: From the View / Modify Method screen, press . You can choose to save the modifications of the method parameters or to discard them.
METHODS 5.4 Method Options 5.5.1 Naming the User Method This option allows you to enter a name for the new method (up to 24 characters). Use the to add the highlighted arrow keys to navigate through the character table. Press character to the method name. 5.5.2 Titration Type (HI 902 only) In order to make an analysis you have to choose the type of titration: Standard Titration A titration with a pH or mV equivalence point detection. A titration with fixed pH or mV end point.
METHODS Back Titration A titration with a pH or mV equivalence point detection, consisting of two titration phases: Phase 1 the sample is consumed by a known volume and concentration of titrant 1. A sufficient amount of titrant 1 is dispensed to surpass the equivalence point in order to react quickly with the sample. Phase 2 the excess of titrant 1 is titrated with the titrant 2 to the equivalence point. Finally, the concentration of the sample will be determined.
METHODS 5.5.3.1 Linear Dosing This type of dosing uses equal volume doses of titrant as shown in the graph below. Linear Dosing The Linear Dosing option is recommended for slower, difficult nonaqueous titrations or certain specific analysis. Note: For steep and normal titration curves, smaller volume increments are recommended, to obtain many measured points around the equivalence point. For flat titration curves, larger volume increments are recommended for equivalence point detection.
METHODS The allowed 0.001 to 0.001 to 0.005 to 0.005 to 5.5.3.2 ranges for dosing volume are: 4.500 mL for a 5 mL burette 9.000 mL for a 10 mL burette 22.500 mL for a 25 mL burette 45.000 mL for a 50 mL burette Dynamic Dosing The titrant is added in volumes that depends on the proximity of the end point as shown in the graph below. The titrator determines the titrant dose by trying to maintain a certain potential change (delta E) with each addition.
METHODS As a result, far from the end point, larger doses are made, reducing the total titration time. Closer to the end point, smaller doses are made, providing more data and higher accuracy in the critical end point region. The following parameters must be set: min Vol: Sets the smallest dose volume to be dispensed during titration. The min Vol must be greater or equal than: 0.001 mL for a 5 mL burette 0.001 mL for a 10 mL burette 0.005 mL for a 25 mL burette 0.
METHODS 5.5.4 End Point Mode 5.5.4.1 Fixed End Point (pH or mv) Fixed End Point (pH): The titration is normally terminated when the preset pH value has been exceeded. The reported end point volume is interpolated between the dispensed volume when pH is under the preset pH value and the dispensed volume when pH exceeded the preset pH value. The range is from - 2.000 to 20.000 pH.
METHODS Fixed End Point (mV): The end point detection algorithm is the same as for pH, but the threshold value is expressed in mV. The range is from - 2000.0 to 2000.0 mV. 5.5.4.2 Equivalence End Point (pH or mv) The titration is normally terminated when the equivalence point is detected (the point where the added quantity of titrant equals the quantity of analyte present in the sample, according to the chemical combination ratio).
METHODS Number of Equivalence Points (HI 902 only) The titrator can perform a titration with more than one equivalence point. Up to 5 equivalence points can be detected. End Point Determination The first and the second derivative of the S-shaped titration curve can be used to detect the equivalence point. The equivalence point detection algorithm requires three more doses to be dispensed in the analyte after the equivalence point is reached.
METHODS This is rigorously exact only for symmetric S-shaped titration curves. For non-symmetric curves, the effect of this theoretical error can be minimized by smaller doses (more measurement points) around the equivalence point. 1st Derivative: When first derivative is used to recognize the equivalence point, the point where the first derivative reaches the maximum value corresponds to the titration curve inflection point (EQP).
METHODS 2nd Derivative: When second derivative is used to recognize the equivalence point, the zero crossing point of the second derivative corresponds to the titration curve inflection point (EQP). The detection algorithm searches for the point where the second derivative changes the sign. Also, the first derivative, corresponding to the checked point must be greater than the threshold value (see Recognition Options on page 5-17).
METHODS Threshold: This parameter must be set by the user in according with the analysis. The threshold represents the absolute value of the first derivative, expressed in |mV/mL| (absolute value), below which the detection algorithm does not search for the equivalence point. Range is between 1 and 9999 mV/mL. The recommended value for the threshold is around 40% of the estimated maximum absolute value of the first derivative.
