Filtering Funnels
Filtering Funnels
Filtering funnels, also known as Buchner and Hirsch funnels, include a cylinder separated from the funnel with a fritted glass disc or perforated plate. Fritted glass disc funnels are immediately ready for use, while perforated plates call for filter paper moistened with liquid to prevent initial leakage.
Vacuum suction then draws the liquid through the filter and into the cylinder. Porcelain filtering funnels are resistant to acids and alkalis, except for hydrofluoric acid, but should not be used in the filtration of extremely corrosive reagents, which can slowly corrode their protective enamel. The funnels are glazed both outside and inside, except the rim, and are autoclavable.
What Is a Buchner Funnel Used for?
Buchner funnels are used in the laboratory for vacuum-assisted liquid filtering. In organic chemistry, these funnels are used to collect recrystallized compounds because they help remove moisture from the final product.
How Does a Buchner Funnel Work?
Buchner funnels consist of an open straight-sided cylindrical chamber that narrows to a tube- or pipe-shaped opening. The tube-like extension can be placed through a stopper, which is then placed into the top of a filtration or Buchner flask. Plastic versions may have a bung hole located at the side of the chamber to which a vacuum may be attached. Buchner funnels are reusable.
What Types of Buchner Funnels Are There?
The bottom of the Buchner funnel chamber may be perforated or contain a separate fritted disc. Filter paper is used for Buchner funnels with perforated lower surfaces. Place the filter paper of the preferred porosity inside the chamber, pre-wet, add the liquid, and apply the vacuum.
Filtration with a Buchner funnel proceeds more quickly than letting the liquid flow simply using gravity. Most Buchner funnels are also rated for a maximum vacuum pressure.
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Filtered Search Results
Fisherbrand™ Porcelain Buchner Funnels with Fixed Perforated Plates
For suction filtration applications
Includes | Fixed perforated plate |
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Product Type | Buchner Funnel |
Quantity | Each |
Material | Porcelain |
For Use With (Application) | Suction filtration applications |
Autoclavable | Yes |
Synthware™ Buchner Filter Funnels
Greener Choice
Offers one or more environmental benefits itemized in the U.S. FTC Green Guides.
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Offers one or more environmental benefits itemized in the U.S. FTC Green Guides.
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Used to filter particulates from a variety of substances
Product Type | Buchner filter funnel |
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Graduated | Yes |
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Material | Polypropylene |
For Use With (Application) | Variety of laboratory applications |
Bel-Art™ SP Scienceware™ Single-Piece Buchner Funnels
One-piece HDPE with sealed-in, polyethylene Fritware™ porous filter plate
Pore Size | 90 to 130μ |
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Description | Fritware™ polyethylene filter |
Max. Temperature (English) | 125°F |
Material | HDPE |
Porosity | Coarse |
Max. Temperature (Metric) | 52°C |
Bel-Art™ SP Scienceware™ Buchner Funnels
Easy-to-clean two-piece, polypropylene with perforated HDPE plastic filter plate
Thermo Scientific™ Nalgene™ Büchner Two-Piece Polypropylene Funnels
Separate the lightweight and durable two-piece polypropylene funnels for easy cleaning. These funnels won't chip, crack or break.
Material | Polypropylene |
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Autoclavable | Yes |
Corning™ PYREX™ Buchner Funnels with Fine Porosity Fritted Disc
Useful where filter paper would be attacked by material being filtered
Includes | Fritted discs |
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Product Type | Buchner Funnel |
Material | Pyrex Glass |
Certifications/Compliance | ASTM E128 |
For Use With (Application) | Useful where filter paper would be attacked by material being filtered |
Thermo Scientific™ Nalgene™ Single Use Analytical Filter Funnels
Perform microbiological QC testing and analysis of water, food/beverage, raw material and finished product with these economical sterile disposable funnels.
For Use With (Equipment) | Filter Manifold, Filtering Flask |
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Material (Membrane) | Cellulose Nitrate |
Diameter (Metric) Filter | 47 mm |
Thermo Scientific™ Nalgene™ Reusable Filter Funnel with Clamp
Designed for use in a wide range of applications, Thermo Scientific™ Nalgene™ filtration hardware and accessories can be used in conjunction with our various lines of filtration devices.
Includes | Sealed-in fritted disc, drip tip and integral No. 2 side hose connection |
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Product Type | Buchner Funnel |
Joint Number | 24/40 |
Material | Borosilicate Glass |
Certifications/Compliance | USP Type I, ASTM E438 Type I, Class A |
DWK Life Sciences Kimble™ Kontes™ Fritted Hirsch Filter Funnels
Directs filtrate through a reduced area frit to concentrate crystal residue for rewashing
Product Type | Hirsch Funnel |
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Material | Borosilicate Glass |
Certifications/Compliance | USP Type I, ASTM E438, Class A |
For Use With (Application) | Directs filtrate through a reduced area frit to concentrate crystal residue for rewashing |
DWK Life Sciences Kimble™ KIMAX™ Buchner Kimflow™ Fritted Disc Funnels
Use where filtrate would attack paper filters and membranes
Includes | Kimflow™ fritted disc, heavy wall stem |
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Product Type | Buchner Funnel |
Material | Borosilicate Glass |
Certifications/Compliance | USP Type I, ASTM E438 Type I, DD-F-776, Class A |
Synthware™ Buchner Funnels with Inner Joint
Greener Choice
Offers one or more environmental benefits itemized in the U.S. FTC Green Guides.
Learn More
Offers one or more environmental benefits itemized in the U.S. FTC Green Guides.
Learn More
For use with filtration techniques.
Product Type | Buchner Funnel |
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Bel-Art™ SP Scienceware™ Buchner Table-Top Funnels, 18 in. (45.7cm) I.D.
Filter large volumes quickly with a polyethylene plastic Table-Top Buchner Funnel.
Material | Polyethylene |
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Bel-Art™ SP Scienceware™ Buchner Table-Top Funnels, 24 in. (61cm) I.D.
Filter large volumes quickly with a polyethylene plastic Table-Top Buchner Funnel.
Height (Metric) | 330 mm |
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Diameter (Metric)Top | 61 cm |
Material | Polyethylene |