Hanna Instruments HI 84442 User Manual

Instruction Manual

HI 84442

TOTAL ALKALINITY FOR VERY

LOW RANGE

MINITITRATOR & pH METER

for Water Analysis

www.hannainst.com

Dear Customer, Thank you for choosing a Hanna product. This manual will provide you with the necessary

information for the correct use of the instrument. Please read it carefully before using the meter. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst.com.

This instrument is in compliance with

directives.

TABLE OF CONTENTS

PRELIMINARY EXAMINATION................................................................................................. 3

GENERAL DESCRIPTION ........................................................................................................ 3

SPECIFICATIONS ................................................................................................................... 6

PRINCIPLE OF OPERATION .................................................................................................... 7

FUNCTIONAL AND PHYSICAL DESCRIPTION............................................................................. 8

TITRATOR STARTUP ........................................................................................................... 10

SETUP CONFIGURATION MENU .......................................................................................... 11

ELECTRODE PREPARATION .................................................................................................. 15

ELECTRODE CALIBRATION PROCEDURE................................................................................. 16

pH BUFFER TEMPERATURE DEPENDENCE............................................................................ 20

TITRANT PREPARATION ...................................................................................................... 20

PUMP TUBE INSTALLATION................................................................................................. 21

PURGE .............................................................................................................................. 21

PUMP CALIBRATION PROCEDURE ........................................................................................ 23

TITRATION PROCEDURE ..................................................................................................... 25

pH MEASUREMENT ............................................................................................................ 30

TEMPERATURE CALIBRATION PROCEDURE (for technical personnel only) ............................... 34

TROUBLESHOOTING GUIDE ................................................................................................ 36

ELECTRODE CONDITIONING & MAINTENANCE ...................................................................... 37

ACCESSORIES .....................................................................................................................38

WARRANTY........................................................................................................................39

All rights are reserved. Reproduction in whole or in part is prohibited without the written consent of the copyright owner, Hanna Instruments Inc., Woonsocket, Rhode Island, 02895, USA.

PRELIMINARY EXAMINATION

Please examine this product carefully. Make sure that the instrument is not damaged. If any damage occurred during shipment, please notify your Dealer.

Each HI 84442 minititrator is supplied complete with:

• HI 1131B pH electrode

• HI 7071S Filling solution (30 mL)

• HI 7662-M Temperature probe

• HI 84442-50 Titrant Stock solution (100 mL) (must be diluted before use)

• HI 84442-55 Pump calibration solution (100 mL)

• HI 7061M Cleaning solution (230 mL)

• HI 7004M pH 4.01 buffer solution (230 mL)

• HI 70083M pH 8.30 buffer solution (230 mL)

• HI 7010M pH 10.01 buffer solution (230 mL)

• Two 100 mL beakers

• 100 mL white bottle

• Tube set with dispensing tip

• Stir bars (medium 2 pcs.)

• 12 Vdc power adapter

• Instruction manual

Notes:• The titrant used during titrations is obtained from HI 84442-50 Titrant Stock Solution

by dilution in 1:10 ratio (v/v) (see the Titrant Preparation procedure)

• Save all packing material until you are sure that the instrument works correctly. Any defective item must be returned in its original packing.

GENERAL DESCRIPTION

The HI 84442 is an easy to use microprocessor-based automatic minititrator and pH meter designed for rapid and accurate analysis of total very low alkalinity in water. By eliminating subjective factors including color indicators, errors in mathematical calculations or erratic titrant additions from the measurement, the HI 84442 makes Total Titratable alkalinity analysis precisely. This will quickly become a valuable alkalinity analysis tool of waters.

The instrument benefits from Hanna’s many years of experience as manufacturer of quality analytical instruments. A clear and well-designed user interface makes the instrument intuitive and simple to use. A dedicated HELP key aids in set-up, calibration, status and troubleshooting.

By simply pressing the START key, the HI 84442 automatically starts pump operation and titrates the sample to the end point. The HI 84442 has a simple and accurate peristaltic pump to ensure the best accuracy and repeatability. By performing pump calibration with the Hanna standard provided,

the instrument accuracy is assured. The instrument employs a powerful and effective built-in algorithm to analyze the pH response to

determine the exact pH endpoint, then uses this to make the necessary calculations. The Titratable Alkalinity determination is instantaneously displayed in selected measurement units on the large dot matrix display. The instrument is ready for the next analysis immediately.

