Whatman
Grade 42 Ashless Filter Paper for Instrumental Analysis, 55mm Circle, 100/Pk SKU: 1442-055

Quantitative Ashless Filter Paper - 1442-055

Gravimetric procedures in regulated laboratories require documented ash content that can be reported alongside analytical results for compliance verification. Acid washing removes metallic ions that could interfere with trace element determinations following ignition of the loaded filter. Standardized manufacturing protocols produce papers with retention and flow characteristics that remain constant from the first batch to the last.

Key Filter Paper Characteristics

• Acid washing process removes metallic contaminants that could interfere with trace element determinations after ignition.
• Standard construction provides the absorption and wicking characteristics that gravity-based filtration protocols require.
• Controlled fiber density balances rapid filtration with complete precipitate capture for efficient quantitative determinations.
• Designed for gravimetric determinations where the filter paper is ashed or ignited as part of the analytical measurement step.
• Acid-washed cellulose construction produces ash content below 0.01%, meeting the blank value requirements of quantitative gravimetric methods.

If you're transitioning from qualitative screening to quantitative gravimetric work, the documented ash content above confirms this paper's suitability. Under these conditions, uniform fiber density across the sheet area ensures your precipitate capture remains consistent from center to edge. Take control of your sample preparation variables and ensure that your data reflects the true nature of your work, rather than the quality of your consumables.

Diameter

55mm

Flow Speed

Slow

Folded/ Fluted/ Pleated

No

Grade

42

Hardened (Yes/ No)

No

Material

Cellulose Fiber

Nominal Ash Content (%)

<0.007%

Nominal Basis Weight (g/ m²)

100g/m²

Pack Count

100

Particle Retention

2.5um

Pore Size (µm)

2.5

Qualitative/ Quantitative

Quantitative

Sterility

Nonsterile

Wet Strengthened (Yes/ No)

No

Wettability

Hydrophilic

• Sulfate Gravimetry - Retains barium sulfate precipitate for ignition-based sulfate quantification in water and industrial samples.
• Lead Quantification - Captures lead sulfate precipitate for gravimetric determination in environmental and industrial samples.
• Silica Determination - Captures dehydrated silica for gravimetric analysis in cement, geological, and industrial raw material testing.
• Zinc Analysis - Collects zinc ammonium phosphate precipitate for ignition-based quantification in metallurgical and water testing.
• Aluminum Analysis - Collects aluminum hydroxide precipitate for ignition and weighing in metallurgical and environmental methods.
• Phosphate Gravimetry - Collects magnesium ammonium phosphate precipitate for ignition to pyrophosphate in soil and fertilizer analysis.