Matters Needing Attention On Filter Paper
The aperture of Qualitative Filter Paper
The pore size of the qualitative filter paper is irregular, usually, the pore size of the qualitative filter paper is large and quantitative is small. The filter paper filter speed is different, the aperture is also different. Generally speaking, the pore size of the qualitative filter paper is large and there is no very strict regulation. The quantitative filter paper is divided into three types: fast, medium and slow. The aperture of the filter paper is about 80 μ 120 μ m, 30 μ 50 μ m, and 1 μ 3 μ m, respectively.
The aperture of Quantitative Filter Paper
At present, the quantitative analysis filter paper produced in Hawach is divided into three categories: fast, medium and slow. White belt (fast), blue belt (medium speed) and red belt (slow speed) are used as the symbol classification on the filter carton. The shape of the filter paper is round and square. According to the diameter of circular fixed paper, it is divided into D7cm, D9cm, D11cm, D12.5cm, D15cm and D18cm. The square quantitative filter paper is 60cm × 60cm and 30cm × 30cm.
When using quantitative and qualitative analysis filter paper to filter precipitation, there are some suggestions:
1. Natural filtration is generally used to separate liquids and solid particles by using filter paper body and the ability to intercept solid particles;
2. Because the mechanical strength and toughness of the filter paper are as little as possible, if the filtration speed must be accelerated, in order to prevent filtration failure, layers of filter paper can be stacked in the funnel according to the pumping force, and when vacuum filtration is used, the filter paper can be stacked in the funnel according to the pumping force.
3. Do not filter hot concentrated sulfuric acid or nitric acid solution. The square qualitative filter paper is 60cm × 60cm and 30cm × 30cm.
Filter paper replacement time is depending on the number of impurities, you can regularly check the filter paper adsorption of impurities in the filtration process, look at the flow rate of the import and export samples, if more and more slowly indicates that more and more impurities adsorption needs to be replaced in time.
Operational Procedure for Filter Paper
The use of filter paper in the experiment is mostly used with filter funnel and Brinell funnel and other instruments. The filter paper can be folded into a needed shape before putting into operation. The common folding method is to fold the filter paper into a flower-like shape. The higher the folding degree of the filter paper, the higher the surface area it can provide, and the better the filtration effect is, but be careful not to overfold and cause the filter paper to break. Place the drained glass rod on the multi-layer filter paper and force evenly to avoid the damage of the filter paper.
Material Property for Filter Paper
At present, the filter paper used for industrial liquid filtration is mainly made of PPP material. However, if different materials are used or different processing conditions, even if the unit weight of the filter paper, the filtering accuracy expressed will also differ greatly. Most filter paper is made of fiber, there are countless holes in its surface for liquid particles to pass through, while larger solid particles cannot pass through. This property allows for the separation of liquid and solid substances mixed together.