METHODS Range: Range is an optional feature for equivalence point recognition. It represents a set mV or pH range for equivalence point detection. The Range option can be enabled by selecting YES in the Range Options screen. Limit 1 - The first limit of the range attained during the titration: This range can be from -2.000 pH to 20.000 pH (for pH equivalence point). This range can be from -2000.0 mV to 2000.0 mV (for mV equivalence point).
METHODS Filtered Derivatives: Filtered Derivatives is an optional feature for equivalence point recognition. This option adds a filtering procedure in the 1st and 2nd derivative computation algorithm that reduces the influence of pH or mV noise. The Filtered Derivatives option can be enabled by selecting YES in the Filtered Derivatives Option screen.
METHODS The valid pre-titration volume is between the ranges shown below: 0.001 to 4.500 mL for a 5 mL burette 0.001 to 9.000 mL for a 10 mL burette 0.005 to 22.500 mL for a 25 mL burette 0.005 to 45.000 mL for a 50 mL burette If no pre-titration volume is used, 0.000 mL should be entered. Note: A pre-titration volume is highly recommended whenever possible. When fewer linear doses are used the overall titration duration considerably shortens. 5.5.
METHODS 5.5.7 Measurement Mode During titration, the acquisition of the potential (mV) value of the solution, can be performed in two ways, by using either Signal Stability or Timed Increment option. Addition of the next dose is performed immediately after the potential is measured. 5.5.7.1 Signal Stability When Signal Stability option is selected, the titrator acquires the potential (from solution) only when the stability condition is reached.
METHODS The signal stability window (condition) represents the time interval ∆t during which the potential measured in solution (mV) is confined inside the potential interval ∆E (see the boxes on the chart). The new signal value is acquired if the stability condition is reached but not before the minimum waiting time (t min wait) has elapsed. If the t max wait time has elapsed and the stability condition is not reached, the potential is acquired (and a new dose is added).
METHODS 5.5.7.2 Timed Increment When Timed Increment option is selected, the acquiring of the potential (mV) value from the solution is made at a fixed time interval (no signal stability check). The time period between two acquisitions must be set according with the used reaction and the time response of the electrode. The range is from 2 to 180 seconds.
METHODS 5.5.8 Electrode Type Enter the type of the electrode, up to 24 characters. The electrode type will appear in the titration report. 5.5.9 Blank Option This feature allows the user to select the procedure for the blank calculations (where V is the volume of titrant dispensed during the titration and Blank is the volume of titrant consumed by the blank sample).
METHODS If one of the options (V-Blank or Blank-V ) is selected in the View / Modify Method screen the Blank Value option will became active and the value of blank can be set (in liters). 5.5.10 Imposed Current (HI 902 only) When Fixed End Point (mV) (see 5.5.4 End Point Mode) is set, the Imposed Current option will become available. Using the imposed current feature in end point redox titrations has a great advantage on the speed of the redox reactions.
METHODS The imposed current can be set from -100 µA to 100 µA with 1 µA resolution. 5.5.11 Calculations The titrator will make certain calculations in order to obtain the result of the analysis. The result is computed starting from the end point volume (titrant volume at the equivalence point), using a formula set by the user. 5.5.11.1 Standard Titrations Edit Variable Values This option allows the user to change the values of the variables used in a previously selected calculation.
METHODS Sample Calculations by Weight This calculation should be used when the concentration of an analyte is determined in a solid sample. The results are based on the initial sample weight (in grams). When you choose this formula, select the Titrant Unit first and then the Final Result Unit. The titrator will provide the results based on the titrant and sample units selected.
METHODS If the titrant unit is selected as M (mol/L) and the final sample unit as g/Kg (grams/kilogram) the formula used to generate the result is displayed below: Some variables can be set according to the amount of sample and titrant used. Sample Calculations by Volume This calculation should be used when the concentration of an analyte is determined in a liquid sample. The results are based on the initial sample volume (in milliliters).
