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Showing posts from November, 2019

Fourier Transform Infrared Spectrometer (FTIR)

Fourier Transform Infrared Spectrometer (FTIR)  Principal:   Molecules are formed by chemical bonding of atom which FT/IR determine molecular structure vibration and rotational energy OR Identification of chemical function groups. Image Source-Google | Image by - QC/QA Methodology When IR beam goes to beam splitter. It is divided in two directions; one IR beam goes to movable mirror and other goes to stationary mirror. Movable mirror move around 21cm. Both IR beam return to beamsplitter thus it have different wavelength, these IR beam goes to detector through sample and detector send electronic signal to computer. Calibration of FTIR: Calibration done by the using calibrated polystyrene film which have 36 ┬Ám thickness and check the below parameter. Resolution performance Verification of wave number Resolution performance: Step 1= Record the spectrum of a secondary polystyrene film of 36 micro meter thickness the film has a reference number and a validity cer

Preparation of Normal Solutions

Preparation of Normal Solution   Preparation of 0.05N KOH Methanolic:   Take Potassium Hydroxide A.R grade. Weigh about 3.5 gm of potassium hydroxide in beaker and add 5 ml of water and d issolve it by stirring than add pure methanol to produce 1000 ml and mix well. Allow the solution to stand in tightly stopper bottle for 24 hours. After 24 hours, filter and standardize the solution t hen use for analysis. NOTE: Store in a tightly stopper bottle and protect from light. Standardization of 0.05 N KOH: Take about 5 gm of potassium hydrogen phthalate in a Petri dish and dried at 105 0 C for two hours. Weight about 0.35 gm substance and dissolve in 50 ml of distilled water and a dd five drops of phenolphthalein indicator. Titrate it against the potassium hydroxide solution until a permanent pink colour and note the burette reading. Repeat the above process in triplet set.                                  Wt of Substance x 1000   CALCULATION =----------

Troubleshooting of gas chromatography (G.C.)

Troubleshooting of gas chromatography (G.C.) Troubleshooting of split peak . We're going to write about split peaks. Let's say we're doing some gas chromatography, and we see some split peaks. What might be causing that? If we think about split peaks, in general what's happening there is something is interfering with our sample transfer from the injection port into the column, in most circumstances. That's not proceeding as a nice, tight band. It's getting spread out over time or separated from one another. What could cause that? It could be an injection problem. Even something as simple as, our syringe isn't smoothly injecting our sample into the injection port, or it could be that our sample is not making a homogeneous vapor cloud inside the inlet before it transfers into the column. If aerosol droplets might be making their way into the column, that could be a contributing factor to split peaks. If we want to manage that a little bit bet

Calibration of gas chromatography (G.C.)

Calibration of gas chromatography (G.C.) G.C.Calibration:   Calibration of oven:  This test verifies the G.C. oven temperature accuracy using two set points 50°C, 100°C  and 230°C.Fix the temperature probe on the column hanger so that the end of the probe is aligned with the instrument's oven sensor.Secure the probe by looping the cable around the column hanger or fastening it to the column hanger with high-temperature tape. Set point  of 50°C :  Set the oven temperature to 50°C .Turn on the oven and wait for 5 minutes after the oven is ready.Observe the temperature on the calibrated thermometer's display and when the temperature stabilizes, record the reading. Set point  of 100°C :  Set the oven temperature to 100°C .Turn on the oven and wait for 5 minutes after the oven is ready.Observe the temperature on the calibrated thermometer's display and when the temperature stabilizes, record the reading. Set point  of 230°C:  Set the oven temperature to 230°C .Turn o