Staionary source emission Determination of fluoride -Ion selective electrode method

Release Time

2023-12-18 00:00


Ion selective electrode method of fluoride ion is widely universities, environmental protection, medicine, food, sanitation, geological prospecting, metallurgy, ocean exploration and other fields measurements.

 

1. Standard Reference

 

      METHOD 13B - Determination of Total Fluoride Emissions From Stationary Sources(Speicfic ion method)

 

2. The Principle

 

      Gaseous and particulate F are withdrawn isokinetically from the source and collected in water and on a filter. The total F is then determined by the specific ion electrode method.

 

3. The Reagents

 

      Total Ionic Strength Adjustment Buffer (TISAB). Place approximately 500 ml of water in a 1-liter beaker. Add 57 ml of glacial acetic acid, 58 g of sodium chloride, and 4 g of cyclohexylene dinitrilo tetraacetic acid. Stir to dissolve. Place the beaker in a water bath and cool to 20°C (68°F). Slowly add 5 M NaOH to the solution, measuring the pH continuously with a calibrated pH/reference electrode pair, until the pH is 5.3. Pour into a 1-liter volumetric flask, and dilute to volume with deionized, distilled water. Commercially prepared TISAB may be substituted for the above.

 

      Fluoride Standard Solution, 0.1 M. Oven dry approximately 10 g of sodium fluoride (NaF) for a minimum of 2 hours at 110°C (230°F), and store in a desiccator. Then add 4.2 g of NaF to a 1-liter volumetric flask, and add enough water to dissolve. Dilute to volume with water.

 

4. The Calibration

 

   Analyze the standards going from dilute to concentrated standards. A straight-line calibration curve will be obtained, with nominal concentrations of 10−4 , 10−3, 10−2 , 10−1fluoride molarity on the log axis plotted versus electrode potential (in mV) on the linear scale. Some electrodes may be slightly nonlinear between 10−5 and 10−4 M. If this occurs, use additional standards between these two concentrations.

 

5. The Measurement

 

Insert the fluoride and reference electrodes into the solution. When a steady millivolt reading is obtained, record it. This may take several minutes. Determine concentration from the calibration curve. Between electrode measurements, rinse the electrode with water.

It is suggested to use the Auto-reading. The measurement reached the balance, and the meter locked the reading result. The meter offers "Fast", "Medium", "Strict" and "Custom" four options for endpoint detection conditions.

 

 

                                                                                                      Reading Parameters Settings

Stability Type

pH

pX/Ion concentration

Fast

Stable time

4s

4s

Fluctuation

0.6mV

0.3mV

Medium

Stable time

6s

8s

Fluctuation

0.1mV

0.08mV

Strict

Stable time

8s

12s

Fluctuation

 0.03mV

0.03mV

Custom

(Recommended value)

Stable time

1 to 30s

1 to 30s

Fluctuation

0.03~1mV

0.03~1mV

 

 

6. Recommended Configuration

I500T pH/Ion Meter

I500T pH/Ion meter is a newly designed laboratory high-precision intelligent analytical instrument. It has powerful calibration, measurement and automatic compensation functions. It has high measurement accuracy and is simple and convenient to use. At the same time, the instrument has measurement control and data traceability functions such as method management, calibration reminder and mandatory calibration, standard solution verification and mandatory verification, comprehensive data management, and GMP working mode, which can realize the whole process traceability from the measurement process to the measurement results.

  • Color High contrast LCD touchscreen, 7.0 inches.
  • Intelligent operation system provides features including user management, calibration management, method management, data management and etc.
  • Multi-reading feature allows auto-read, timed-read and continuous-read. 
  • Automatic/Manual temperature compensation ensures accurate results.
  • Data Storage 1000 sets for each parameter (GLP-compliant).
  • Data analysis feature helps user review, compare and recalculate results.
  • Support for USB or RS-232 communication.
  • Reset feature automatically resumes all settings back to factory default options.
  • IP54 waterproof.

 

Model

I500T

Parameters

pH/ISE/Temp.(mV/ORP/pX)

pX

Range

-2.000 to 20.000 pX

Resolution

0.1, 0.01, 0.001 pX

Accuracy

±0.002 pX

Calibration Points

Up to 6

ISE

Range

1.000e-9 to 9.999e+9

Units

mol/L, mmol/L, g/L, mg/L, μg/L, ppm, ppb

Resolution

Up to 4 significant digits

Accuracy

±0.3%

Calibration Points

Up to 6

Temperature

Range

-10 to 135 ºC, 14 to 275 ºF

Unit

ºC, ºF

Resolution

0.1

Accuracy

±0.1ºC

 

 

972101 Combined Ion Selective Electrode

 

                                                                                                             

Model

972101

Species

Fluoride (F-)

Name

Combined Ion Selective Electrode

Measuring range (mol/L)

1.0×10-6M~saturation

Membrane

Crystalline state membrane

Body

Polypropylene (PP)

Dimensions

Φ12×120 mm

Working Temp.

0~80 ℃

Connector

BNC(Q9)

Junction

Separate ring grinding mouth glass

Reference Electrolyte

S

Reference Type

ClickOK Ref.

Working pH

5-7

 

PF-202-C/PF-202 Combined Ion Selective Electrode

  • The  Ion Selective Electrodes combines the reference electrode.

                                                                                                                                               

Model

PF-202-C

PF-202

Species

Fluoride (F-)

Fluoride (F-)

Name

Combined Ion Selective Electrode

Combined Ion Selective Electrode

Measuring range (mol/L)

1×10-6~0.1 M

1×10-6~0.1 M

Membrane

Crystalline state membrane

Crystalline state membrane

Body

Plastic

Plastic

Dimensions

Φ12×120 mm

Φ12×120 mm

Working Temp.

5~45 ℃

5~60 ℃

Connector

BNC(Q9)

BNC(Q9)

Working pH

4-8

PF4-8-202

PCI-1-01 Ion selective electrode

The Ion Selective Electrodes (ISE) need cooperate with reference electrode, such as 232-01 reference electrode.

                                                                                                                                

Model

PF-2-01

PF-3-01

Species

Fluoride (F-)

Fluoride (F-)

Name

Ion selective electrode

Ion selective electrode

Measuring range (mol/L)

1×10-6~0.1 M

1×10-6~0.1 M

Membrane

Crystalline state membrane

Crystalline state membrane

Body

Plastic

Glass

Dimensions

Φ12×120 mm

Φ12×120 mm

Working Temp.

5~45 ℃

5~45 ℃

Connector

BNC(Q9)

BNC(Q9)

Working pH

4-8

4-8

Recommend Reference electrode

232-01

232-01