1.0 PURPOSE:
1.1 To lay down the procedure for Calibration of Gas chromatograph.
2.0 SCOPE:
2.1 This procedure is applicable for Calibration of Gas chromatograph in Quality control department.
3.0 RESPONSIBILITY:
3.1 Jr.Executive / Sr.Executive -QC.
4.0 ACCOUNTABILITY:
4.1 Asst. Manager- QC.
5.0 PROCEDURE:
5.1 Operate the instrument as per the respective SOP and perform the following tests.
5.1.1 FLOW RATE CHECK
5.1.2 OVEN TEMPERATURE CHECK
5.1.3 PRECISION
5.1.4 LINEARITY TEST
5.2 Flow rate check:
5.2.1 Connect Flow tracker to the detector outlet port.
5.2.2 Set the Carrier gas flow as below and measure the observed flow by Flow tracker.
5.2.2.1 0.5 mL/min.
5.2.2.2 1.0 mL/min.
5.2.2.3 5.0 mL/min.
5.2.2.4 10.0 mL/min.
5.2.3 Record the results as per Format No.xxxxx
5.2.4 Acceptance criteria: Refer Format No.xxxxx
5.3 Oven temperature check:
5.3.1 Place the temperature measurement probe inside the oven.
5.3.2 Set the oven temperature to 40°C. Wait for oven readiness.
5.3.3 Note the observed temperature as read by the probe in triplicate over a period of 10 min.
5.3.4 Repeat the procedure for 100, 150 and 190°C.
5.3.5 Record the results as per Format No.xxxxx
5.3.6 Acceptance criteria: ±2.0°C
5.4 Precision (For manual injection/auto injector):
5.4.1 Chromatographic conditions:
5.4.1.1 Column: 30 m x 0.32 mm, 1.8?, coated with 6% cyanopropyl, 94%dimethyl polysiloxane. (DB 624 or equivalent.)
5.4.1.2 Detector : FID
5.4.1.3 Carrier pressure (He) : 25 kpa. (1kpa = 0.145 psi)
5.4.1.4 Oven temperature programme:50°C(3 min) 25°C/min 250°C(4min)
5.4.1.5 split ratio : 1:10
5.4.1.6 Injector Temperature: 180°C.
5.4.1.7 Detector Temperature: 250°C.
5.4.1.8 Injection Volume: 0.2 ?l.
5.4.1.9 Hydrogen : 40 mL/min.
5.4.1.10 Air : 400 mL/min
5.4.2 Preparation of solution:
5.4.2.1 Transfer 20 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask, make up to volume with ethyl acetate.
5.4.3 Perform six replicate injections of above solution and record the chromatograms.
5.4.4 Record the data in Format No.xxxxx.
5.4.5 Calculate the % RSD for retention time and area of individual component solvents.
5.4.6 Acceptance criteria: %RSD of retention time is not more than 1.0% and % RSD of area is not more than 10.0%.
5.5 Precision (For Head space sampler):
5.5.1 Chromatographic conditions:
5.5.1.1 Column: 30 m x 0.32 mm, 1.8 ?, coated with 6% cyanopropyl, 94%dimethyl polysiloxane. (DB 624 or equivalent.)
5.5.1.2 Detector : FID
5.5.1.3 Carrier pressure (He) : 25 kpa. (1kpa = 0.145 psi)
5.5.1.4 Oven temperature programme:40°C(15 min) 15°C/min 200°C(5min)
5.5.1.5 Split ratio: 1:10
5.5.1.6 Injector Temperature: 220°C.
5.5.1.7 Detector Temperature: 260°C.
5.5.1.8 Hydrogen: 40 mL/min.
5.5.1.9 Air : 400 mL/min
5.5.2 Head space parameters:
5.5.2.1 Vial Temperature : 80°C.
5.5.2.2 Loop Temperature : 100°C.
5.5.2.3 Tr. Line Temp. : 110°C.
5.5.2.4 GC Cycle Time : 38min.
5.5.2.5 Vial Eq. Time : 20 min.
5.5.2.6 Pressurisation Time : 0.2 min.
5.5.2.7 Loop Fill Time : 0.05 min.
5.5.2.8 Injection Time :0.2 min.
5.5.2.9 Vial Pressure : 10.8 Psi.
5.5.3 Preparation of solution:
5.5.3.1 Stock solution: Take 0.6 g of methylene chloride, 0.06 g of chloroform, 0.08 g of Trichloroethylene and 0.38 g of 1,4-dioxane into a 50 ml volumetric flask containing about 20 mL of dimethylformamide and make up to volume with dimethylformamide.
