Inert Support of Filter Paper
Hawach Scientific filter paper is a common filter tool in the chemical laboratory, the common shape is round, and the common material is cotton fiber. Paper chromatography uses filter paper as an inert support. Fiber and water of filter paper provide strong affinity, which can absorb about 22% of water, and 6~7% of the water is in the form of a hydrogen bond with the hydroxyl group of cellulose.
The affinity of filter paper fiber and the organic solvent is very weak, so the general paper chromatography is actually using the binding water of filter paper as the stationary phase and organic solvent.
Distribution and Purification of Filter Paper
when the mobile phase passes through the sample along with the paper, the solute on the sample point is continuously distributed between the organic phase and the water, and a part of the sample moves with the mobile phase and enters the solute-free zone, and then redistributes again.
Meanwhile, part of the solute enters the stationary phase from the mobile phase. With the continuous movement of the mobile phase, various parts are continuously distributed according to respective distribution coefficients, and move along the mobile phase, so that the material can be separated and purified.
Matters Needing Attention in Filter Paper
There are some matters should be kept in mind: first, the chromatography filter paper should close to the inner wall of the funnel; second, the edge of filter paper should lower than the funnel edge, filtrate should lower than the edge of filter paper; third, the beaker should close to glass rod, glass rod should close to three-layer filter paper, leakage bucket diameter should close to the inner wall of the beaker.
Moreover, filter paper after wetting should stick to the inner wall of the funnel, if there is a gap between the filter paper and the inner wall of the funnel, the speed of filtration will be relatively slow. Because when the chromatography filter paper is close to the inner wall of the funnel, the filtered liquid constantly flows out from the lower end, thus making the pressure below the filter paper less than the atmospheric pressure above, thus making the filtration faster and smoother.
Furthermore, the funnel tip should close to the inner wall of the beaker, if the tip of the funnel not close to the inner wall of the beaker, the speed of filtration will be affected to some extent. And there are other reasons for the turbidity of the filtrate, in which the chromatography filter paper is damaged or the liquid level is higher than the edge of the chromatography filter paper.
In the manufacturing process of Hawach quantitative chromatography filter paper, treated by hydrochloric acid and hydrofluoric acid and washed by distilled water, most of the impurities in the pulp are removed. The ash is very little after burning, which complies with international rules in this area. Made of high-quality cellulose, Hawach quantitative chromatography filter paper is high grade ashless, and suitable for almost all precipitates.
Made under the intense quality control standards, all the Hawach quantitative chromatography filter paper will make it ideal for use to meet your needs.
Inert Support And Matters Needing Attention of Chromatography Filter Paper
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