Is there anyone who knows about gas chromatography? Urgently needed
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Gas chromatography is used to determine the content of the CH3CHClF product; the boiling point of this substance is around 0–4 degrees Celsius. How should the following parameters be determined: Indicator: concentration? Test conditions: column temperature? Vaporization temperature? Detector temperature? Injection volume? Can the rest be like this? Nitrogen, 40 ml/min. Hydrogen: 30 ml/min, Air: 300 ml/min.
I am good at GC analysis and might be able to help you solve the problem, but the poster’s post is too simple; I don’t know where to start! Is the sample to be analyzed in gas phase or liquid phase? What is the approximate composition of the sample? (Which substances? What are the main concentration ranges for various substances? ) How’s the GC you’re using? (With a capillary chromatography column? FID detector? Is there shunting? ) Only by knowing these situations can I help you analyze the conditions.
The determination is carried out by gas chromatography, using a hydrogen flame detector; the percentage composition of each component is calculated by peak-area normalization. Equipment: HP5890 chromatograph (with HP-1 column), digital processor, standard micropipettes. The sample is in liquid form; the main product is CH3CHClF, along with CH2CHCl and hydrogen fluoride
Weakly polar capillary chromatography columns can be used, such as EC-1, SE-54, etc； Methyl acetate can be used as an internal standard for the quantification of CH3CHClF concentration ； Column temperature: 50 degrees ； Vaporization temperature: 100 degrees ； Detector temperature: 100 degrees ； Injection volume: around 1 um. The carrier gas is nitrogen; 40 ml/min might work, and it can be adjusted according to the split ratio. Hydrogen: 30 ml/min, air: 300 ml/min – that should be sufficient! The above is merely a suggestion; the specific GC conditions need to be determined through multiple experiments
Can that one measure temperature in the same way as the vaporization temperature? Isn’t a temperature difference required? The vaporization temperature and the temperature in the detection chamber should be 30-70 degrees higher than the column temperature, right? This post was last edited by *aosongsong on 2007-12-13 at 15:25.]