D-810

Easy C1 Titrator Operation Maintenance and Qualification

Section D — Laboratory Operations and Specifications Revision 0 14 pages

Original Document

Scanned document (image-only PDF)

Extracted Text

Searchable text extracted from PDF

1.0 Purpose 
 
 This procedure provides guidelines for general use, maintenance, and performance qualification
 
 of the Mettler Toledo Easy Cl titrator. 
 
 2.0 Scope 
 
 This procedure applies to the Mettler Toledo Easy Cl titrator in the QC laboratory.
 
 3.0 Responsibility 
 
 3.1 It is the responsibility of QC chemists to follow this procedure. 
 
 3,2 It is the responsibility of QC Laboratory Management to ensure that this procedure is
 being followed. 
 
 3.3 It is the responsibility of Metrology and/or Analytical Development to perform
 
 preventative maintenance and performance qualification of the Easy Cl titrator.
 
 3.4 It is the responsibility of QC Laboratory Management and/or Analytical Development
 personnel to keep this procedure aligned with current practices. 
 
 4.0 Definitions 
 
 4.1 QC — Quality Control 
 
 4.2 AD — Analytical Development 
 
 4.3 H20 — Deionized Water 
 
 4.4 NaCl — Sodium Chloride 
 
 4.5 KNOs — Potassium Nitrate 
 
 4.6 HNOs — Nitric Acid 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page 2 of14
 
 4.7 AgNO; -— Silver Nitrate 
 
 48 VEQP -— Volume of titrant consumed to reach the equivalence point 
 
 5.0 References 
 
 5.1 EasyPlusTM Titration Operating Instructions 
 
 5.2 USP <541> Titrimetry 
 
 a3 D-603, SOP, Chemical Waste Disposal 
 
 5.4 General European OMCL Network (GEON) Quality Management Document, 
 
 PA/PH/OMCL (07) 108 R11, Qualification of Equipment Annex 5: Qualification of
 Automatic Titrators. 
 
 5.5 PRTCL-23-0049, Protocol, Installation Qualification and Operational Qualification of
 
 the Mettler Toledo Easy Cl Titrator 
 
 5.6 RPT-23-0040, Report, Installation Qualification and Operational Qualification of the
 Mettler Toledo Easy Cl Titrator 
 
 6.0 Safety Precautions 
 
 6.1 AgNO3 solution may cause skin and/or eye irritation. Personal protective equipment
 including gloves and eye protection is recommended. 
 
 7.0 Waste Handling and Disposal 
 
 Tal AgNO; solution is toxic to aquatic life. Store AgNO: waste separate from other waste
 streams. Waste handling and disposal procedures are outlined in SOP D-603.
 
 8.0 Silver Ring Sensor 
 
 8.1 The Easy Cl titrator should be used with an EM45-BNC Silver Ring Sensor (Mettler
 Toledo Part # 30043107 or equivalent). 
 
 8.1.1 The sensor should be filled to approximately 1 cm below the fill opening with 0.1
 
 N KNOs; filling solution. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page3of14
 
 8.1.2 Before use, remove the plug from the fill opening. 
 
 8.1.3 The electrolyte solution inside of the sensor should always be above the level of
 
 the sample solution to keep the sample solution from entering the sensor.
 
 8.1.4 To store the sensor: fill the storing cup about half way with 0.1 N KNOs filling
 
 solution, place the storing cup on the sensor ensuring that the tip of the sensor is
 submerged in filling solution, then close the filling plug. Do not allow the tip of
 
 the sensor to dry out! 
 
 8.1.5 If the electrode dries out, immerse the tip in H2O for at least 15 min to dissolve
 
 any KNO3 crystals that may have precipitated in or on the frit.
 
 9.0 Reagents 
 
 9.1 Sodium chloride traceable reference standard 
 
 9.2 0.1 M AgNO; Titrant 
 
 9.2.1. Silver nitrate is sensitive to light and air. Store protected from light in a tightly
 
 closed container. 
 
