Filter paper is one of the essential laboratory tools that play an important role in the laboratory. With diverse usage requirements, manufacturers have created various types of filter paper. This not only allows users to choose freely but also creates many challenges. So, what is filter paper? How many types are there? What technical specifications should we pay attention to? In this article, Cường Thịnh will guide you through all the above questions.
What is filter paper?
Common types of laboratory filter paper today
Filter paper, known as filter paper in English, is a consumable material used for filtering and determining certain properties of filtered substances in the laboratory. Additionally, it is considered a pure filter to separate impurities from liquids or air. In fact, it is an excellent choice for use in water, air, and industrial environments.
Common types of filter paper today
Quantitative filter paper is a popular laboratory tool.
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Quantitative filter paper This type of filter paper is used for testing and analyzing experiments corresponding to quantitative chemical analysis methods. Its primary role is for weighing and analyzing experiments that require filtration after ashing. Additionally, the weight of the ash after ashing serves as a fixed value for the function of conventional filter paper.
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Qualitative filter paper This type of filter paper is used for qualitative chemical analysis and corresponding filtration. The filtration speed of this laboratory filter paper is influenced by technical specifications and ranges from very slow to very fast. In qualitative filter papers, the ash content after ashing does not exceed 0.13%.
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Ashless filter paper Ashless quantitative filter paper has an ash content of less than 0.1mg. With this weight, the residual ash can be ignored in the analysis. This laboratory filter paper is made from cellulose fibers and is used for general filtration. The particle retention rate can be reduced to 2.5 µm. This type of filter paper is used for basic gravity filtration using glass or plastic funnels.
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Glass microfiber filter paper Glass microfiber filter paper is made from 100% borosilicate glass microfiber, which allows retention of particles down to very small ranges. It can also withstand high temperatures of up to 550°C. Therefore, this laboratory filter paper can be used in gravity analysis, especially in situations with ignition risks.
Top 5 Most Common Filter Papers Today
- Quartz fiber filter paper This is a type of chemical filter paper without binders and is sterilized. It has high purity with very low metal content, does not absorb NOx and SOx dioxide. Additionally, it can withstand temperatures up to 1000ºC and has high chemical durability. Therefore, it is used for air samples in acidic gases, smoke ducts, and vapor systems.
Technical specifications of laboratory filter paper to consider
The pore size of filter paper determines the filtration speed.
First, the most important specification to consider is the pore size. This refers to the nominal size of the pores in the filter. Particles larger than this size will be trapped, while particles smaller than this size can pass through the filter. This also affects the filtration speed of each type of laboratory filter paper, whether fast or slow.
The second specification to consider is the ash content after ashing. Ashless means no ash, while Low Ash refers to low ash content. Quantitative cellulose filter papers can be described as ashless or low ash. This is determined by burning the cellulose filter paper at 900°C in the air. Ashless filter paper is used in critical applications, such as in gravity analysis of quantitative filter papers.
Conclusion
Currently, there are many ways to choose laboratory filter paper. However, all choices should be based on the intended use, reflected through the types of filter paper and technical factors. With the information provided above, we hope customers will have a comprehensive understanding of this useful product. From there, they can determine their needs and make the most appropriate choice.
There are various products from different manufacturers, but we recommend using reputable manufacturers from countries like Japan, the U.S., and Taiwan. These products offer high quality, durability, and their price is not much higher than Chinese-made products. For more information about filter paper, please feel free to contact us for detailed consultation and support!