Other features:

• Log on demand up to 100 samples (50 for pH measurement; 50 for titration results)

• GLP feature, to view last calibration data for pH electrode and pump

MEASUREMENT SIGNIFICANCE

Water alkalinity is expression of a waters acid-neutralizing capacity and it is determined by titration with standard acid solutions. Alkalinity is an important parameter for control and treatment of potable and wastewaters, because it indicates the water buffering capacity (ability to resist at pH change, primarily because of bicarbonate/ carbonate content). A low water alkalinity signifies that the water is susceptible to pH change and high alkalinity indicates that water is able to resist a major change of pH. Alkalinity can be used to estimate water hardness or to determine water corrosive capacity. Alkalinity of surface water, quantified by mg/L as CaCO

or meq/L, may be caused by carbonate,

bicarbonate, hydroxide, phosphates, borates, silicates or organic acids salts. Conventionally, the water alkalinity is approximated as sum of components. Three types of alkalinities exist together to form total alkalinity:

TA = OH

+ CO

2¯

+ HCO

OH¯ – hydroxide alkalinity

2¯

– carbonate alkalinity

– bicarbonate alkalinity

HCO

TA – total alkalinity Total alkalinity of water is determined by titration with an acid solution at fixed 4.5 pH value.

Potentiometric end point detection using a pH electrode is more objective than using visual end point determinations with color changing indicators. The HI 84442 minititrator is a potentiometric titrator. The instrument also can be used as a pH meter. The volume of titrant dispensed necessary to reach the end point is then used to calculate the water alkalinity expressed in mg/L as CaCO meq/L as CaCO3.

Interferences:

• dissolved gases, lost or gained during samples storage or transport can modify the

alkalinity of the samples;

• presence in the samples of the: precipitates, solid suspensions, oils, soaps can coat a pH

electrode;

To eliminate or diminish the interference effects, it is recommended:

• to protect the samples against the atmospheric action (store in an airtight vessel);

• to avoid vigorous shaking or mixing: stir gently;

• maintenance of the pH electrode (see section Electrode Conditioning and Maintenance)

SPECIFICATIONS

Titrator Range Titratable alkalinity:

mg/L : 3.00 - 10.00 mg/L as CaCO meq/L : 0.06 - 0.20 meq/L as CaCO

Resolution Titratable alkalinity:

0.01 mg/L

0.01 meq/L Accuracy 5% of reading Titration method Acid-base titration Principle End point titration: 4.50 pH Pump debit 0.5 mL/min Stirring speed 700 rpm Log data Up to 50 samples

pH meter pH meter -2.0 to 16.0 pH / -2.00 to 16.00 pH

pH Resolution: 0.1 pH / 0.01 pH pH Accuracy: ± 0.01 pH pH Calibration: 1, 2 or 3 calibration points;

3 available buffers (4.01; 8.30; 10.01) Temperature manual or automatic from compensation: -20 to 120 °C (-4 to 248 °F) Log data Up to 50 samples

Temperature Range -20.0 to 120.0 °C (-4.0 to 248.0 °F)

Resolution 0.1 °C Accuracy ±0.4 °C without probe error

Electrode HI 1131B (included) Temperature Probe HI 7662-M (included) Environment 0 to 50 °C (32 to 122 °F); max 95% RH non-condensing Power supply 12 Vdc power adapter Dimensions 208 × 214 × 163 mm (8.2×8.4×6.4”) (with beaker) Weight 2200 g (77 oz.)

REQUIRED REAGENTS Code Description Quantity/Test HI 84442 - 50 Titrant 1 mL HI 84442 - 55 Pump Calibration Solution 1 mL

PRINCIPLE OF OPERATION

Water alkalinity determination is performed by titration with acid reagent to pH end point. Alkalinity is expressed as:

• Total alkalinity determination by titration at 4.5 pH (following the reactions): If sample ph > 8.3 pH, then:

2HO

+ H2SO4 → 2H2O + SO

2¯

2CO

+ H2SO4 → 2HCO3 + SO

Otherwise:

+ H2SO4 → 2H2CO3 + SO

2HCO

It is important that the samples are protected against atmospheric factors (store them in sealed bottles that are completely filled) and avoid vigorous shaking, mixing and long exposure to air. The HI 84442 minititrator is designed to determine the potentiometric titration in a very low range (mg/mL as CaCO3). HI 84442-55 is used for pump calibration. Titratable Alkalinity in waters, as performed on the HI 84442 minititrator, utilizes a simple sample preparation, a high quality peristaltic dosing pump for titrant, potentiometric endpoint detector and instantaneaous computations. To maintain the high precision of the titrator, a simple pump calibration procedure is required. The calibration involves the analysis of a known volume of a known solution (standard provided) and compensate for changes in pump dosing that may occur due to many factors including tube stretching or aging. This procedure should be performed regularly.