 9.2.2 Use commercially prepared titrant, or prepare as outlined below.
 
 9.2.2.1 Accurately weigh and transfer 16.987 g of AgNO; into a 1000-mL
 low-actinic (red) or foil wrapped volumetric flask. 
 
 9.2.2.2 Dissolve in and dilute to volume using H20. 
 
 9.3 2M HNOs3 
 9.3.1 Transfer 175 mL of H20 to a 250-mL plastic bottle. 
 
 9.3.2 Carefully add 25 mL of concentrated (~70%) HNO3. 
 
 9.3.3. Mix well. 
 
 9.4 1 MKNOs; filling solution. 
 9.4.1 Use commercially prepared filling solution, or prepare as outlined below.
 
 9.4.2 Accurately weigh and transfer about 10.1 g of KNO3 into a suitable container.
 
 
 

[SOP 

 Standard Operating Procedure SOP No Rev 
 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 Page 4 of 14
 
 9.4.3. Add 100 mL H20. 
 
 9.4.4 Mix to dissolve. 
 
 10.0 Rinsing the Burette 
 
 10.1 The burette should be rinsed with fresh titrant daily before first use.
 
 10.2 Turn on by pressing the power button on front of the instrument. The instrument is ready
 
 when the status LED stops blinking. 
 
 10.3 The following icons are displayed on the main menu: Titration, Burette, Stirrer, Titrant,
 Sensor, and Measure. To reach home from another screen, select Home fa.
 
 10.4 From the home screen, select Burette > Properties. 
 
 10.5 Ensure that the 20 mL burette is selected. 
 
 10.6 Place a waste collection vessel at the end of the titration tube. 
 
 10.7 Select Actions > Rinse > 1 cycle, and click the green start button.
 
 10.8 Wait for the burette rinse to complete. 
 
 10.9 Check for air in the burette and tubing. If air remains in the burette and/or tubing, repeat
 the burette rinse. 
 
 10.10 After all air has been evacuated, remove the waste collection vessel.
 
 11.0 Perform a Titer Determination 
 
 11.1 A titer determination should be performed every seven days. 
 
 112 From the home screen, select Titrant > Properties. 
 
 11.3 Ensure the following settings are correct: 
 
 11.3.1 Titrant = AgNO3 
 
 11.3.2 Nominal concentration = 0.1 mol/L 
 
 11.4 Select Determination. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 Page 5 of 14
 
 11.5 Ensure the following settings are correct: 
 
 11.5.1 Relevant EQP = 1 
 
 11.5.2 Stir speed = Medium 
 
 11.5.3 Predispense = 0 mL 
 
 11.5.4 Control = Normal 
 
 11.5.5 Prestir duration = 60 sec 
 
 11.5.6 Wait time = 0 sec 
 
 11.5.7. Primary Standard = NaCl 
 
 11.5.8 Purity = (enter the reference standard purity in units of percent)
 
 11.5.9 Sample size entry = Variable 
 
 11.5.10 Equivalence number = 1 
 
 11.5.11 Multiple determination = Yes. 
 
 11.5.12 Printout = Long 
 
 11.5.13 Export = None 
 
 11.6 Weigh about 60 mg of sodium chloride reference standard directly into a titration vessel.
 
 11.7. Add 50 mL H20. 
 
 11.8 Add 1.0 mL of 2M HNOs. 
 
 11.9 Adda stir bar. 
 
 11.10 Place the titration vessel on the stirrer, and lower the sensor and titration tube into the
 
 standard solution. 
 
