Whatman Grade 4 Qualitative Filter Papers are a standard grade, high flow rate filter paper. They are useful in qualitative analytical separations when fast flow is required and the collection of fine particles is not critical. These cellulose filters are used in qualitative analytical techniques to determine and identify materials (e.g., in air pollution monitoring).

Specifications
• Application: Used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.
• Grade: Grade 4
• Grade Type: Standard
• Material: Cellulose
• Nominal Ash Content†: 0.06%
• Nominal air flow rate: 4 s/100 ml/in
• Nominal basis weight: 92 g/m
• Nominal thickness: 210 µm
• Typical Particle Retention in Liquid††: 25 µm
• Typical Trace Element Levels: Aluminum 3.6 µg/g Antimony <0.5 µg/g Arsenic <0.5 µg/g Barium <0.5 µg/g Boron <1 µg/g Calcium 27.5 µg/g Chromium 1 µg/g Copper 0.9 µg/g Iron 13.7 µg/g Lead <0.5 µg/g Magnesium 21 µg/g Manganese <0.5 µg/g Mercury <0.5 µg/g Potassium 6.2 µg/g Silicon 8.8 µg/g Sodium 32.3 µg/g Zinc 58.3 µg/g
• Typical water flow rate†††: 247 ml/min

†Ash is determined by ignition of the cellulose filter at 900 DEG C in air.
††Particle retention rating at 98% efficiency.
†††For 9 cm diameter
††††U.S. Sales Only
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