Detailed Introduction of Qualitative and Quantitative Filter Paper

In the experiment, the filter paper is mostly used together with instruments such as a filter funnel and a Buchner funnel. Place the drained glass rod on the multilayer filter paper and apply even force to avoid the filter paper from being damaged.

About qualitative analysis filter paper

Filter paper is a kind of paper with good filtering quality, which is usually used in an assay laboratory to separate solutions and solids and do qualitative chemical analysis. Qualitative analysis filter paper is usually used in some non-numerical calculations and qualitative tests of chloride and sulfate. While quantitative analysis filter paper is used in filtering which needs precision numerical calculations. Qualitative analysis filter paper can not be used in qualitative analysis. It can only be used in filtering, precipitation, and general qualitative analysis

Grade 1: 11μm
Most commonly used in daily filtration, medium retention, and flow rate. It is very widely used in laboratory applications to clarify liquids. It is typically used for quantitative analytical separation of precipitates, such as lead sulfate, calcium oxalate, and calcium carbonate.

Grade 2: 8μm
Slightly stronger than Grade 1, but the filtration time is relatively long, and the adsorption is stronger than Grade 1.

Grade 3: 6μm
It is twice as thick as Grade 1, with good load ability and small particle retention. Due to its good wet strength, it is suitable for use in a Buchner funnel. Its high adsorption performance can be used as a carrier for samples.

Filter Papers

Grade 4: 20-25μm
It is very suitable for the rapid filtration of conventional biological liquids and organic extracts in the analysis. In air pollution monitoring, only high flow rates are required, but sampling of fine particles is not strict.

Grade 5: 2.5μm
The most efficient qualitative filter paper for collecting small particles with a slow flow rate. It is suitable for chemical analysis, clarified suspension, and water/soil analysis.

Grade 6: 3μm
The flow rate is twice that of Grade 5, but the particle retention is equal, which is often formulated for boiler water analysis.

About quantitative analysis filter paper

In the process of producing quantitative analysis filter paper, pulp processed by hydrochloric acid and hydrofluoric acid is washed with distilled water, which removes impurities from the paper fiber. There is little residual ash content after burning, and almost no influence in analysis results. Two kinds of filter paper in shape can be chosen, including circle and square with more specifications.

Grade BIO-40
The most widely used filter paper for routine applications with good retention and a high flow rate. This grade covers a wide range of laboratories and is frequently applied to clarify liquids. Traditionally, this grade is often used in qualitative analytical separations for soil analysis and seed testing procedures. The medium velocity, particle retention, and grey filter paper are fit for conventional filtration.

Grade BIO-41
Slightly more retentive than grade BIO-40 with a corresponding decrease in filtration time. More absorbent than BIO-40, the thickness is 215, the ash content is lower than 0.008, the wet burst is 0.3, and the particle retention is 20μm. It is the fastest gray-free filter paper and fits analysis processes such as aluminum hydroxide or iron hydroxide.

Grade BIO-42
It belongs to a slow-speed filter paper with the finest particle in quantitative filter paper. The wet burst is 0.7, the thickness is 200, and the basis weight is 100. The extra thickness gives improved wet strength and enables this grade highly suitable for use in the determination of elements in minerals such as calcium carbonate and strontium carbonate.

Hawach also provides other filter papers such as grade BIO-43 and grade BIO-44, contact us for more information on the product.