 11.11 Begin the titer determination by pressing Start . 
 
 11.12 After the titer determination has been completed, the results will be printed.
 
 11.13 Remove the titration vessel from the stand. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 Page 6 of 14
 
 11.14 Rinse the sensor and titration tube thoroughly with H20. 
 
 11.15 Repeat steps 11.8 — 11.16 for a total of three titer determinations.
 
 11.16 After three titer determinations have been complete, select “* to end.
 
 11.17. The titer statistics will print, and the new titer value will be automatically saved.
 
 11.18 Acceptance criteria = NMT 1.0% RSD. 
 
 12.0 Performing a Sample Determination 
 
 12.1 On the main screen, select Titration and verify that the following parameters are chosen:
 
 12.1.1 Relevant EQP = 1 
 
 12.1.2 Titration type = Direct 
 
 12.1.3. Control = Normal 
 
 12.1.4 Sample ID = Variable 
 
 12.1.5 Stir speed = Medium 
 
 12.1.6 Pre-stir duration = 300 sec (longer time may be required for some samples)
 
 12.1.7 Pre-dispense = 0 mL 
 
 12.1.8 Wait time = 0 sec 
 
 12.1.9 Sample size entry = Variable weight 
 
 12.1.10 Calculation = Content (mg/g or % depending on sample specification)
 
 12.1.11 Molecular weight = 35.453 
 
 12.1.12 Equivalence number = 1 
 
 12.1.13 Multiple determination = No 
 
 12.1.14 Printout = Long 
 
 12.1.15 Export = None 
 
 12.2 Place astir bar into a titration vessel. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 Page 7 of 14
 
 12.3 Weigh an amount of sample containing 15 - 64 mg of chloride into the titration vessel.
 
 This should result in a volume of titrant delivered (VEQP) during titration between 4 mL
 
 and 20 mL. 
 
 12.3.1 Ifthe VEQP for the titrationis less than 4 mL, then a larger sample size must be
 used. 
 
 12.3.2 Ifthe VEQP for the titration is greater than 20 mL, then a smaller sample size
 
 must be used. 
 
 12.4 Add 50 mL of H20. 
 
 12.5 Add 1.0 mL of2M HNOs. 
 
 12.6 Place the titration vessel on the stirrer, and lower the sensor and titration tube into the
 
 sample solution. 
 
 Begin the sample determination by pressing Start ©. 
 LZ 
 12.8 Follow the progress of the titration on the screen. 
 
 12.9 After the determination is complete, a report will be printed. 
 
 12.10 Remove the titration vessel from the stand. 
 
 12.11 Rinse the sensor and titration tube thoroughly with H20. 
 
 13.0 Daily Cleaning 
 
 13.1 Thoroughly rinse the sensor (probe) and titration tube with water. Use a moist tissue to
 remove any remaining residue. 
 
 13.2 To store the sensor: Fill the storing cup about half way with 0.1 N KNOs filling solution.
 
 Ensure that the filling plug is open. Place the filling cup on the sensor ensuring that the
 tip of the sensor is submerged in filling solution, and close the filling plug. Do not allow
 
 the tip of the sensor to dry out! 
 
 13.3 Clean the instrument housing using a tissue moistened with H2O or mild detergent
 solution. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No Rev 
 Page 8 of 14 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 
 14.0 Preventative Maintenance 
 
 14.1 Preventative maintenance should be performed every six months. 
 
 14.2 Clean the instrument housing using a tissue moistened with H2O or a mild detergent
 
 solution. 
 
 14.3 Rinse tubes, valve, and burette. 
 
 14.3.1 Remove the green tube from the beaker and place it in a waste container.
 
 14.3.2 Unscrew the blue tube from the bottle and place it in an empty container.
 
 14.3.3. To empty the tubes, run the function Burette > Rinse until all tubes are empty.
 
 14.3.4 Place the blue tube in a bottle with H20. 
 
 14.3.5 Run the function Burette > Rinse until the tubes are rinsed.
 
 14.3.6 Place the blue tube in a bottle with ethanol. 
 
 14.3.7. Run the function Burette > Rinse until the tubes are rinsed.
 
 14.3.8 Place the blue tube in an empty bottle. 
 
 14.3.9 Run the function Burette > Rinse until the tubes are empty.
 
 
 

[SOP 

 Standard Operating Procedure SOP No 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 Page 9 of 14
 
 14.4 Disassemble the burette. 
 
 14.4.1 Do not pull the piston out of the glass cylinder! 
 Reinserting the piston into the glass cylinder will 
 
 damage the o-rings. 
 
