Qualitative and quantitative filter papers for the clarification and purification of samples for analysis. Available in a range of sizes, counts, grades, and formats such as circles, sheets, and folded. Often made from cellulose or woven nylon.
Supports accurate analysis in applications sensitive to very low levels of background contamination. Whatman™ Quantitative Filter Paper: Grade 40 Circles are additionally useful in gravimetric analysis where ash content might affect weight measurements of combusted samples.
Saves time required to fit circles into conical funnels. Whatman™ Grade 2V Folded Qualitative Filter Papers provide medium flow and nominal particle retention rating of 8µm at a higher filtration speed.
Covers a wide range of laboratory applications and is frequently used for clarifying liquids. Whatman™ Qualitative Filter Paper: Grade 1 Circles are widely used standard grade filter papers for routine applications with medium retention and flow rates.
Use for quantitative air pollution analysis as a paper tape for impregnation when determining gaseous compounds at high flow rates or for quantitative air pollution analysis. Whatman™ Quantitative Filter Paper: Grade 41 Circles are commonly used in preparing samples for metal analysis after nitric acid digestion.
Specifically developed for measuring the Ignition Strength (IS) of Cigarettes. Whatman™ Qualitative Filter Paper Circles - Grade 2 for IS Measurement are manufactured under strict control; each lot is tested and certified as meeting the requirements of ASTM E2187.
Filters and retains course particles for monitoring air pollution. Whatman™ Qualitative Filter Paper: Grade 4 Circles are used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.
Covers a wide range of laboratory applications and is frequently used for clarifying liquids. Whatman™ Qualitative Filter Paper: Grade 1 Sheets are widely used standard grade filter paper for routine applications with medium retention and flow rates.
Recommended when fast filtration of a gelatinous precipitate for gravimetric analysis is performed on a strongly acidic or alkali solution. Whatman™ Quantitative Filter Paper: Grade 541 Circles are acid hardened cellulose filters, which reduces ash to an extremely low level.
Retains and absorbs more than Grade 1 filters, with a corresponding increase in filtration time. Whatman™ Qualitative Filter Paper: Grade 2 Circles are used for monitoring specific contaminants in the atmosphere and in soil testing.
Supports collection of coarse and gelatinous precipitates with minimal fiber shredding, even when wet. Whatman™ Grade 54 Quantitative Filter Paper has a hard, smooth surface to sustain vacuum and suction filtration.
Use as a gravimetric filter during analysis of metals in acidic or alkaline solutions and in the collection of hydroxides. Whatman™ Quantitative Filter Paper: Grade 540 Circles acid-treated surface prevents tearing during filtration and allows the user to scrape precipitates from the paper.