METHODS M (mol/L) N (eq/L) mg/L µg/L mmol/L mg/mL g/100 mL eq/L meq/L (Molarity; moles/liter) (Normality; equivalences/liter) (milligrams/liter) (micrograms/liter) (millimoles/liter) (milligrams/milliliter) (grams/100 milliliters) (equivalences/liter) (milliequivalences/liter) If the titrant unit is selected as N (eq/L) and the final sample unit as g/L (grams/liter), the formula used to generate the result is displayed below. Some variables can be set according to the amount of sample and titrant used.
METHODS The titrator will provide the calculation based on the titrant unit selected. Standardize Titrant by Volume This calculation should be used when the titrant is standardized (concentration determination) using a standard solution. Determination of the titrant concentration is based on the primary standard volume (in milliliters). The titrator will perform the calculation based on the titrant unit selected.
METHODS eq/L meq/L (equivalences/liter) (milliequivalences/liter) The formula can be used either for titrant standardization or for sample analysis.
METHODS Titrant Concentration: The units for titrant concentration can be: mol/L (concentration unit of titrant) eq/L (concentration unit of titrant) g/L (concentration unit of titrant) mg/L (concentration unit of titrant) One of the general factors should be used as a stoichiometric factor, the other as unit conversion factor and the third as weight conversion factor.
METHODS 5.5.11.2 Back Titrations (HI 902 only) Sample Calculations by Weight When choosing this formula, select the titrant 1 unit, the titrant 2 unit and then the final result unit.
METHODS If the titrant 1 unit is selected as M (mol/L), titrant 2 unit is selected as M (mol/L) and the final result unit as mg/g (milligrams/gram) the following formula is used to calculate the amount of titrant 1 (used in the first stage of back titration or direct titration) and will be as follows: The formula is based on an approximation: the sample concentration is 100% w/w.
METHODS In order to calculate this volume, the remaining titrant 1 volume is titrated (pH/mV equivalence point titration) with titrant 2.
METHODS ⇐ Select the titrant 2 unit ⇐ Select the final result unit The titrator will provide the calculation based on the titrants and sample units selected. After you have selected the titrant 1, titrant 2 and the final result units the titrator will display a screen with a formula used to calculate the amount of titrant 1 (used in the first stage of back titration).
METHODS This calculation formula is used as an approximation of the sample concentration (sample max conc.). This formula can be used when we have an expected sample concentration (eg. we know that the sample concentration must be around 1 M (mol/L)). If we dont have an expected sample concentration, then from the View/Modify Method screen: .
METHODS When all the parameters are set, press Concentration formula: to proceed with the Calculating Sample Generic Formula This option allows the user to define their calculation formula for the Direct Titration Volume, Calculating Excess Volume of Titrant 1 and Final Sample Concentration in a solid or liquid sample. 5.5.12 Dilution Option This option enables the dilution calculations to be made (when the initial sample is diluted, the titration is made with an aliquot of the diluted sample).
METHODS The sample size used in the calculations will be: Analyte size to be diluted * Aliquot Volume Final Dilution Volume 5.5.13 Titrant Name Enter the name of the titrant (up to 24 characters). This name will appear in the titration report. 5.5.14 Titrant Concentration Enter the concentration of the titrant to be used. When determining the titrant concentration only the unit is displayed and the titrant concentration can not be set. 5.5.
METHODS 5.5.16.1 Fixed Weight or Volume Each titration will use the same analyte weight or volume as preset in the calculations. 5.5.16.2 Manual Weight or Volume Each titration will use a different analyte weight or volume. The titrator will prompt for the analyte volume at the beginning of each titration. 5.5.17 Titrant 1 Entry (HI 902 only) Select the mode for evaluating the necessary quantity of titrant 1 used in the back titration process (phase 1). 5.5.17.
METHODS 5.5.18 Maximum Titrant Volume The maximum titrant volume used in the titration must be set according to the analysis. If the titration end point (fixed or equivalence End Point) is not reached, the titration will be abnormally terminated after the maximum titrant volume has been dispensed. The error message (Limits Exceeded) will appear on the display. Range is from 0.100 to 100.000 mL. 5.5.19 Stirring Speed The stirring speed can be set between 100 and 2500 RPM with 100 RPM resolution.
