Single infiltration, heavy infiltration, countercurrent infiltration method,
willmedicinal materialsAfter being crushed, it is put into a special percolation cylinder or percolation tank, and the solvent is continuously introduced from the top of the percolation tank, so that it seeps through the medicinal material accumulation in the tank, and solid-liquid mass transfer occurs, so as to leach the active ingredients, and the leaching liquid is discharged from the lower outlet of the tank. This leaching method is called the "percolation method", and the resulting leaching liquid is called the "percolation liquid". Due to the continuous increase of the concentration of the leaching liquid during the percolation process, the density increases, and it gradually moves downward. The upper solvent or the thinner leaching liquid replaces its position, and the continuous training causes a large concentration difference, so that the diffusion can be carried out better. The main methods of percolation operation include single percolation method, heavy percolation method, countercurrent percolation method, and pressurized per
The characteristics of the percolation method are as follows:
1. Think of medicinal materials as equally large globular substances, layered into many layers from top to bottom, and regard the leaching solvent as an infinite number of parts, adding the impregnation process continuously. When the solvent passes through each layer of medicinal materials, a diffusion equilibrium process occurs in which the solvent is immersed in the medicinal materials, the dissolved solute and the solute diffuse outward, and then the solvent enters the next layer of medicinal materials, and then diffuses and rebalances, so that the diffusion equilibrium infiltration process is repeated.
2. The percolation extraction process is similar to multiple leaching processes, and the leaching liquid can reach a higher concentration, resulting in a good leaching effect.
3. It does not require heating and can be operated at room temperature.
4. Low solvent consumption, low filtration requirements, simplifying the slag separation process.
5. This method requires high operating techniques, otherwise it will affect the extraction efficiency.
Scope of application: suitable for extracting heat-sensitive, volatile or highly toxic traditional Chinese medicine materials; suitable for extracting traditional Chinese medicine materials with low active ingredient content or high leaching liquid concentration; for some other traditional Chinese medicine materialsextractFor viscous, non-flowable materials, such as frankincense, aloe vera, etc., this method should not be used.
