Filter Paper Used as Filter Media
The paper of the filter paper is loose and has strong absorption of liquid. Analytical laboratories often use filter paper as a filter medium that separates the solution from the solid.
More importantly, during the manufacturing process of quantitative analysis filter paper, the pulp treated by hydrochloric acid and hydrofluoric acid, and washed by distilled water, will remove most of the impurities in the paper fiber, so after burning ,the residual ash is very small, almost no impact on the analysis results, it is suitable for precise quantitative analysis.
At present, the quantitative analysis filter paper produced in China can be divided into three categories: fast, medium and slow. The filter box is marked with white band (fast), blue band (medium) and red band (slow).
The shape of the filter paper has two kinds: round and square. According to the diameter, the size of the round fixed paper can be divided into d9cm, d11cm, d12.5cm, d15cm and d18cm. Square quantitative filter paper has 60cm * 60cm and 30cm * 30cm.