METHODS 5.5.20 Potential Range The allowable input potential range can be set by the user. Outside of these limits, if the titration is in progress, the titration will be abnormally terminated and an error message will appear. These limits provide protection against a titration that does not generate an end point due to potential over-range. The ranges must be set within -2000.0 to 2000.0 mV. 5.5.21 Volume/Flow Rate The flow rate for the dosing system can be total burette volume, as follows: 0.
METHODS 5.5.22 Signal Averaging This option enables or disables a filtering on the mV/pH reading. If 1 Reading is selected, the filtering is disabled. Otherwise, the titrator will take the last reading and place it into a moving window along with the last 2, 3 or 4 readings (depending on the selected option). The average of those readings is displayed and used for calculations. Averaging more readings is helpful when a noisy signal is received from the electrode. 5.
TITRATION MODE Chapter 6. Contents 6 TITRATION MODE ................................................................................. 6 - 3 6.1 Titration Start ....................................................................................... 6 - 3 6.1.1 In Progress Titration ................................................................................. 6 - 3 6.1.2 Suspend Titration ..................................................................................... 6 - 3 6.1.3 On-line Graph ..
TITRATION MODE 6-2
TITRATION MODE 6 TITRATION MODE 6.1 Titration Start Before beginning to perform a titration make sure that the following conditions are met: A pump is properly installed and selected as active. A burette is inserted in the pump and filled with titrant. The aspiration tube is inserted in the titrant bottle and the dispensing tube is over the analyte beaker. The electrode and the temperature probe is inserted in the analyte beaker.
TITRATION MODE The S-shaped curve and the derivative curve are scaled to fit simultaneously inside the display. Also, when the titration is normally terminated (end point detected successfully), the end point volume value marked with a cross is displayed on the graph. The contents of the graph as related to an end point type, is as follows: Equivalence End Point (pH) - the pH curve and the selected derivative vs volume is displayed.
TITRATION MODE - allows you to save the graph as a bitmap file. Available only when the titration is finished (after end point detection). 6.2 Titration Stop The titration can be finished in one of the modes described below: Titration Completed. The titration was successfully terminated (with end point successfully detected). This is the only mode with valid final result values. Manually Terminated. The current titration was manually terminated before end point detection was achieved.
TITRATION MODE 6-6
pH & mV MODE Chapter 7. Contents 7 pH & mV MODE ......................................................................................7 - 3 7.1 pH Mode ................................................................................................ 7 - 3 7.1.1 Display .................................................................................................... 7 - 3 7.1.2 pH Menu ..................................................................................................7 - 4 7.1.2.1 7.1.2.
pH & mV MODE 7-2
pH & mV MODE 7 pH & mV MODE The HI 901 / HI 902 titrators can be used to log precise pH or mV measurements. By pressing from the main screen, the titrator will switch to the pH or mV screen (depending on the End Point Mode option selected from View / Modify Method screen). 7.1 pH Mode 7.1.1 Display The pH screen shown below will help you understand the following explanations.
pH & mV MODE 7.1.2 pH Menu Options from this screen (except the Resolution option) refer to the pH electrode calibration functions. 7.1.2.1 Add a Buffer (Auto-Entry) Add a new buffer (up to 5 buffers can be added) or replace an existing one from the electrode standardization table. The buffer is now automatically recognized and temperature compensated from the created buffer list (see section 7.1.2.4 Edit Buffer Set). The titrator accepts electrodes slope between 80 to 105%. 7.1.2.
pH & mV MODE 7.1.2.3 Clear Standardization Deletes electrode standardization. The titrator will prompt for confirmation. 7.1.2.4 Edit Buffer Set Creates a unique, auto-recognized buffer set. The new calibration standard buffer will be checked from the set described below. Available buffers include: Hanna: CRC: DIN: NIST: 4.01, 1.68, 1.09, 4.01, 6.86, 3.56, 3.06, 6.86, 7.01, 9.18, 10.01 4.01, 6.87, 7.41, 9.18, 12.46 4.65, 6.79, 9.23, 12.75 7.
pH & mV MODE 7.1.2.5 Graph Standardization Data Graphs the electrode standardization data (pH vs mV). 7.1.2.6 pH Standardization Data Displays the electrode standardization data in a tabular form. 7.1.2.7 Resolution You can choose between 0.1, 0.01 and 0.001 resolution for the displaying pH values. 7.2 mV Mode 7.2.1 Display The mV screen shown below will help you understand the following discussion.
