Qualitative filter circles, Whatman Grade 4

Filter paper made from pure cellulose for general, analytical, and technical filtration of crystalline precipitations and particulates, with very fast flow rate. Grade 4 qualitative filter papers are useful when fast flow rates are required and the collection of fine particles is not critical, such as with gelatinous precipitates e.g. ferric hydroxide and aluminium hydroxide. Used for qualitative analyses and to collect and identify materials in your sample, or for air pollution monitoring.

Specifications:

• Surface: Smooth
• Particle retention in liquid: 25 µm (98 %)
• Filtration speed: 247 s
• Thickness: 0,21 mm
• Basis weight: 92 g/m²
• Ash content: 0,06 %