About Features, Application, Choice, and Use of Qualitative Filter Paper

General introduction
Qualitative filter paper is mainly used for chemical qualitative analysis and filtration separation of related solutions and can be used to detect its purity. Compared with other forms of similar filter paper, the pleated filter paper can speed up the flow and increase the weight.

There are three types of qualitative filter paper based on the separation performance and filtration speed: fast, medium, and slow. From the appearance point of view, it can be divided into two types: round and square. Qualitative filter paper square ones are 60 × 60 cm, 30 × 30 cm, etc. The diameter of the qualitative filter paper circle is Φ7cm, Φ9cm, Φ11cm, Φ12.5cm, Φ15cm, Φ18cm, Φ22cm, etc.

Features of filter paper

The purity, high quality, and uniformity of qualitative filter paper lay the foundation for users to obtain successful experimental results and reproducibility. The HAWACH qualitative filter paper is made of carefully selected cotton fibers and its strict quality control ensures the consistency of the product level, which is very important for chromatography experiments.

Its composition is high-quality pure cotton cellulose without any additives, with stable filtration performance and good uniformity, which is very important for chemical analysis; the adsorption capacity of this type of chromatography paper is generally higher, with better resolution, smooth surface, high wet strength, and wide application range.

1. Made of 100% alpha cotton cellulose, ash content 0.1%
2. Stable pH value of 0 12; resistant to high temperature to 120 ℃
3. No acid, alkali, organic solvent containing impurities, etc.
4. Qualitative analysis to determine and identify materials.

Application of filter paper

1. Widely used in general laboratory filtration
2. Suitable for liquid clarification, analysis, and separation
3. For air and water quality analysis
4. For rough sample preparation
5. Filter papers used in paper chromatography
6. Gravity filtration: used to separate solid particles from liquids through the force of gravity. Common in chemistry labs for purifying solutions.
7. Qualitative analysis: employed in analytical chemistry for qualitative tests to determine the presence or absence of specific substances in a sample.
8. Sample preparation: used to prepare samples for further analysis by removing impurities or unwanted solids from a solution.
9. Clarification in food and beverage industry: employed to clarify liquids like juices, syrups, and wines by removing suspended particles.

How to choose the qualitative filter paper?

For many companies or factories, these factors need to be considered when buying filter paper, so that they can understand their specific prices. The filter paper is made of pure cotton linters, which has good filtration and absorption performance, high compressive strength, uniform paper quality, and high filtration accuracy. The pH is neutral, and the water absorption is strong. Its function cannot be replaced by filter cloth and filter mesh.

Therefore, when buy lab filter paper, you must consider the effective area. The larger the use area, the greater the dust holding capacity, the lower the resistance, and the longer the service life. Of course, the cost will increase accordingly. It will have a better interception effect if the fiber diameter is small. The filtration efficiency is correspondingly higher.

How to use the qualitative filter paper?

Qualitative filter paper generally adopts natural filtration, which uses the ability of filter paper to trap solid particles to separate liquid and solid. Due to the mechanical strength and toughness of the filter paper, the method of suction filtration should be used as little as possible. If the filtration speed must be accelerated, in order to prevent the filtration failure caused by the filtration. The filter paper can be folded into two or three layers for air pump filtration. When vacuum filtration is used, a layer of dense filter cloth should be placed first, and then filter paper should be placed on it for filtration. Hot concentrated sulfuric or nitric acid is better not filtered.

This type of filter paper is the most commonly used in conventional filtration. Different filter papers have different separation capabilities and different flow rates. Generally, when the filtration rate is slow, the separation ability is stronger, the adsorption effect is obvious, and the particles can be retained to a greater extent. It is suitable for chemical analysis and clarifies suspended solids, which takes a long time. For industrial filtration, you can choose medium-speed filter paper, which not only ensures filtration performance but also saves time. With medium flow rate and medium particle retention, it can filter high-viscosity liquids and emulsions (such as sweet juice, wine, syrup, resin solution, oil or plant extracts, Chinese medicine soaking liquid). The quick filter paper is slightly thicker than that, has a higher load capacity, and is suitable for coarse particles, medium and colloidal sediments.

Qualitative filter paper covers most of the scope of laboratory applications. It is often used for clarification of liquids and also used for qualitative analysis and separation of sediments. In industrial filtration, it is often used to separate solid substances or extract liquids from related liquids. It is not used as an analytical filter paper, but as a paper filter material. It is used for coarse filtration from western medicine liquids, coarse filtration and fine filtration of Chinese patent medicines, to chemical product filtration, electroplating industry filtration, etc., and the grades of filtration products vary greatly. This kind of filter paper is also often used in daily analysis applications in different industries.