Analysis of the carbon number distribution of F-T synthesized waxes

Generally speaking, gas chromatography is used for analysis; the analysis results of gaseous products and liquid products (oils and waxes) are calculated separately, and then, by taking into account their masses, the product distribution is determined. There are many detailed questions; you can ask them again, and I’ll help you answer each one. Gas chromatography equipped with a standard capillary column designed for separating hydrocarbon compounds – such as the Agilent 6890/7890 models, with an injection port temperature of up to 350 degrees, a FID detector temperature of 350 degrees, and a 60m HP-5 capillary column – can analyze compounds up to C60; beyond that it’s not possible. This is due to the temperature limitations of the injection port, the detector, and the chromatography column. If high-temperature resistant injection liner materials and high-temperature resistant chromatography columns are used (in our laboratory we use columns with a maximum temperature of 450 degrees, namely SGE’s HT-5), it should be possible to analyze compounds up to C200, though I haven’t tried this yet. In our laboratory, the concentration of compounds above C80 is very low. In short, if one wants to analyze components with high carbon numbers, high requirements are placed on the chromatography system; the injection port, chromatography column, and detector all need to be equipped with materials that can withstand high temperatures. Furthermore, on a laboratory scale, iron or cobalt catalysts are generally used, and the C200 content in the products is very low; in fact, the amount of C80 and above is also minimal. In any case, even when using highly active cobalt catalysts in the laboratory, after several months of operation, no C200 has ever been detected in the products. However, if a ruthenium catalyst is used, the carbon number in the product can reach a higher value. In industrial production, even in the waxes produced using cobalt and iron catalysts, the content of compounds with a molecular weight of C200 or higher is not high. In fact, if you are to conduct product analysis, C50 is usually sufficient to provide useful information; there is no need to analyze up to such a high carbon level as C200. The alpha value at C50 is roughly the same as that at C200.

Sorry, the second floor account is my alias; haha, I made a mistake when logging in today. I won’t use an alias to log in anymore

It is already very difficult to analyze compounds with a carbon count of 100. Actually, there’s no need to reach 200 carbon atoms either