HI 4110 FLUORIDE COMBINATION FLUORIDE HI 4010 Instruction Manual HI 4010 HI 4110 Half-cell Combination Fluoride Ion Selective Electrode 1
HI 4010 Fluoride Half-cell HI 4110 Fluoride Combination Electrode I. Introduction: The Hanna HI 4010 and HI 4110 are ion selective electrodes designed for the measurement of fluoride ions in aqueous solutions. The HI 4010 is a solid state half-cell sensor that requires a separate reference. The HI 4110 is a combination ion selective electrode. IIII. Specifications Type: Solid State electrode with a Lanthanum Fluoride crystal membrane. Fluoride (F-) Saturated to 1X 10-6M Saturated to 0.
III. Theory of Operation Operation:: The HI 4010 or HI 4110 fluoride electrodes are potentiometric devices used for the rapid determination of free fluoride ions in water, soft drinks, wine, emulsified foods, and plating and pickling acids. The electrode functions as a sensor or ionic conductor. The HI 4010 requires a separate reference electrode to complete its electrolytic circuit. The HI 4110 has a reference electrode incorporated in its design.
IV.
V. Equipment required required: • Hanna HI 5315 double junction reference electrode with HI 7075 fill solution for measurements with HI 4010. • Hanna HI 4222 pH/ISE/mV meter or other suitable ion or pH/mV meter. (Note: log/linear graph paper is useful if an ISE (ion) meter is not available. • Hanna HI 180 magnetic stirrer or equivalent with stirring bars (HI 731320). (Note: isolate beakers from stirrer motor heat by placing insulating material such as foam or cork between them).
Using volumetric pipettes and glassware make dilutions to bracket the concentration of the samples. Standards with concentrations < 10-4 M (1.9 ppm) should be prepared daily. Standards that are asterisked contain TISAB II and should be used directly with no additional TISAB II added. Samples used with these standards should have TISAB II added. To 50 parts standard or sample add 50 parts TISAB II (HI 4010-00, HI 4010-05) or to 50 parts standard or sample add 5 parts of TISAB III concentrate (HI 4010-06).
• A slightly scratched crystal may benefit from a treatment with a fluoride containing toothpaste (without baking soda). Lightly wipe the sensor tip with the mild abrasive. Rinse well with deionized and soak in a fluoride standard near measurement value. • Avoid large changes in temperature (thermal shock) as it may damage the sensor. HI 4010 • Remove protective cover from sensor tip. HI 4110 • Remove the protective plastic wrap that covers the ceramic junction before assembling sensor for the first time.
VIII. Electrode Preparation HI 4010 1. Remove protective cover from HI 4010 sensor tip. 2. Due to shipping or storage the internal solution inside the electrode may have developed an air pocket near the membrane. Gently shaking the sensor down (like the old style mercury thermometer) will place the internal solution next to the membrane. Note: when the sensor is inverted an air pocket will be seen which is normal. 3. Prepare HI 5315 reference electrode by filling outer electrolyte reservoir with HI 7075. 4.
Deionized Water Remove Parafilm Install sensing module 6. Reassemble electrode by gently pushing the inner assembly into the outer body, sliding spring down cable, and screwing cap into place. DO NOT TOUCH OR PUT PRESSURE ON LANTHANUM CRYSTAL. 7. Remove fill hole cover and o-ring on fill hole spout. 8. Using the dropper pipette provided, add a few drops of HI 7075 fill solution to the electrode, wetting the oring and rinsing out the fill solution chamber.
HI 4110 DE FLUORI TION NA COMBI 9. Holding the body of the electrode gently press upper cap with your thumb. This permits the fill solution to drain out of the body. Release cap and verify electrode returns to its original position (you may need to gently assist for this to occur). 10. Tighten the electrode cap onto the body and fill electrode body until fill solution volume is just below fill hole. 11. Position electrode in a Hanna HI 76404 electrode holder (or equivalent) and connect plug to meter. IX.
• stabilized. This value should be less than the previous noted (more negative). Determine the difference between the two-mV values. An acceptable value for this slope is -56 ± 4 mV. X. Corrective action • Verify protective cap has been removed (HI 4010). • Verify plastic film has been removed from inner stem (HI 4110 or HI 5315 electrode). • Verify electrodes are connected properly to meter and meter is powered. For HI 4110 verify sensor is screwed into the inner stem.
For HI 4110 module replacement 1. Drain the fill solution by pressing the upper cap. Rinse electrode with distilled or deionized water. Drain. 2. Unscrew upper cap and slide down cable toward connector. 3. Move spring and outer body down cable also. 4. Dry off inner stem and module with a soft tissue. 5. Hold inner stem and unscrew module and replace with a new one. (HI 4110-51). 6. Reassemble electrode (see section VIII), and refill with electrolyte.
If no fluoride complexing species are in the sample, TISAB needn’t be added at the same proportions. Add 1 parts TISAB to 100 parts sample or standard. Ionic strength will be fixed at approximately 0.02M. Attention: Always prepare samples and standards with the same ISA to volume ratio. 1) Follow sections VIII and IX to prepare sensors for measurement. 2) Follow section VI to prepare standards/solution. Standards should bracket the sample concentration.
XII. Other Measurement TTechniques echniques Known addition (for F-) An unknown concentration can be determined by adding a known amount (volume and concentration) of measured ion to a known volume of the sample. This technique is useful for very low F- concentration samples. It can use an ideal sensor slope, but actual determined slopes at the temperature of measurement should be used if known. This method is preprogrammed in the Hanna HI 4222 pH/ ISE/mV meter, which simplifies the method greatly.
Five mL acetate buffer (3.7 M HOAC/0.76M 0AC- in composition) is added to 100 mL of sample. A standard aluminum solution is first titrated with a fluoride solution to determine the endpoint value. Measurements may be automated by use of the Hanna Titrator HI 901 or titrated manually. XIII. pH The HI 4110 and HI 4010 sensors measure fluoride ions between 5 and 8 pH. XIV.
MAN4110 10/02/R3 WARRANTY Hanna Instruments Ion Selective Electrodes are warranted to be free of defects in material and workmanship for 6 months from date of purchase when used for their intended purpose and maintained according to instructions. If they fail to work when first used contact your dealer immediately. Damage due to accidents, misuse, misapplication, tampering or lack of prescribed maintenance is not covered.
