Filter Paper
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 and sheets, they are often made from cellulose or nylon.
Filter papers are familiar laboratory consumables often used with a conical funnel or similar device to filter and retain solids, particulates, and other materials from aqueous solutions, suspensions, solvents, and other liquids. Filter papers may be manufactured from natural cellulose, nylon, or glass or quartz fibers. They are typically available as pre-cut circles of various diameters, which may be folded into pleats, quadrants, or pyramids. Some filter papers are also sold as sheets or rolls that can be cut to size as needed.
Filter papers may be categorized as qualitative or quantitative. Qualitative filter papers are used for general purpose filtration applications where subsequent analysis is not critical. Quantitative filter papers (ashless papers) are intended for more exacting analytical work and may be weighed or otherwise processed after use. They are made from low-linting fibers that are typically acid-hardened during their manufacture to provide high wet strength and chemical resistance, and are pre-rinsed with demineralized water for extra purity.
Most filter papers are also graded numerically according to pore size, which in turn infers other parameters such as flow rate, retention, thickness, weight, and burst strength, that constrain and prescribe their application.
What is Filter Paper Used for?
• General applications: research laboratories, clinics, and educational settings
• Analytical applications: precipitant and particulate removal prior to further analysis or assay
• Industrial applications: foods and beverages, cosmetics, and gravimetric analysis of cements, clays, and iron and steel products
• Environmental applications: water, soil, or atmospheric sample analysis
Sartorius Stedim Diatomaceous Earth Filter Paper
This filter grade is made of cellulose and diatomaceous earth and offer a much better separating capability than pure cellulose papers at the same rate of filtration. This grade quickly retains the finest particles at high flow rates.
Cytiva Whatman™ Quadrant Folded Filter Papers
Saves users valuable time and provides ease of use when undertaking repetitive or multiple analyses
Sartorius Qualitative Grade 1291 Filter Papers
These qualitative filter papers are essentially used for analytical purposes and routine analyses, whenever no gravimetric analyses are required. They are wet-strengthened and can be used for pressure and vacuum filtration.
Sartorius Quantitative Grade 1288 Filter Papers
These qualitative filter papers are essentially used for analytical purposes and routine analyses, whenever no gravimetric analyses are required. They are wet-strengthened and can be used for pressure and vacuum filtration.
Sartorius Quantitative Grade 389 Filter Papers
These filter papers are used for quantitative and gravimetric analyses as well as for pressure or vacuum filtration. They are made out of 100 % cotton linters with an α-cellulose content of > 98 % and are acid-washed to make the papers ashless and achieve high purity.
Sartorius Quantitative Grade 388 Filter Papers
These filter papers are used for quantitative and gravimetric analyses as well as for pressure or vacuum filtration. They are made out of 100 % cotton linters with an α-cellulose content of > 98 % and are acid-washed to make the papers ashless and achieve high purity.
Cytiva Whatman™ Environmental pollution analysis papers with gravimetric filter suited for quantitative analysis of soil and air.
Environmental pollution analysis papers with gravimetric filter suited for quantitative analysis of soil and air.
Cytiva Whatman™ Glass Microfiber Filters with Binder, Grade GF 10
Made from borosilicate glass and strengthened with an organic binder to provide high mechanical stability
Cytiva Whatman™ Grade 93 Wet Strength Qualitative Filter Papers - Circles
Wet-strengthened qualitative circles
Cytiva Whatman™ Grade 91 Wet Strengthened Qualitative Filter Papers - Sheets
High wet strength due to the addition of chemically stable resin
Cytiva Whatman™ Grade 92 Glass Microfiber Filter Paper
Improves performance and longevity of equipment. Whatman™ Grade 92 Glass Microfiber Filter Paper can be used for a wide range of applications.
Cytiva Whatman™ Qualitative Filter Paper: Grade 1 Sheets
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.
Cytiva Whatman™ Application-Specific Filters, Grade 72
Designed for air pollution monitoring of radioactive iodine in medical and nuclear installations
Cytiva Whatman™ Quantitative Filter Paper: Grade 42 Sheets
Filters and retains extremely small particles. Whatman™ Quantitative Filter Paper: Grade 42 Sheets are suitable for processes that require ashing.
Cytiva Whatman™ Seed Testing Papers
Grade 181 seed testing circles