5.5.3.2 Standard solution: Dilute 1 ml of the stock solution to 50 ml with dimethylformamide.
5.5.3.3 Take 0.5 ml of standard solution into a 10 ml vial containing about 0.2 g of sodium chloride and add 0.5 ml of water. Seal the vial with a septum and crimp cap immediately. Prepare six vials following the above procedure.
5.5.3.4 Blank solution: Take 0.5 ml of Dimethylformamide in 10 ml vial containing about 0.2 g of sodium chloride and add 0.5 ml of water. Seal the vial with a septum and crimp cap.
5.5.4 Chromatograph the above-prepared six vials and blank with the chromatographic conditions given above.
5.5.5 Record the data in Format No.xxxxx
5.5.6 Calculate the % RSD for retention time and area of individual component solvents.
5.5.7 Acceptance criteria: %RSD of retention time is not more than 1.0% and % RSD of area is not more than 15.0%.
5.6 Linearity test (For manual injector /auto injector):
5.6.1 Chromatographic conditions:
5.6.1.1 As per 5.5.1
5.6.2 Preparation of solutions:
5.6.2.1 Solution A: Transfer 10 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask. Make up to the mark with ethyl acetate.
5.6.2.2 Solution B: Transfer 15 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask. Make up to the mark with ethyl acetate.
5.6.2.3 Solution C: Transfer 20 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask. Make up to the mark with ethyl acetate.
5.6.2.4 Solution D: Transfer 25 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask. Make up to the mark with ethyl acetate.
5.6.2.5 Solution E: Transfer 30 ml each of methanol, ethanol and acetone into a clean and dry 100 ml volumetric flask. Make up to the mark with ethyl acetate.
5.6.3 Chromatograph the above-prepared solutions (five) separately and record the chromatograms.
5.6.4 Record the data in Format No.xxxxx.
5.6.5 Calculate the correlation co-efficient of concentration and area for individual component solvents.
5.6.6 Acceptance criteria: Not less than 0.99.
5.7 Linearity test (For Head space sampler):
5.7.1 Chromatographic conditions: As per 5.6.1
5.7.2 Preparation of solutions:
5.7.2.1 Solution A: Take 0.8 ml of stock solution (5.6.3.1) and dilute to 50 ml with dimethylformamide in a 50 ml volumetric flask.
5.7.2.2 Solution B: Take 0.9 ml of stock solution and dilute to 50 ml with dimethylformamide in a 50 ml volumetric flask.
5.7.2.3 Solution C: Take 1.0 ml of stock solution and dilute to 50 ml with dimethylformamide in a 50 ml volumetric flask.
5.7.2.4 Solution D: Take 1.5 ml of stock solution and dilute to 50 ml with dimethylformamide in a 50 ml volumetric flask.
5.7.2.5 Solution E: Take 2.0 ml of stock solution and dilute to 50 ml with dimethylformamide in a 50 ml volumetric flask.
5.7.2.6 Take 0.5 ml of solution A into a 10 ml vial containing 0.2 g of sodium chloride, add 0.5 ml of water. Seal the vial with septum and crimp cap immediately.
5.7.2.7 Similarly prepare vials taking solutions solution B, solution C, solution D and solution E separately.
5.7.2.8 Blank solution: Take 0.5 ml of Dimethylformamide in 10 ml vial containing about 0.2 g of sodium chloride and add 0.5 ml of water. Seal the vial with a septum and crimp cap.
5.7.3 Chromatograph the above prepared vials (six) and record the chromatograms.
5.7.4 Record the data in Format No.xxxxx.
5.7.5 Calculate the correlation co-efficient of concentration and area for individual component solvents.
5.7.6 Acceptance criteria: Not less than 0.99.
5.8 Frequency: Once in six months.
Gas chromatograph, cyanopropyl, polysiloxane, trichloroethylene, sodium chloride
