The unadsorbed material then passes through the second activated carbon, the less adsorbed material is adsorbed on the second column, and the unadsorbed material finally passes through the first activated carbon.
Thus, through three columns in turn, on which the adsorbed substances are eluted with appropriate eluents, it is possible to obtain a better separation of the very complex natural medicinal constituents.
Because of the fine particles of powdered activated carbon, it is inconvenient to operate, so in the practical application process, generally try not to use the first kind of active carbon.
No powdered activated carbon is another important reason for the adsorption of powdered activated carbon is too strong, there are many substances adsorbed on it is very difficult to elute, usually will be used after the adsorbent deactivation.
The same fineness of activated carbon, the strength of its adsorption and the structure of the adsorbed material.
In general, all compounds with conjugate double bond structure, activated carbon is easy to adsorption, the more often double bond, activated carbon on its adsorption capacity is greater.
This is mainly because activated carbon has a hexagonal structure formed by the combination of covalent bonds (with large bond structure properties of aromatic ring), which is easy to be mutual with common double bonds.
Role.
Some pigments, most of which have a strategic structure, are easy to be adsorbed on the carbon. In the process of recrystallization, activated carbon decolorization is added to remove impurities. This is the reason.
For the same skeleton compounds or the same type of compounds, the introduction of amine, hydroxyl, carboxyl and other polar groups will often increase the adsorption of activated carbon to it.
The adsorption power of activated carbon on the material is related to the structure of the adsorbed material and the solvent used.
https://www.dxdcarbon.com/product/china-supplier-coconut-shell-activated-carbon-price -per-tonThe adsorption capacity is usually strongest in water, followed by ethanol and acetone, and weaker in other solvents.
Therefore, the decolorization with activated carbon is the best in aqueous solution, followed by ethanol and acetone, and almost no decolorization ability in other organic solvents.
The size of the adsorption force of activated carbon on the solute in the solution, in addition to the size of the activated carbon and the structure of the adsorbed matter, must also consider the interaction between solute and solvent, that is, must also consider the size of the solute solubility of the solvent.
https://www.coconutactivatedcarbon.com/Activated carbon chromatography is often carried out in an aqueous solution, the solubility of the adsorbate in water when there is a key role in the adsorption capacity or adsorption stability.
For example, the adsorption of activated carbon on iodine, flash iodine in the water towel solubility is minimum, so the adsorption of activated carbon in water is the largest.
Another example of activated carbon on the adsorption of trans butadienoic acid is greater than cis butadienoic acid, the reason is that the solubility of trans butadienoic acid in water than cis butadienoic acid.Activated carbon has no adverse adsorption effect on some substances, causing some substances to adsorb on it can not elute.
Therefore, in the separation of activated carbon adsorption of the material, must first activated carbon deactivation.
The commonly used reagent for activated carbon deactivation is a long chain aliphatic compound, such as stearic acid, oleic acid, undecanoic acid, octadecane, octadecanamine, etc., among which the most common is stearic acid.
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