500mL Filter Setup w/Buchner Funnel, Filter Paper & Rubber Stopper
by OnlineScienceMall

With its 500mL borosilicate glass filter flask and 90mm porcelain buchner funnel, this filtration setup is perfect for use in vacuum filtration. Filtration is a technique by which a solid product is separated from an aqueous solution by pulling the liquid through the filter paper. In this setup, a piece of 9cm filter paper is placed in the buchner funnel, and allows the filtrate (liquid) to pass through into the flask, while the precipitate remains on top of the paper. A custom drilled rubber stopper is included with this setup to hold the funnel in place above the flask.

By using a vacuum hand pump (not included) or a vacuum system (not included), the filtrate is much more easily separated from the precipitate, by pulling as much liquid through as possible. There will be some moisture left in the sample, so it is advisable to allow the sample to dry completely before using it in your application. Using a vacuum rather than gravity filtration allows for a variable filtration rate based on the strength of the pump being used, though care must be taken to not use a vacuum strong enough to rip the filter paper or break the flask. This setup is capable of performing gravity filtration in the absence of a vacuum pump or system.

The included hand vacuum pump made of a durable polychloroethylene plastic, and can easily provide a vacuum of 25-27in/Hg by pumping its handle. The pumping rate is about 15ml per stroke. By changing its working mode, the pump can be used to establish air pressure as high as approximately 2 atm. The pump itself is sealed and self lubricated, and comes with approximately 2 feet of clear rubber tubing to attach to the filter flask.

This filtration setup includes one each of the following items:

• 500mL borosilicate glass filter flask
• 90mm buchner funnel
• 9cm filter paper **may need to be lightly wetted with water to fit properly into the buchner funnel
• 1 rubber stopper, custom drilled
• 1 vacuum hand pump (with gauge)