Whatman 1441-125 Filter Circles, 125mm Dia, Ashless Grade 41, 100/pk (PN:1441-125)

Grade 41 is designed for quantitative gravimetric analysis involving coarse particles or gelatinous precipitates, such as iron or aluminum hydroxides. It is also widely used in environmental testing, including air and soil pollution analysis workflows.

This fast ashless filter paper offers approximately 20–25 µm particle retention and rapid filtration performance (around 54 sec/100 mL by Herzberg method), making it ideal when high flow rates are needed.

Ashless papers like Grade 41 have extremely low ash content (≤ 0.007%), which minimizes residue after ignition. This is critical for accurate gravimetric measurements and trace metal analysis where contamination must be minimized.

This model features 125 mm diameter cellulose filter circles made from high-quality cotton linters and is supplied in packs of 100. The paper is hydrophilic and optimized for fast quantitative filtration tasks.

Grade 41 is preferred when filtering coarse or bulky precipitates and when speed is more important than very fine retention. For finer particles, laboratories typically choose slower grades (such as Grade 42) with smaller pore sizes.