What factors affect the extraction effect of the microwave extractor

Microwave extractor is a liquid extractant to treat a two-component or multi-component solution that is not mutually soluble with it, and the mass transfer separation process to realize component separation is a widely used unit operation
.

The difference in solubility or partition coefficient of the compound in two mutually incompatible (or slightly soluble) solvents allows the compound to be transferred from one solvent to another
.

What factors affect the extraction effect of the microwave extractor: Extraction temperature: In a microwave closed vessel, the boiling point of the solvent is higher
than at normal pressure due to the internal pressure reaching more than a dozen atmospheres.

Therefore, microwave extraction can achieve an extraction temperature that cannot be achieved with the same solvent at normal pressure, thereby improving the extraction efficiency, but not decomposing the extract to be measured
.

The trend of the extraction rate increasing with the increase of temperature is only manifested in the less high temperature range, and the optimal extraction temperature of each substance is also different
.

Extraction time: Microwave extraction time is related
to the amount of sample to be measured, solvent volume, and heating power.

In general, the extraction time is within 10 to 15 min
.

In the extraction process, the general heating of 1 ~ 2 minutes can achieve the required extraction temperature
.

The results of studies have shown that the extraction rate increases with the extension of the extraction time, but the increase is not large and negligible
.

Extraction solvent: Extraction solvent, extraction power and extraction time are the main process parameters
affecting the efficiency of microwave extraction.

The choice of extraction solvent is critical
to the effect of extraction results.

In microwave extraction, the solvent must first be required to have certain properties to absorb the microwave energy for internal heating; Secondly, the selected solvent must have a strong solubility for the target extractant; In addition, the boiling point of the solvent and its interference with
subsequent assays need to be considered.