SOP FOR OPERATION AND CALIBRATION OF GAS CHROMATOGRAPHY [FID]

1.0        Objective:

             The objective of this Standard Operating Procedure is to lay down the procedure for

             operation and calibration of Gas chromatography (HP-6890)

2.0        Scope:

             This SOP covers procedure for operation and calibration of Gas chromatography

             (HP-6890)

3.0        Responsibility:

            Jr. Research Officer, Research Officer: Responsible for operation and maintenance of

               the instrument as per procedure.

Head of Department: Responsible for maintenance, timely as per   schedule.

QA Officer/QA Manager: Review the records and governing the document

4.0                  Procedure :

4.1        Ensure that the instrument is clean and free from dust. Wipe all the traces of

  solvent/water/moisture by dry cloth.

4.2

   I.     The room temperature should be maintained between 10 to 30°C and relative humidity 

            Should be maintained between 30 to 80 %

II.    Avoid direct exposure to air-blow from air conditioners.

III.    Avoid exposure to direct sunlight and vibrations.

IV.     Avoid from equipment which generates strong magnetic field.

4.3       Install properly suitable capillary column in GC oven injector & selected detector.

4.4      Open the valve of gas cylinder of Nitrogen, Hydrogen and z-Air. And checked the

    pressure & leakage. 

4.5     Open the Gas pressure valve from the distribution panel.

4.6     Check the backpressure of column.

4.7       Switch on the mains power, stabilizer, GC power & computer power.

4.8     Double click on the instrument1 (online) & instrument1 (offline) icon from the desktop;

             create new method from instrument1 (offline) and load method in instrument1 (online)

 from file menu. Apply the chromatographic condition and enter ok. And view the run

 signal window, After completion of the run, and open the instrument offline select the file 

 and] integrate the peak using integration menu, go to calibration task icon and enter the

             component name and click on ok, then print the chromatogram by clicking print option

             from file menu.

4.9     Condition the column at 280°C for 10 min. Enter the programming condition of the                        sample through micro syringe, when G.C shows ready signal.

4.10   Cool the G.C after completion of the analysis & switch it off. Shut down the computer, 

             mains power supply. Close the gas supply from the distribution panel & from cylinder.

5.0        Calibration procedure:

5.1        Calibration of Flow rate

5.1.1     Open the column oven compartment.

5.1.2     Install the properly capillary column.

5.1.3         Connect soap film flow meter to the detector port outlet with the help of Teflon or

             rubber tube.

5.1.4         Fill the pipette bulb partially with a soap solution and attach to the bottom of the flow

             meter.

5.1.5    Open the knob of carrier gas (N2) and set up proper pressure (i.e. 500 kpa or 5 Kg/cm2) in

             carrier gas pressure controller.

5.1.6    Check for leaks at each and every point of attachment using soap solution.

5.1.7    Open the knob of carrier gas flow controller & allow carrier gas to flow through

             corresponding digital flow control.

5.1.8    Adjust the carrier gas flow rate with flow control (30 ml/min).

5.1.9    Gentle squeeze the bulb to force a soap film up into the gas stream. Start the stopwatch as

            soon as the film reaches to zero ml mark. Stop the watch when the film reaches to 30 ml

            marking. Note down the time require to reach the film from 0 to 30 ml mark. Calculate the

            flow rate using the following formula.

            Flow rate ml/min  = 60 X 30 (Dist. Between two points 30 ml)

                                                        Time taken in seconds

5.1.10      Similarly calibrate the flow rate after the time interval of 20 min, 40 min, & 60min and

             find out the difference between the readings.

5.1.11      Acceptance criteria: observed flow rate of the equipment should be within ±2ml/min of set flow rate

5.2        Detector precision and consistency of relative retention time:

5.2.1     Preparation of calibration solution (2000ppm):

            Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric flask 

            containing 5 ml methanol and dilute to mark with same solvent.

5.2.2    Inject 1.0µl of above calibration standard 5 times and observe area and RT.

5.2.3    ACCEPTANCE CRITERIA:

 The RSD of RRT Not More Than 2 %

 The RSD of area ratio Not More Than  5%

5.3       Detector Linearity:

5.3.1     Prepare the five different concentration solution as follow to check the detector linearity.

          1.Solution-1 (500 ppm):

            Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric flask

             containing 5 ml methanol and dilute to mark with same solvent. Take 2.5ml of this solution in 10ml volumetric flask and dilute to mark with same solvent.

          2. Solution-2 (750 ppm):

            Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric flask

            containing 5 ml methanol and dilute to mark with same solvent. Take 3.75ml of this

            solution in 10ml volumetric flask and dilute to mark with same solvent.

            3. Solution-3 (1000 ppm):

            Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric flask 

            containing 5 ml methanol and dilute to mark with same solvent. Take 5ml of this solution

             in 10ml volumetric flask and dilute to mark with same solvent.

         4. Solution-4 (1250 ppm):

             Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric             

             flask containing 5 ml methanol and dilute to mark with same solvent. Take 6.25ml of this

             solution in 10ml volumetric flask and dilute to mark with same solvent.

          5. Solution-5 (1500 ppm):

             Weigh accurately 100mg of Toluene and 100mg of 1-Butanol in 50 ml volumetric            

             flask containing 5 ml methanol and dilute to mark with same solvent. Take 7.5ml of this

             solution in 10ml volumetric flask and dilute to mark with same solvent.

5.3.2     Inject 3 replicate injections of the above solutions and observe area.

5.3.3     Plot the graph of linearity and calculate the correlation coefficient.

5.3.4     CHROMATOGRAPHIC CONDITION:

              Name of the instrument                          : GC [HP-6890]

              Column                                                    : BP-5 [30m X 0.32 mmID X 1.0µm] 

                                                                                            @ 2°C/min     

              Oven Temp.                                             : 50°C    (2min)       70°C (1 min)

              Injector Temp.                                         : 250°C

              Detector Temp.                                        : 250°C

              Carrier Gas                                               : N2 [1.0 ml], H2-30, AIR-300

              Injection Volume                                     : 1.0µl

              Split Ratio                                                : 10:1                     

              Acceptance criteria:  Correlation coefficient minimum 0.99

5.4        Calibration of Oven:

Calibration of   oven to be done by calibration department.

5.5        Frequency of calibration: Quarterly

6.0        Routine Maintenance:

6.1                Clean the all out side part of instrument.

6.2                Clean the injector and injector liner. Change the glass wool of injector liner. Change the septa  of injector port if required.

6.3                Check the all connection of gases for leakage.