Choosing the appropriate laboratory filter paper should consider the following four factors: hardness、filtration efficiency、capacity and applicability. 1. Hardness: the filter paper usually becomes wet when it is filtered, and some experimental steps of filtration should consider using tough filter paper after wetting. 2. Filtration efficiency: the size and degree of the seepage holes on the filter paper will greatly affect its filtration efficiency. High-efficiency filter paper is both fast filter speed and high resolution. 3. Capacity: the solid particles accumulated during filtration can block the holes in the filter paper, so the more dense the seepage holes are, the higher the capacity is and the more sample can be filtered. 4. Applicability: different filter paper has different properties, some filter paper is done with special production steps, and some filter paper can be used to determine the nitrogen content in the blood. Note that the filter paper cannot filter zinc chloride, otherwise the filter paper will be corroded by zinc chloride and the performance effect will be reduced. 5. Specification: the qualitative filter paper grade BIO-1 is of 0.3 wet bursts, 88 basis weight, 180 thickness, and 11μm particle retention.
Production Process of Filter Paper
Hawach filter paper disc can be used to remove harmful dust, smoke, poison from the gas, can separate impurity particles from the liquid, and can block bacteria, microorganisms, and so on. The filter paper is made from one or various kinds of inorganic fiber, plant fiber, and synthetic fiber, by adding the appropriate amount of chemical auxiliaries and fillers and using paper copying technology, it has good filtration performance and crisp porous filter medium.
In addition to the selection of raw materials, the proportion of filter paper also plays an important link in the production of filter paper.
Impact Factors in Performance
When filtering, in order to ensure that the filtration speed is fast, and to avoid the liquid flowing down the gap between the funnel and the filter paper, the filter paper should be close to the inner wall of the funnel and do not keep bubbles in the middle.
If the filter paper edge is higher than the funnel edge, the liquid oil in the filter may overflow; if the liquid level in the funnel is higher than the filter paper edge, the liquid will also flow down the gap between the funnel and the filter paper, the filter paper should be close to the inner wall of the funnel, and no bubbles should be left in the middle.
Different Properties of Filter paper
Filter paper is an effective filter medium, and filter paper has been widely used in various fields. According to the different types of fibers that make up the filter paper, the properties and uses of the filter paper are also different. There are ordinary filter paper for general occasions, glass fiber filter paper for high temperature, and super clean polypropylene filter paper, and so on.
Most of the filter paper is made of cotton fiber and is made in different ways for different applications. Because it is made of fiber, there are numerous small holes on its surface for liquid particles to pass through, while larger solid particles cannot. This property allows the separation of liquid and solid substances mixed together. While ordinary paper can only absorb 23% moisture, and cannot achieve the effect of filtration.