Similarity and Difference of Qualitative and Quantitative Filter Paper

Hawach is a professional lab science company. Its service industry covers many fields such as life science basic research, clinical disease diagnosis and control, development and application of biological products, pharmaceuticals, commodity inspection and quarantine, population and health, food safety, agriculture, forestry, animal husbandry, and fishery and so on.

Its main products range from the filter cartridge, bottle-top dispenser, filter paper, pipette, to flash column, HPLC column and stainless steel molecular distillation, and so on.

Qualitative analysis filter paper generally has more residual ash, which is only used for general qualitative analysis and for filtering sediment or suspended matter in solution and cannot be used for quality analysis. When filtering the sediment, we should pay attention to:

1. Natural filtration is generally used, and the filter paper body and the ability to trap solid particles are used to separate liquids and solids;
2. Due to the ordinary mechanical strength and toughness of the filter paper, it is suitable to use less suction to filter. If it is necessary to speed up the filtration speed, stack 2 ~ 3 layers of filter paper in the funnel according to the suction force when filtering by the air pump. When using vacuum suction filtration, first put a layer of dense filter cloth on the funnel, and then put filter paper on it to filter;
3. Filter paper should not filter hot concentrated sulfuric acid or nitric acid solution.

Three Types of Filter Paper

Currently, there are mainly three kinds of filter paper: quantitative analysis filter paper, qualitative analysis filter paper and chromatography qualitative analysis filter paper.

1. Quantitative Analysis Filter Paper

In the manufacturing process, reacting with hydrochloric acid, hydrofluoric acid treatment and distilled water washing, most of the impurities of paper fiber will be removed. So after burning, few residual ashes exists, which has little impact on analysis results.

2. Qualitative Analysis Filter Paper

This one actually has comparatively more residual ash, which only serves for general qualitative analysis and filtering the precipitation or suspension in solutions, but for quality analysis.

3. Chromatography Qualitative Analysis Filter Paper

Its major role is the support of paper chromatography.

filter paper filtration

The similarity between Qualitative and Quantitative Filter Paper

The type and specification of qualitative filter paper are basically the same as that of quantitative filter paper, which provides fast, medium speed and slow speed.

In the production process of filter paper, the raw materials are treated with various acids such as hydrochloric acid, and the impurities in the paper fiber were removed by distilled water so that the residual ash after burning remains little, which has little effect on the analysis results and brings beneficial for precise quantitative analysis.

Difference between Qualitative and Quantitative Filter Paper

The difference between quantitative filter paper and qualitative filter paper is in the ash amount produced after ashing. The qualitative filter paper may not exceed 0.13%, and the quantitative filter paper may not exceed 0.0009%. Ash free filter paper is a quantitative filter paper, which provides with ashless than 0.1 mg, this weight is negligible on the analytical balance. Note that both quantitative filter paper and qualitative filter paper are cellulose filter paper, which cannot be used to other types of filter paper such as glass microfiber filter paper.

HAWACH specially designs three kinds of filter papers with different flow rates to meet the needs of users with different uses: fast, medium speed, and slow speed. Different types of filter paper have different physical and chemical indexes. HAWACH quantitative filter paper has different sizes and specifications, taking into account the filtration speed and particle interception effect. It is used for particle collection in food analysis, soil analysis, and air pollution monitoring. It is also used for inorganic analysis in the construction industry, minerals, and steel industry.

Comparison of Quantitative filter paper and Qualitative filter paper

Qualitative filter paper is applied to solution filtering, while quantitative filter paper is designed for filtration based on precise calculation numerical value. And treatment in high-temperature furnace is required after the filtering of quantitative filter paper. Besides, concepts of quantitative filter paper and qualitative filter paper appear because of the cellulose filter paper, so they can not be adapted to other filter paper types like glass microfiber filter paper.
Hawach provides Qualitative Filter Paper Disc Grade: BIO-1, Qualitative Laboratory Filtration Filter Paper Grade: BIO-2, Quantitative Roll Filter Paper Grade: BIO-43, Wet Strengthened 10 Micron Filter Paper Grade: BIO-91, and other filter papers for your choice.