How to Choose the Hawach Right Filter Papers?

Choosing the right filter for your filtration will be a big help to make sure that you can get the desired results for your applications.You can select a suitable filter material and size, after you consider whether you need vacuum or gravity filtration. Since there are so many types and sizes of filter papers available, you should know how to choose the right one.

When you choose the filter material, you need to consider chemical compatibility, pore size and your filtration method upon the different filter types suitable for different methods.In addition to the material and method, you should consider the amount of your filtration and select the filter of right size.

Hawach provides qualitative and quantitative filter papers. The qualitative filter paper is perfect to identify the properties of substances in qualitative analysis. And the quantitative filter paper is for filtration after the filtration. Hawach’s full lines of different filter paper products can always meet your needs of different levels of purity, hardness, flow rate, loading capacity, and chemical resistance.

Knowledge of Technical Index
The technical index of the filter paper can be divided into two aspects, one is the filter characteristic of the filter paper and the other is the physical property. The filter characteristics include air permeability, gas resistance, maximum pore size, and average pore size. Physical properties include quantitative, thickness, stiffness, corrugation depth, durability, resin content, etc.

The Function of Filter Paper

Most of the filter paper are made of cotton fiber and processed with different methods according to different purposes. As one kind of fiber products, there is countless micropore on the surface of filter paper to let liquid particle go through. On the other hand, the solid particle with larger sizes cannot go through the filter paper. By this feature, filter paper can be used to separate solid matters from liquid matters.

Qualitative Filter Papers
Quantitative Filter Papers

To be specific, the function of filter paper is to filter paper chromatography. As inert support, the filter paper fiber has a strong affinity with water and it can absorb 22% of the water. On the contrary, the filter paper fiber has weak affinity with organic solvent.

In general, filter paper chromatography uses bound water in the fiber as the immobile phase and the organic solvent as mobile phase. When the mobile phase flows through the sample on filter paper, the solute on the sample is distributed continually between water and organic solvent. Part of the sample moves with the mobile phase and flow into the non-solute area and some other solute will flow into the immobile phase with the mobile phase. With the continuous move of the mobile phase, separation and purification of matters can be achieved through filter paper.

Classification Factor
The filter paper can be divided into two types, one is qualitative, and one is quantitative. Qualitative filter paper generally refers to the formation of cotton fibers on its surface after filtration, which is generally only suitable for qualitative analysis. While the quantitative filter paper is generally used for filter paper with ash-free stage, a special treatment program must be adopted in the process of using, so that it can effectively resist certain chemical reactions, and reduce the impurities generated on the surface of the filter paper.