Whatman Filter Paper Qualitative Grades

Qualitative filter papers come in various grades, each suited to different needs across multiple industries. Here’s a quick overview of some common grades, their properties, and typical applications:

Filter Paper Grade 1

• Sizes Available: Circles (10 mm to 150 cm)
• Properties: 11µm particle retention, 180 µm thickness, 87 g/m² weight, 0.06% ash content
• Applications: Widely used in routine applications for medium retention and flow rate. Ideal for clarifying liquids, soil analysis, seed testing, and atmospheric dust collection.

Filter Paper Grade 2

• Sizes Available: Circles (42.5 mm to 500 mm)
• Properties: 8µm particle retention, 190 µm thickness, 97 g/m² weight, 0.06% ash content
• Applications: Offers higher retention than Grade 1, suitable for plant growth trials and contaminant monitoring in air and soil.

Filter Paper Grade 3

• Sizes Available: Circles (23 mm to 320 mm)
• Properties: 6µm particle retention, 390 µm thickness, 185 g/m² weight, 0.06% ash content
• Applications: With double the thickness of Grade 1, Grade 3 is ideal for holding more precipitate without clogging, especially in Büchner funnels.

Filter Paper Grade 4

• Sizes Available: Circles (27 mm to 400 mm)
• Properties: 25µm particle retention, 210 µm thickness, 92 g/m² weight, 0.06% ash content
• Applications: Best for fast filtration of coarse particles, used in air pollution monitoring and routine biological fluid clean-up.

Filter Paper Grade 5

• Sizes Available: Circles (25 mm to 320 mm)
• Properties: 2.5µm particle retention, 200 µm thickness, 100 g/m² weight, 0.06% ash content
• Applications: Offers maximum fine particle retention, making it ideal for chemical analysis and clarifying suspensions.

Filter Paper Grade 6

• Sizes Available: Circles (42.5 mm to 240 mm)
• Properties: 3µm particle retention, 180 µm thickness, 100 g/m² weight, 0.06% ash content
• Applications: With high absorbency and increased wet strength, Grade 6 is perfect for boiler water analysis and similar tasks.