2019年12月24日星期二

Availability And Specification Of Flash Column

In environmental analysis and testing, flash column is widely used in the pretreatment of samples, such as the organic pollution analysis of water and aerosols, the extraction solution is transferred to the chromatographic column, then the alkane part is eluted with cyclohexane, the polycyclic aromatic hydrocarbon pollutants are eluted with benzene, and the polar components are eluted with ethanol. In soil analysis, rare earth elements thorium, thallium and so on are separated by the alumina column.
Analysis Process
Adsorption column chromatography usually fills glass tubes with large activated porous or powdered solid adsorbents. When the mixture solution to be separated flows through the adsorption column, various components are adsorbed at the upper end of the column at the same time. When the eluent flows down, because of the different adsorption capacity of different compounds, the speed of downward eluting is also different, so different levels are formed, that is, the solute forms a number of ribbons from top to bottom in the column according to the affinity to the adsorbent. When eluted with solvent, the separated solute can be washed out and collected from the column.
Chemical Properties of Flash Column
Hawach flash Column specifications include two aspects: column length and column inner diameter. The selection of column specifications directly affects the analysis speed, separation ability, detection ability and solvent consumption for each analysis. For the same analysis time and separation degree: the column with a large inner diameter consumes more solvent than the column with a small inner diameter. Smaller inner diameter columns also require fewer samples for the same detection signal. Therefore, small inner diameter columns can be used when the sample size is limited. The long column can give a high degree of separation, and the short column can provide rapid separation. We can choose the appropriate chromatographic column according to the sample situation.

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