Learn About Qualitative Filter Papers

Manufactured from the same raw materials as the ashless grades, the qualitative filter paper is suited for ordinary filtration when we need to determine materials by using qualitative analytical techniques in the lab, with the features of fast flow rate due to their structure.

Qualitative filter paper has different designs. The standard qualitative filter papers with high purity are perfect for qualitative analyses where a low ash content are required. And the wet strengthened qualitative filter papers are basically used for analytical and routine analyses when no gravimetric analyses are required. We also can them for pressure or vacuum filtration.

Filter paper has excellent filtration property and strong absorption performance on liquid. Scientific workers use filter paper as a kind of media in analytical laboratories to separate solution from solid. Currently, there are mainly three kinds of filter papers which can be purchased in domestic market: quantitative filter papers, qualitative filter papers, and chromatography qualitative filter paper.

During the manufacturing processes of quantitative filter paper, the pulp is processed by hydrochloric acid and hydrofluoric acid. After washed by distilled water, most of the impurities inside the paper fiber can be filtered so that the filter paper is fit for precise quantitative analysis.

Types of Filter Paper

Domestic produced quantitative analysis filter paper falls into three types: fast speed, medium speed, and low speed. They are marked with a blue belt (fast speed), white belt (medium speed) and red belt (low speed) respectively. Commonly, there are two shapes of filter papers you find in the market: round and square. The former one is always with the diameter of 9 cm to 18 cm, while the latter one is with the dimension of 60 cm x 60cm and 30 cm x 30 cm.

Qualitative filter paper application areas

1. Qualitative analysis of liquid filtration
2. Separation of particulate matter, such as calcium oxalate, lead sulfate and calcium carbonate
3. Seed germination rate test and soil analysis
4. Wipe paper
5. Gas filtration and purification
6. Air sampling

General Notes of Using Filter Paper

1. Make use of natural filtration to separate the liquid from solid.
2. Considering of low mechanical strength and tenacity of filter paper, make sure of using less suction filtration.
3. It is better not to filter hot concentrated sulfuric acid or hot concentrated nitric acid through filter paper.

The qualitative filter paper is available for a wide range of applications. Hawach Scientific high-quality filter paper is in Low ash content (<0.1%). Nominal retention of our products can vary from 2.5um to 20um. Filtration speed is affected by these specifications and ranges from very slow to very fast. When choosing qualitative filter paper, you may consider about particle retention and nominal pore size required, wet strength level needed, and the diameter as well.

Hawach qualitative filter papers are suitable for a wide variety of round, square and folded filter papers for routine qualitative analysis. The filter paper raw materials are selected in multiple layers, and the production parameters are strictly controlled to ensure stable filtration test results.

Qualitative Laboratory Filtration Filter Paper Grade: BIO-2, Qualitative Chromatography Filter Paper Grade: BIO-5, Wet Strengthened Chemistry Filter Paper Grade: BIO-113.

Wet Strengthened Grade Filter Paper
Filter paper equivalent to Whatman
Medium Flow Filter Papers