pH & mV MODE 7.2.2 mV Menu By pressing 7.2.2.1 , the following screen will be displayed: Auto-Zero Relative mV This sets the relative potential to zero by saving the current potential and subtracting it from subsequent readings. If an absolute zero is needed, replace the electrode with a shorting cap before performing this action. Note: The auto-zero will affect the mV reading and therefore the pH value (new displayed relative mV reading will be used to calculate the new pH value). 7.2.2.
pH & mV MODE 7.2.2.3 Clear Relative mV Offset Sets the mV offset to zero. With this option, the previous relative value or auto zero is cleared. 7.3 Logging When in pH or mV mode, logging can be either manual or automatic. Before starting an automatic or manual logging operation, please customize a unique report for the saved pH and mV measurements, as follows: From the pH or mV screen, press to display the Data Parameters screen.
pH & mV MODE 7.3.1 Automatic Logging To start automatic logging pH or mV readings, follow these steps: From the pH or mV screen, press to display the Data Parameters screen. Highlight the Logging Interval pH/mV option and press Logging Interval screen. to display the Enter the time interval between each consecutive record.
pH & mV MODE 7-10
AUXILIARY FUNCTIONS Chapter 8. Contents 8 AUXILIARY FUNCTIONS ........................................................................8 - 3 8.1 Burette .................................................................................................. 8 - 3 8.1.1 Prime Burette ........................................................................................... 8 - 3 8.1.2 Rinse Tip ................................................................................................. 8 - 4 8.1.
AUXILIARY FUNCTIONS 8-2
AUXILIARY FUNCTIONS 8 AUXILIARY FUNCTIONS 8.1 Burette To access the Burette screen, press Highlight the desired option and then press 8.1.1 from the main screen. . Prime Burette The Prime Burette option is used to mechanically fill the burette before starting a set of analysis. Two rinses cycles of burette are shown in the figure below. The dispensing tube is connected on the right side and the aspiration tube on the left side.
AUXILIARY FUNCTIONS To prime the burette, select Prime Burette from the Burette screen. Enter the number of rinses and press . The number of burette rinses can be set between 1 and 5 (we recommend at least three rinses to assurre that the air bubbles are completely removed). 8.1.2 Rinse Tip A 2 mL dose of titrant will be dispensed from the burette when this operation is started. This operation will eliminate the air from the dispensing tip. 8.1.
AUXILIARY FUNCTIONS The manual dispense volume must be between the limits shown bellow: 0.001 0.001 0.005 0.005 8.1.4 to 4.500 mL to 9.000 mL to 22.500 mL to 45.000 mL for for for for a a a a 5 10 25 50 mL mL mL mL burette burette burette burette Purge Burette This option allows titrant evacuation before cleaning and/or storing the burette. The burette is flushed twice. Note: Before starting this operation, remove the aspiration tube from the titrant bottle.
AUXILIARY FUNCTIONS 8.3 Results The Data Parameters screen contains options regarding data parameters from the titrator, as follows: 8.3.1 Review Last Titration Report Selecting this option, the last titration data can be reviewed. The last titration report file can be displayed or printed. Also, the titration graph can be reviewed by selecting . The information that can be reviewed in the report is based on the selections made in the Setup Titration Report screen.
AUXILIARY FUNCTIONS 8.3.2 Review Available Reports Up to 100 reports can be recorded on the titrator. To view one of the recorded reports highlight a report and then press Report . All the reports stored in the titrator (titration and pH/mV reports) can be reviewed and printed. The report contains only the information selected in the Setup Titration Report and Setup pH/mV Report screens during report configuration. The keys are the same as in the previous section (8.3.1 Review Last Titration Report).
AUXILIARY FUNCTIONS Operator Name - Allows the operator name to be recorded in each report. Electrode Name - Allows the electrode name to be recorded in each report. Fields 1, 2, 3 - Allows any additional information to be recorded in each report. The fields that must be present in the Titration Report must be selected from the Setup Titration Report screen (see 8.3.7 Setup Titration Report section). 8.3.4 Instrumentation Data Displays titrator configuration data.
