Important pointers during vacuum filtration
The vacuum filtration creates a negative pressure at the filtrate outlet as a driving force for filtration. It is mainly used for vacuum filtration in the production process of chemical medicine, petroleum and other industries. It has the advantages of a lightweight, convenient installation and maintenance, and easy operation and so on.
The vacuum filtration process is a method of dehydrating wastewater sludge by using the pressure difference between the atmosphere and the vacuum. There are suction filter and vacuum pump in HAWACH vacuum filtration.
Stainless steel multi-continuous vacuum pumping device:
1. It can process multiple samples at the same time. It not only has no pollution for each other but also improve work efficiency;
2. The stainless steel filter is easy to be autoclaved and resistant to high temperature and corrosion.
1. It adopts high-quality glass, which is clear and transparent, without bubbles and with even wall thickness.
2. The special hard high-quality glass material’s temperature difference is up to 280℃.
3. It has good pressure resistance and can be used for high temperature and high-pressure sterilization.
4. This product has a fast flow rate, good grinding standard, and good sealing performance.
5. Dimensions and specifications conform to international standards and can be matched with different brands.
A vacuum filtration, no matter a suction filter or vacuum pump is usually faster than a simple conical funnel. However, when performing a vacuum filtration, there are several points that have to be considered.
1. To work with reduced pressure, special attention has to be paid to the equipment used, such as the glassware should not have any cracks, and the filter flask and the vacuum trap are clamped securely. The thick-walled tubing tends to act like a whip sometimes and slams the filter flask into the hotplate or other metal objects, or just flips it over.
2. The filter flask and the vacuum trap consist of heavy-walled glassware. Also, the thick-walled tubings should be used as well.
3. Vacuum filtration cannot do without a vacuum trap. To keep the trap clean to prevent something from getting sucked in there.
4. Vacuum filtration requires funnels with a flat surface. Moisten the filter paper with the solvent that makes up the solution, and make sure that it adheres well to the bottom. Startup the vacuum and then slowly pour the solution into the funnel.
5. When you place a funnel on top of the filter flask, use a neoprene adapter or rubber stopper to obtain a good seal.
6. After completing the filtration, remove the tubing from the filter flask before you turn off the vacuum.
7. Vacuum filtration is often not suitable for solvents with low boiling points i.e. diethyl ether, dichloromethane or boiling solvents. The solvent evaporates in the vacuum and dissolved solids precipitate, clogging up the pores of the filter paper.
8. If you have a very fine precipitate, it is advisable to use some filter aid like diatomaceous earth or Celite, which will prevent the holes of the filter paper will get clogged up too fast.