Actions:

#01. Gasket assembly on Büchner filter
#02. Placement of the filter on the vacuum flask
#03. Placement of the glass fiber filter (1 µm)
#04. Weighing of the material to be filtered
#05. Sample transfer
#06. Activation of the vacuum pump
#07. Measurement of filtration time
#08. Filtration

Büchner filtration is a laboratory technique used to separate solids from liquids through a porous filter, often made of porcelain, placed inside a special funnel. To speed up the process, a vacuum is applied, which facilitates the passage of the liquid through the filter.

The Büchner funnel, as it is commonly called, features a flat perforated surface on which filter paper is placed. The vacuum—usually generated by a water pump—draws the liquid through the filter and collects it in the flask below, leaving the solid residue on the filter paper.
The lower part of the funnel is long and conical, designed to fit securely into a vacuum flask using a rubber or cork gasket to ensure an airtight seal. The pump is connected to the flask through a rubber tube attached to the sidearm of the flask.

Measuring the filtration time helps evaluate the quality of a product: generally speaking, the shorter the filtration time, the better the performance during production (particularly in ceramics, where it helps prevent clogging of filters and nozzles, or blockages in digital printers).
This filtration system is commonly used to isolate purified compounds after recrystallization, or as part of quantitative analyses in analytical chemistry.