Cytiva's Whatman Grade 52 is a general-purpose filter paper for quantitative analysis in Büchner funnel and other vacuum filtrations. The acid-hardened surface and low ash content enable efficient precipitate recovery.Manufactured from high-quality cotton linters and treated to remove trace metalsHigh wet-strength and chemical resistanceNominal particle retention of 7 µmMedium flow rate (Herzberg filtration speed 235 s)High purity (0.015% ash maximum)Compatible with Hirsch or Büchner funnel applicationsCytiva's business offers three grades of hardened low ash filter paper. All three are designed for use in Hirsch and Büchner funnel applications and can be customized for an exact fit.Büchner funnel vacuum filtrationThe quality of analysis resulting from vacuum filtration using a Hirsch or Büchner funnel relies on using a high-quality filter that avoids introducing artifacts into measurement. Cytiva's Grade 52 hardened filter paper is acid-treated to prevent fiber shredding during vacuum filtration or precipitate collection.