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Gaseous and particulate F⁻ are withdrawn isokinetically from the source and collected in water and on a filter.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 10−4M. 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
Fast	Fluctuation	0.6mV	0.3mV
Medium	Stable time	6s	8s
Medium	Fluctuation	0.1mV	0.08mV
Strict	Stable time	8s	12s
Strict	Fluctuation	0.03mV	0.03mV
Custom (Recommended value)	Stable time	1 to 30s	1 to 30s
Custom (Recommended value)	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