Filter Paper Grade: 4, 240 mm:A standard grade filter used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.
These cellulose filters are used in qualitative analytical techniques to determine and identify materials. Prepleated qualitative filters are also available, which give improved flow rate and increased loading capacity compared to equivalent flat filters.
Grade 4: 25 micro-m
Extremely fast filtering with excellent retention of coarse particles and gelatinous precipitates such as ferric hydroxide and aluminum hydroxide. Very useful as a rapid filter for routine clean-up of biological fluids or organic extracts during analysis. Used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.
|Parameter||Grade 4 Qualitative Filter Paper Standard Grade, circle, 240 mm|
|Typical Particle Retention in Liquid||25 micro-m|
|Nominal Thickness||210 micro-m|
|Typical water flow rate2||247 ml/min|
|Nominal Basis Weight||92 g/m2|
|Nominal Air Flow Rate||4 s/100 ml/in2|
|Nominal Ash Content||0.06%|
|Typical Trace Element Levels||Aluminium 3.6 micro-g/g Antimony <0.5 micro-g/g Arsenic <0.5 micro-g/g |
Barium <0.5 micro-g/g Boron <1 micro-g/g Calcium 27.5 micro-g/g
Chromium 1 micro-g/g Copper 0.9 micro-g/g Iron 13.7 micro-g/g
Lead <0.5 micro-g/g Magnesium 21 micro-g/g Manganese <0.5 micro-g/g
Mercury <0.5 micro-g/g Potassium 6.2 micro-g/g Silicon 8.8 micro-g/g
Sodium 32.3 micro-g/g Zinc 58.3 micro-g/g
|Application||Used when high flow rates in air pollution monitoring are required and |
the collection of fine particles is not critical.