 14.4.2 Rinse and empty the burette, valve and tubes as outline 
 above. 
 
 14.4.3 Disconnect the instrument from the power supply. 
 
 14.4.4 Disconnect the red tube from the top of the burette cap 
 (3) and clean the connections with a tissue. 
 
 14.4.5 Disconnect the cap nut (2). 
 
 14.4.6 Lift off the burette cover (1) including the cap nut (2). 
 
 14.4.7 Carefully lift the glass cylinder (4), until you are able 
 
 to slide the burette from the piston rod (6). 
 
 14.4.8 Remove the burette cap (3) and empty the burette into 
 a waste bottle. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page 10 of 14
 
 14.4.9 Replace the burette if the piston leaks, if the glass eS 
 
 cylinder is badly scored at the edge, or if crystals have 7aS e.
 formed between the seals of the piston. | | 
 
 14.5 Clean the burette parts. hal 2 
 
 14.5.1 Never place O-rings in organic solvents. We 
 
 14.5.2 Never attempt to remove any crystals in the cylinder by Saae 3
 scratching with a hard object. 
 4 
 
 14.5.3 Never put the parts in a drying oven with a temperature i 
 higher than 40°C. 
 
 14.5.4 Rinse cylinder, valve, and tubes first with H2O ad then with
 
 ethanol. 
 
 14.5.5 Dry the parts with oil-free compressed air or nitrogen. 
 
 14.6 Clean the burette compartment 
 
 14.6.1 Disconnect the instrument from the power supply. 
 
 If there is liquid in the burette compartment, absorb the liquid with a cotton swab
14.6.2 or tissue.

14.6.3 Push a thin rod from the rear of the instrument (2) into the

 outlet (1) of the burette compartment. 
 14.6.4 Pull the thin rod out of the outlet. 
 
 14.6.5 If the thin rod has pushed dirt into the valve compartment,
 take the dirt out with tweezers. 
 
 14.7. Assemble the burette 
 
 14.7.1 Disconnect the instrument from the power supply. 
 
 14.7.2 Place the burette cap (3) onto the glass cylinder (4). 
 
 14.7.3 Slide the glass cylinder (4) onto the piston rod (6). 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page 11 of 14
 
 14.7.4 Carefully press the glass cylinder (4) down until it touches the housing of the
 
 instrument. 
 
 14.7.5 Place the burette cover (1) over the glass cylinder. 
 
 14.7.6 Place the cap nut (2) over the burette cover (1). 
 
 14.7.7. Screw the cap nut (2) onto the housing of the instrument and tighten it.
 
 14.7.8 Screw one of the connectors of the red tube into the burette cap (3) and tighten
 
 it. 
 
 14.7.9 Screw the other connector of the red tube into the red opening of the valve and
 
 tighten it. 
 14.7.10 Make sure that all tubes are firmly connected and all cap nuts tightened.
 
 14.8 Remove the valve. 
 
 14.8.1 The burette, valve and tubes should be 
 rinsed and emptied as outlined above 
 
 prior to removing the valve. 
 
 14.8.2 Disconnect the instrument from the 
 
 power supply. 
 14.8.3 Unscrew all tube connectors (2) from the 5 
 
 valve and clean the tube connectors with 
 
 a tissue. 
 
 14.8.4 Check that all tube connectors are removed. 
 
 14.8.5 Unscrew the cap nut (1) holding the valve. 
 
 14.8.6 Remove the valve (3). 
 
 14.9 Clean the valve. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 Page 12 of 14
 
 14.9.1 Place the valve for 30 minutes, or until 
 
 the residue is dissolved, in deionized 
 
 water or in ethanol. 
 
