Filtration Efficiency and Applicability of Filter Paper
In general, there are two types of filter paper in the laboratory: qualitative filter paper and quantitative filter paper. In the application of analytical chemistry, when sediment is separated after the inorganic compound is filtered, the residue which is collected on the filter paper can be used to figure up the wastage rate during the process of the experiment.
After filtration, many cotton fibers will be created on qualitative filter paper, so it is only suitable for qualitative analysis. As for quantitative filter paper, especially the ashless filter paper which is specially processed, it can effectively resist chemical reaction so that fewer impurities will be produced. Thus, it can be applied in quantitative analysis.
Apart from filter paper which is applied generally in the laboratory, it is also widely used in daily life or in engineering. It can be used for testing suspended particles in the air or applied in different industrial applications.
When choosing a proper filter paper, four elements have to be considered: hardness, filter efficiency, capacity, and applicability. Because the filter paper will be wet when doing filtration, high hardness must be considered in experimental procedures with a long time of filtration. Furthermore, filter paper with high efficiency means a high filtration rate and a high-resolution ratio.
Tips for selection filter paper
Several points should be considered in the selection of filter paper:
1. The use area of the filter paper is large, the dust content is large, the resistance is small, the service life is long, and the cost is correspondingly increased.
2. The smaller the fiber diameter is, the better the interception effect is and the higher filtration efficiency is.
3. The binder content of the binder in the filter material is high, the tensile strength of the paper is high, the filtration efficiency is high, the dust of the filter material is small, the resistance is good, but the resistance is correspondingly increased.
Hardness and Capacity of filter paper
The selection of appropriate filter paper can be determined by taking into account the following factors. For the hardness factors, filter paper often becomes wetting in the filtering process, so some experimental steps of long-term filtration should consider the use of tough filter paper after wetting.
For the capacity factor, the solid particles accumulated during filtration may block the pores on the filter paper, therefore, the denser the seepage pores are, the higher the capacity is and the more filters are allowed.
Filtration Efficiency and Applicability of filter paper
The density and the size of the water-permeable pores on the filter paper affect its filtration efficiency. The filter paper with high efficiency is high in filtering speed and high in resolution.
Applicability: Some filter paper is accomplished by adopted a special manufacturing step, for example, in the test of the nitrogen content in the blood, and the use of a nitrogen-free filter paper and the like.
Note that the filter paper cannot filter the zinc chloride, otherwise, the filter paper will be corroded and damaged by the zinc chloride.