2¯

Note: To ensure the titrant concentration stability, the HI 84442-50 titrant stock solution is 10

times more concentrated than used during titrations. Pay attention to dilute titrant in 1:10 ratio (v/v) before use.

FUNCTIONAL AND PHYSICAL DESCRIPTION

OVERHEAD VIEW

1. Titrant bottle

2. Graphic LCD

3. Keypad

4. Dedicated guide tube for Temperature Probe

5. Electrode holder

6. Dedicated guide tube for titrant tip

7. Peristaltic pump tube

FRONT VIEW

REAR VIEW

8. Temperature probe

9. pH Electrode

10. Beaker

11. BNC electrode connector

12. Temperature probe socket

13. Power switch

14. Power adapter connector

15. Peristaltic pump

KEYPAD FUNCTION AND INDICATORS

ESC - used to leave the current screen and to return either to the previous screen or to the

main screen. When pressed while modifying a parameter within the SETUP menu, exits parameter without changing it.

- used to modify the parameters’ values, to scroll the information displayed while viewing a help or to move between the options from the instrument’s SETUP

HELP - used to access/leave the instrument’s contextual help MENU - used to enter SETUP, Recall or GLP selection menu, while instrument is in pH or

Titration main screen

STIR - used to start/stop the stirrer. Note: The stirer starts automatically during pump calibration and titration and cannot be

stopped by pressing STIR key.

GUIDE TO INDICATORS

During the instrument’s operation information is displayed on the LCD. Displayed icons:

Unstable reading. Stirrer on.

Pump running.

Parameter can be changed.

1. Current time and instrument mode information (pH meter or Titrator)

2. pH electrode condition information

3. Main reading information

4. Instrument status information

5. Functional key area

6. Indicates that the displayed value can be changed using ARROW keys

7. Temperature value (

8. pH temperature compensation mode (Manual or Automatic)

9. Stirrer and reading status area

PERISTALTIC PUMP

Peristaltic pumps are self priming. Liquid never contacts the pump components. The titrant tubing is pressed along the rotating rollers of the pump. The rollers compress the tubing, driving the titrant to the dispensing tip.

°C, °F)

TITRATOR STARTUP

This is a general outline of the steps required to make a titration. The following sections expand upon each section.

• Place the instrument on a flat table. Do not place the instrument in direct sun light.

• Connect the power adapter to the instrument.

• Turn the instrument ON using the power switch from the rear panel of the instrument.

• Set up the instrument. See the “Setup Configuration Menu” section for details.

• Connect the pH sensor and temperature probe to the instrument.

• Calibrate the pH electrode. At least a single point calibration is necessary for titration.

• Place the peristaltic pump tube on the pump (inlet tube is connected with the reagent bottle, outlet tube is connected with the dosing tip). See the “Pump Tube Replacement” section for the procedure.

• Remove the reagent bottle cap and replace the bottle cap with the tubes. Place the reagent bottle in the appropriate place on the titrator top.

• Purge the titrant.

• Calibrate the pump.

• Prepare the sample.

• Run a titration and log sample results.

SETUP CONFIGURATION MENU

The titrator’s setup configuration menu may be accessed from the pH or titration screens by pressing the MENU key, then Setup.

A list of setup parameters will be displayed with currently configured setting. While in the setup menu it is possible to modify the instrument’s operation parameters. The

ARROW keys permit the user to scroll the setup parameters. Press HELP to view the contextual help. Press ESC to return to the main screen.

Concentration unit

Options: mg/L, meq/L.

Press the corresponding function key to change the option.

Calibration timeout

Options: Disabled or 1 to 7 days.

This option is used to set the number of days before the pH calibration expired warning message is flagged.

Press Modify to access the calibration timeout value modify parameter.

pH resolution

Use the ARROW keys in order to increase/decrease the value.

Press Accept to confirm or ESC to return to the setup menu without saving the new value.

Options: 0.1, 0.01. Press the displayed function key in order to change

the pH resolution.

Temperature unit

Backlight

Options: °C, °F.

Press the function key in order to change the temperature unit.

Options: 0 to 8. Press Modify to access the backlight level.

Contrast

Use the ARROW keys or increase/decrease the displayed constrast.

Press Accept to confirm or ESC to return to the setup menu.

Option: 0 to 20. This option is used to set the display’s contrast. Press Modify to change the display’s contrast.

Use the ARROW keys or / in order to increase/decrease the value.

Press Accept to confirm the value or ESC to return to the setup menu.

/ in order to

+ 28 hidden pages