Carbon adsorbents—graphitized carbon black

In order to overcome the shortcomings of activated carbon, many studies were conducted both domestically and internationally in the early stages. They subjected the carbon black to high-temperature treatment in vacuum or a reducing atmosphere, such as heating it to 3000 ℃. As a result, graphite like crystal shapes were formed on the carbon surface. After this operation, the surface is uniform and the activation points are greatly reduced. The specific surface area decreased from a few hundred m2/g to below 30 m2/g. So it significantly improves the chromatographic peak shape and enhances the reproducibility of the analysis. According to the research of the former Soviet Union's Kishilev, believing that there are no functional groups and π bond on the surface of graphitized carbon black，so its adsorption mainly relies on dispersion force, which makes that the polarity of graphitized carbon black is smaller than that of squalane.

To adapt to the separation of various samples, various surface treatments can be applied, such as:

① Apply a small amount of fixed solution to eliminate residual activation points

② Phosphoric acid can be used to treat graphitized carbon black when separating acidic compounds

③ Organic alkali can be used to treat graphitized carbon black when separating alkaline compounds

④ Treating graphitized carbon black with hydrogen gas at 100 ℃ can remove surface oxygen, making it suitable for the separation of reducing substances