AUXILIARY FUNCTIONS 8.3.5 Logging Interval pH/mV Allows the user to setup a time interval for auto-logging while in pH or mV mode (see 7.3 Logging section). 8.3.6 Setup pH/mV Report Customize a unique report to record the pH and mV measurements. 8.3.7 Setup Titration Report Customize a unique report to record the titration results. An asterisk means that it will be included in the titration report.
AUXILIARY FUNCTIONS 8-10
MAINTENANCE, PERIPHERALS Chapter 9. Contents 9 MAINTENANCE, PERIPHERALS .............................................................9 - 3 9.1 Burette Maintenance ............................................................................ 9 - 3 9.1.1 Burette Assembly ......................................................................................9 - 3 9.1.2 Changing Burette ...................................................................................... 9 - 3 9.1.3 Disassembling Burette ...
MAINTENANCE, PERIPHERALS 9-2
MAINTENANCE, PERIPHERALS 9 MAINTENANCE, PERIPHERALS 9.1 Burette Maintenance 9.1.1 Burette Assembly The included burette is delivered with a 25 mL syringe inside and with all the accessories mounted (see 2.1 Unpacking section for burette assembly details). Note: The dispensing tube has one flat-shaped end and the other one is equipped with a dispensing tip. (See 2.1 Unpacking section for the accessories list.) 9.1.
MAINTENANCE, PERIPHERALS 9.1.3 Disassembling Burette To dismount the dispensing tube and the aspiration tube follow these steps: Slide up the protection tube (4). Remove the tube lock (5) from the burette holder. Slide the mounting tool (3) over the dispensing tube. Unscrew the fitting (2). Remove the mounting tool (3) from the tube. Remove the tube. Repeat these steps for the aspiration tube. 9.1.
MAINTENANCE, PERIPHERALS To attach the burette to the pump simply slide the burette into the pump support as shown in the figure presented in 9.1.2 Burette Changing section. 9.1.5 Cleaning Burette To clean the burette, follow these steps: If the burette is filled with liquid, remove the aspiration tube from the titrant bottle and execute purge burette operation (see 8.1.4 Purge Burette section).
MAINTENANCE, PERIPHERALS Clean both the piston and the syringe with appropriate solvents, then with ethylic alcohol and then rinse them several times with deionized water, titrant solvent or just titrant. Remove the excess liquid. Warning: Avoid contact with the titrant with bare hands. Avoid spilling titrant in the working place. Clean the external side of the syringe and piston to remove aggressive chemicals.
MAINTENANCE, PERIPHERALS 9.1.6 Burette Preparation (Titrant Filling) Before starting a titration, the burette must be properly filled with titrant in order to obtain a good and repeatable result. To fill the burette, follow the next steps and recommendations: If necessary, clean the burette and make sure it is empty. From the main screen press . Highlight Prime Burette option and press .
MAINTENANCE, PERIPHERALS 9.2 Fuses Replacement To replace the fuses, follow these steps: Turn off the titrator. Remove the power cord from the power connector located on the rear side of the titrator case. With a screw driver open the fuse holder lid. Extract the fuse holder. Replace the fuses (for recommended fuses replacement please see the label located above the main power switch). Close the fuse holder lid. Connect the power cord.
MAINTENANCE, PERIPHERALS 9.3.1 Connecting an External Display The information shown on the titrator display can be viewed also on a Standard VGA display connected with a 15-pin cable, as presented below. Connect the external display to the display socket. Turn on the titrator and then the external display. 9.3.2 Connecting an External PC Keyboard This connection allows you to use an external PC Keyboard in addition to titrators keypad.
MAINTENANCE, PERIPHERALS The correspondence between the Titrators Keypad and the United States 101-type external keyboard are: External PC Keyboard (United States 101) Titrator Keypad Function Key F-1 Function Key F-2 Function Key F-3 Function Key F-4 Function Key F-5 Option Key 1 (from left to right) Function Key F-6 Option Key 2 (from left to right) Function Key F-7 Option Key 3 (from left to right) Function Key F-8 Option Key 4 (from left to right) Function Key F-9 Option Key 5 (from left to
MAINTENANCE, PERIPHERALS 9.3.3 Connecting a Printer A variety of parallel printers can be connected to the parallel port of the titrator using a standard DB25pin cable. Warning: The titrator and the external printer must be both turned OFF from the main switch before making the connection. Connect the external printer to the standard 25pin Socket. Turn on the titrator and then the printer. 9.3.
