Steps For Operation Of Filter Paper
The specifications are important data for reference when using filter paper in the laboratory. Considering about the applicability, some filter paper is processed by special production procedures.
For example, when testing nitrogen content in blood in the application of medicine inspection, nitrogen-free filter paper must be used. When referring to capacity, because solid particles which are collected during the process of filtration will block the micropore on filter paper, the more intensive the micropore is, the higher the capacity the filter paper has.
On the other hand, there are two key specifications of filter paper. One is filtration features; another is physical properties. Specifically, filtration features include air permeability, airlock, the maximum diameter of micropore and average micropore size. Physical properties include fixing quantify, thickness, deflection, depth of the corrugated, bursting strength, resin content, and so on.
In detail, fix quantify refers to the mass per square meters of filter paper. Thickness refers to the thickness of filter paper excluding the depth of the corrugated. Airlock refers to the resistance of filter paper to the airflow. Air permeability refers to the air amount per unit time under certain areas and certain pressure. Deflection refers to the non-deformability of filter paper.
The specifications of Hawach filter paper for qualitative filter paper products can be found in the national standard (GB l 515). The aperture is about 80 μ 120 μ m, 30 μ m 50 μ m, and 1 μ 3 μ m, respectively. Hawach filter paper is committed to providing high filtration accuracy, which refers to the retention ability of filter paper to particles of a certain size, the size of a tiny sphere that can retain or filter out 50%, the resin content is usually from 10% to 30%, the depth of the grove to be pressed to enhance the stiffness of the filter paper in the longitudinal direction is usually 0-2 mm, and the maximum pressure that can be tolerated on the unit area of the filter paper is greatly enhanced by superior materials and delicate structure.
Steps for Operation
1. Fold the filter paper in the shape of the 90-degree round core. Then, divided into three layers on one side, and open the other side of the filter paper to form a funnel shape.
2. Put into the funnel, pour some clear water into the funnel mouth, contact the soaked filter paper with the inner wall of the funnel, and pour out the rest of the clear water.
3. Place the funnel with filter paper on the funnel frame for filtration, lower the beaker in the neck of the funnel, and keep the tip of the funnel on the wall of the receiving container.
5. When the liquid needing to be filtered is injected into the funnel, the right-hand holds the liquid beaker, the left-hand hold the glass rod, the lower end of the glass rod is close to the lower surface of the funnel, and the liquid cannot exceed the height of the filter paper in the funnel.
6. When the liquid passes through the filter paper and flows down the funnel neck, check if the liquid is running along the wall of the cup and pour it to the bottom of the cup.