Whatman™ Quantitative Filter Paper, Ashless, Grade 42

The Whatman™ Grade 42 Quantitative Filter Papers are premium ashless cellulose filters designed for high-precision gravimetric analysis and critical laboratory applications. Offering the finest particle retention (~2.5 µm) among all Whatman ashless grades, these filters are ideal for applications requiring maximum clarity, purity, and analytical accuracy.

With an extremely low ash content (≤0.007%) and high chemical purity, Grade 42 filter papers are specifically suited for trace analysis, environmental testing, and instrumental sample preparation, where even minimal contamination can impact results.

Key Features

Finest Particle Retention

• Nominal retention of ~2.5 µm, the finest among Whatman ashless grades
• Effectively removes fine particulates and impurities
• Ideal for sensitive analytical and instrumental workflows

Ultra-Low Ash Content

• Maximum ash content of ≤0.007%
• Ensures minimal residue after combustion
• Critical for accurate gravimetric and elemental analysis

High-Purity Cellulose Composition

• Manufactured from refined cellulose fibers
• Minimizes background contamination
• Suitable for trace element and radionuclide analysis

Designed for Critical Gravimetric Analysis

• Commonly used for precipitates such as:
  • Calcium carbonate
  • Barium sulfate
  • Metastannic acid
• Ensures reliable mass measurements after filtration and ashing

Fine Filtration with Controlled Flow

• Slow filtration speed (Herzberg ~1870 seconds)
• Allows thorough separation of fine particles
• Improves analytical precision in complex samples

Applications

• High-precision gravimetric analysis
• Environmental testing (soil and water filtration)
• Trace element and radionuclide collection
• Sample preparation for ICP, AAS, and other instrumental analysis
• Filtration of fine precipitates and suspensions
• Analytical chemistry and research laboratories
• Industrial quality control and environmental monitoring

Technical Specifications

Available Models and Ordering Information

Workflow Integration

Sample Preparation → Fine Filtration (Grade 42) → Drying / Ashing → Gravimetric or Instrumental Analysis

This ensures:

• Maximum removal of fine particulates
• Minimal background contamination
• Highly accurate analytical results

Unique Advantages

• Finest particle retention among ashless Whatman grades
• Ideal for trace analysis and sensitive instrumentation
• Ultra-low ash content ensures accurate gravimetric results
• High purity supports environmental and elemental analysis
• Reliable performance for critical laboratory workflows
• Wide range of sizes for flexible application

The Whatman™ Grade 42 Quantitative Filter Papers (Ashless) are the gold standard for laboratories requiring maximum filtration precision and analytical accuracy. With their fine retention, ultra-low ash content, and suitability for trace-level analysis, they are indispensable for advanced gravimetric, environmental, and instrumental applications.