MAINTENANCE, PERIPHERALS Warning:The titrator and the external PC must be both turned OFF from the main switch before making the connection. Connect the cable to the standard DB9 pin Socket. Connect the cable to the serial communication port on the PC. Turn on the titrator and then the computer.
APPENDIX 1 Appendix 1. Contents A1 TECHNICAL SPECIFICATIONS ..............................................................
APPENDIX 1 A1-2
APPENDIX 1 A1 TECHNICAL SPECIFICATIONS mV Range Accuracy Resolution pH Range Accuracy Resolution - 2.000 to 20.000 pH ±0.001 pH 0.1 / 0.01 / 0.001 pH Temperature Range - 5.0 to 105.0 °C 23.0 to 221.0 °F 268.2 to 378.2 K ±0.1 °C 0.1 °C Accuracy Resolution - 2000.0 to 2000.0 mV ±0.1 mV 0.1 mV Dosing Accuracy 0.1 % of full nominal volume of the burette Display Resolution 0.
APPENDIX 1 Titer Determination. Fixed mV or pH End Point Detection. Single Equivalence Point Detection, with the 1st or 2nd Derivatives of the titration curve. Multiple Equivalence Point Detection (HI 902 only) Flexible Concentration Calculations, with many concentration units.
APPENDIX 2 Appendix 2. Contents A2 BACK TITRATION (HI 902 only) ..........................................................A2-3 A2.1 Applicability Domain ........................................................................... A2-3 A2.2 Method Principles ................................................................................ A2-3 A2.3 Back Titration Example ...................................................................... A2-3 A2.3.1 Introduction ...........................................
APPENDIX 2 A2-2
APPENDIX 2 A2 BACK TITRATION (HI 902 only) A2.1 Applicability Domain Back titrations are generally used for one of these reasons: Reaction kinetics are too slow for the direct titration of the analyte. The metal precipitates at the desired pH (complexometric titrations). The reaction between titrant and analyte produces some auxiliary compounds (e.g. CO2) that can affect the mV signal and also the equivalence point detection. Heavily soluble analyte in the solvents used.
APPENDIX 2 and back titrate the remaining acid with NaOH to determine the amount of CaCO3 present. 2HCl excess + 2NaOH > 2NaCl + 2H2O In order to obtain an accurate value for the concentration of the titrated antacid, we need to know the exact concentration of NaOH and HCl used. The final concentration is expressed as mg/g CaCO3. A1.3.2 Setting Up the Method Parameters Use the following parameters to program the method (see 5.
APPENDIX 2 A2.3.3 Preparing the Sample For this analysis can use commercial antacid pills. Crush a few pills in a mortar and separate a quantity weighting around 0.5 mg from the resulting powder. Pour about 20 mL distilled and deionized water into a 150 mL beaker and then add the sample powder. Raise the stirrer assembly. Place the beaker under the stirrer assembly. Lower the stirrer assembly until it rests on its positioning collar.
APPENDIX 2 Slide the stirrer assembly up. Put the beaker on a hotplate. Heat gently until all the effervescence has ceased, then boil it for 1-2 minutes. Some of the inactive tablet material may not dissolve; however, this should not interfere with the titration. Cool the solution to the room temperature and put the beaker under the stirrer asembly. Lower the stirrer assembly until it rest on its positioning collar.
APPENDIX 3 Appendix 3. Contents A3 MULTIPLE EQUIVALENCE POINTS (HI 902 only) ................................. A3-3 A3.1 Applicability Domain ............................................................................ A3-3 A3.2 Perform a Multi-Equivalence Point Titration ...................................... A3-3 A3.3 Titration Example ................................................................................
APPENDIX 3 A3-2
APPENDIX 3 A3 MULTIPLE EQUIVALENCE POINTS (HI 902 only) A3.1 Applicability Domain In case of: determining the components concentration from a synthetic mixture (e.g. Mixture of HCl, CH3COOH, NH4Cl). determining the concentration of a polyprotic acid in its titrable ionization stages (e.g. H3PO4, two equivalence points in aquogenos medium). A3.