 14.9.2 Take the valve out and leave it to air-dry. 
 
 14.10 Clean out the valve compartment. 
 
 14.10.1 The valve should be removed as 
 described above prior to cleaning the 
 
 valve compartment. 
 
 14.10.2 Disconnect the instrument from the 
 
 power supply. 
 
 14.10.3 If there is liquid in the valve [ 
 compartment, absorb the liquid with a 
 
 swab or tissue. [ 
 
 14.10.4 Push a thin rod from the rear of the instrument into the outlet (1) of the valve
 
 compartment. 
 14.10.5 Check that the end of the thin rod reaches the opening of the outlet (1) in the
 
 valve compartment. 
 
 14.10.6 Pull the thin rod out of the outlet. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page 13 of 14
 
 14.10.7 If the thin rod has pushed dirt into the 
 
 valve compartment, take the dirt out with 
 
 tweezers. 
 
 14.11 Install the valve. 
 
 14.11.1 Make sure that the guide (1) is 
 perpendicular to the driver bar (2). 
 
 14.11.2 Orient the valve so the guide (4) points 
 
 toward the burette. 
 
 14.11.3 Insert the valve (3). 
 
 14.11.4 Screw the cap nut (1) on the instrument 
 
 and tighten it. 
 
 14.12 Replace the siphon tip. 
 
 14.12.1 Place a waste bottle next to the instrument. 
 
 14.12.2 Pull the green tube from the beaker and place it in a waste container.
 
 14.12.3 Unscrew the green tube from the valve and empty the tube into the waste
 
 container. 
 % RS 
 14.12.4 Pull the siphon tip (2) with tweezers out of the tip of XN 1
 oo 
 the green tube (1). *BS 
 14.12.5 Push a new siphon tip (2) into the tip of the green tube Qe 2
 
 (1). 
 
 15.0 Performance Qualification 
 
 15.1 Performance Qualification shall be performed annually. 
 
 15.2 Prior to performance qualification, perform all preventative maintenance outlined above.
 
 15.3 Performance qualification shall be performed using a freshly opened bottle of commercial
 
 titrant. 
 
 
 

[SOP 

 Standard Operating Procedure SOP No | Rev 
 Easy Cl Titrator Operation Maintenance and Qualification D-810 0 | Page 14 of 14
 
 15.4 Precision 
 
 15.5 Perform 5 titer determinations using about 25 mg, 45 mg, 65 mg, 85 mg, and 105 mg of
 sodium chloride reference standard for the 5 determinations. 
 
 15.5.1. The instrument will print a summary including the mean titer and %RSD for the
 
 replicate determiantions. 
 
 15.5.2 Acceptance Criteria: NMT 1.0 % RSD. 
 
 15:6 Linearity 
 
 15.6.1 Using the data obtained for evaluation of Precision, create a plot of mL titrant
 
 delivered vs. reference standard weight. 
 
 15.6.2 Determine a linear regression using the method of least-squares.
 
 15.6.3 Acceptance criteria: R? is NLT 0.998. 
 
 13.7 Accuracy 
 
 15.7.1 Using the data obtained for evaluation of Precision, calculate the average (mean)
 titer value. 
 
 15.7.2 Calculate the Accuracy: 
 
 titer, 
 Accuracy (%) = ——————— x 100 
 ttteTtneoretical 
 
 15.7.3. Acceptance Criteria: 99% - 101% 
 
 16.0 Consumables List 
 
16.1 Beakers 100mL polypropylene (120 pcs.) Mettler Toledo Part # 51109388 or equivalent.

 16.2 Sensor EM45-BNC Mettler Toledo Part # 30043107. 
 
 16.3 Siphon Tips (5 pes.) Mettler Toledo Part # 23240. 
 
 17.0 Revision History 

| Rev | Date | Description of Changes | CCR # | By |
|-----|----------|------------------------|-------|----|
| 0 | 07/12/23 | New N/A S. Sassman | - | - |