Whatman 1454-070 Filter Circles, 70mm Dia, Hardened Low Ash Grade 54, 100/pk (PN:1454-070)

Grade 54 is a quantitative hardened low-ash filter paper designed for fast vacuum or gravity filtration of coarse and gelatinous precipitates. It is commonly used in analytical chemistry, recrystallization workflows, and general laboratory filtration.

Typical specifications include:

Diameter: 70 mm
Particle retention: ~22 µm
Ash content: ≤0.015%
Thickness: ~185 µm
Filtration speed: fast (Herzberg ~39 s)
Pack size: 100 circles

These properties support reliable quantitative filtration performance.

“Hardened” indicates the paper has been acid-treated for high wet strength and resistance to fiber shedding, while “low ash” means it leaves minimal residue after ignition, making it suitable for gravimetric and quantitative analysis.

Grade 54 is optimized for Büchner funnel and Hirsch funnel vacuum filtration, but it can also be used in gravity filtration when fast flow and strong wet strength are required.

This grade performs best with coarse particles, crystalline precipitates, and gelatinous materials where rapid filtration and mechanical strength are important. Its smooth, hard surface helps minimize fiber shedding even when wet.