APPENDIX 3 A3.3 Titration Example As an example of a multi-equivalence point titration we take the titration of a mixture containing HCl, CH3COOH and NH4CL with Sodium Hydroxide. During this type of titration the user is able to view the following information: After first equivalence point is detected, the titration screen will show number of equivalence points detected. and the By pressing the titrator will display EQ Points Report.
APPENDIX 3 The graph displays the equivalence points with a cross. Near each cross the equivalence titrant volume is diplayed. The volume is calculated: from titration beginning (for the first equivalence point marked with a cross). the next volumes (marked with a cross) are calculated as the difference betwen the total volume dispensed until the current equivalence point is reached) and the sum of the already detected equivalence points.
APPENDIX 3 A3-6
APPENDIX 4 Appendix 4. Contents A4 ACCESSORIES ................................................................................... A4-3 A4.1 Solutions ........................................................................................... A4-3 A4.1.1 pH Calibration Solutions ........................................................................A 4 - 3 A4.1.2 pH Calibration Solutions in FDA Approved Bottle ..................................... A 4 - 3 A4.1.3 Electrode Cleaning Solutions ......
APPENDIX 4 A4-2
APPENDIX 4 A4 ACCESSORIES A4.1 Solutions A4.1.1 pH Calibration Solutions HI HI HI HI HI HI HI HI HI HI HI HI HI HI HI HI 70004C 77400C 7004M 7004L 7006M 7006L 70007C 7007M 7007L 7009M 7009L 770710C 7010M 7010L 7001M 7001L A4.1.2 HI HI HI HI HI 8004L 8006L 8007L 8009L 8010L A4.1.3 HI HI HI HI HI HI HI HI 7061M 7061L 7073M 7073L 7074M 7074L 7077M 7077L > > > > > > > > > > > > > > > > pH pH pH pH pH pH pH pH pH pH pH pH pH pH pH pH 4.01 Buffer Solution, 20 mL 4.01 & 7.
APPENDIX 4 A4.1.4 HI HI HI HI HI HI Electrode Cleaning Solutions in FDA Approved Bottle 8061M 8061L 8073M 8073L 8077M 8077L A4.1.5 > > > > > > General Purpose Solution, 230 mL General Purpose Solution, 460 mL Protein Cleaning Solution, 230 mL Protein Cleaning Solution, 460 mL Oil & Fat Cleaning Solution, 230 mL Oil & Fat Cleaning Solution, 460 mL Electrode Storage Solutions HI 70300M HI 70300L > > Storage Solution, 230 mL Storage Solution, 460 mL A4.1.
APPENDIX 4 A4.2 Sensors A4.2.1 pH Electrodes HI 1043B / HI 1040S Glass-body, double junction, refillable, combination pH electrode. Use: strong acid/alkali. HI 1053B / HI 1050S Glass-body, triple ceramic, conic shape, refillable, combination pH electrode. Use: emulsions. HI 1083B Glass-body, micro, Viscolene, nonrefillable, combination pH electrode. Use: biotechnology, micro titration. HI 1131B / HI 1111S Glass-body, single junction, refillable, combination pH electrode. Use: general purpose.
APPENDIX 4 FC 210B Glass-body, double junction, conic, Viscolene, combination pH electrode. Use: milk, yogurt. FC 220B Glass-body, single junction, refillable, combination pH electrode. Use: food & wine processing. FC 911B Plastic-body (Kynar®), double junction, refillable with built-in amplifier, combination pH electrode. Use: very high humidity. HI 1413B / HI 1410S Glass-body, single junction, flat tip, Viscolene, combination pH electrode. Use: surface measurement. A4.2.
APPENDIX 4 A4.2.4 Extension Cable for Screw-Type Electrodes only (Screw to BNC Connector) HI 7855/1 Extension cable 1m (3.3') long. A4.2.5 Temperature Sensor HI 7662-T Temperature probe with 1 m (3.3') paneled cable. Ultem® is registered Trademark of General Electric Co. Kynar® is registered Trademark of Pennwalt Corp.
APPENDIX 4 A4.
APPENDIX 4 Shorting cap ion Titrat ries 0 Se HI 90 ms Syste HI om ainst.c ann w.
APPENDIX 4 MAN901/902 09/04 R0 A4-10