Whatman Laboratory Filtration

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 1: 11 µm
The most widely used filter paper for routine applications with medium retention and flow rate. Extended range of sizes includes 10 to 500 mm diameter circles and 460 x 570 mm sheets. This filter is also available in theFilterCup, this is a convenient, disposable 70 mm filter funnel with a 250 ml capacity molded from polypropylene with an integral, heat bonded filter (catalog number 1600-001).

This grade covers a wide range of laboratory applications and is frequently used for clarifying liquids. Traditionally the grade is used in qualitative analytical separations for precipitates such as lead sulfate, calcium oxalate (hot), and calcium carbonate.

In agriculture, it is used for soil analysis and seed testing procedures. In the food industry, Grade 1 is used for numerous routine techniques to separate solid foodstuffs from associated liquid or extracting liquid and is widely used in education for teaching simple qualitative analytical separations.

In air pollution monitoring, using circles or rolls, atmospheric dust is collected from airflow and the stain-intensity measured photometrically. For gas detection, the paper is impregnated with a chromogenic reagent and color formation quantified by optical reflectance.

Grade 2: 8 µm
Slightly more retentive than Grade 1 with a corresponding increase in filtration time (i.e., slightly slower filtration speed). More absorbent than Grade 1. In addition to general filtration in the 8 µm particle size range, the extra absorbency is utilized, for example, to hold soil nutrient in plant growth trials. Also used for monitoring specific contaminants in the atmosphere and in soil testing. Also available prepleated asGrade 2V.

Grade 3: 6 µm
Double the thickness of Grade 1 with still finer particle retention and excellent loading capacity; more precipitate can be held without clogging. The extra thickness gives increased wet strength and makes this grade highly suitable for use in Büchner funnels. The high absorbency is particularly valuable when the paper is used as a sample carrier. This filter is also available in the FilterCup. This is a convenient, disposable 70 mm filter funnel with a 250 ml capacity molded from polypropylene with an integral, heat bonded filter (catalog number 1600-003).

Grade 4: 20-25 µm
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.

Grade 5: 2.5 µm
The maximum degree of fine particle filtration in the qualitative range. Capable of retaining the fine precipitates encountered in chemical analysis. Slow flow rate. Excellent clarifying filter for cloudy suspensions and for water and soil analysis. Also available prepleated as Grade 5V.

Grade 6: 3 µm
Twice as fast as Grade 5 with similar fine particle retention. Often specified for boiler water analysis applications.

Grade 591: 7-12 µm
A thick filter paper with very high loading capacity for fast filtration of medium to coarse precipitates. Offers high absorbency and increased wet strength. Also available prepleated as Grade 591 ½.

Grade 595: 4-7 µm
Very popular, thin filter paper, medium-fast with medium to fine particle retention. Used for many routine analytical applications in different industries, (e.g., particle separation from food extracts or filtration of solids from digested environmental samples, e.g., for ICP/AAS analysis). Also available prepleated asGrade 595 ½.

Grade 597: 4-7 µm
A medium fast filter paper with medium to fine particle retention. Used for a wide variety of analytical routine applications in different industries like food testing (e.g., determination of fat content) or removal of carbon dioxide and turbidity from beverages (e.g., beer analysis). Available prepleated as Grade 597 ½.

Grade 598: 8-10 µm
A thick filter paper with high loading capacity. Combines medium retention with medium-fast to fast filtration speed. Also available prepleated as Grade 598 ½.

Grade 602 h: < 2 µm
A dense filter paper for collecting very small particles and removing fine precipitates. Used in sample preparation, e.g., in the beverage industry for residual sugar determination, acidic spectra, refractometric analysis, and HPLC. Available prepleated as Grade 602 h ½.

For qualitative wet strengthened papers see Qualitative filter papers – wet strengthened grades

Whatman Laboratory Filtration

Typical Properties – Qualitative Standard Filter Grades
GradeDescriptionParticle
retention
in liquid (µm)		Filtration speed
(approx.)
herzberg (s)		Air flow
(s/100 ml/in2)		Typical
thickness
(µm)		Basis weight
(g/m2)
1Medium flow11*15010.518088
2Medium flow8*24021190103
3Medium flow, thick6*32526390187
4Very fast20 to 25*373.720596
5Slow2.5*14209420098
6Medium to slow3*71535180105
591Medium fast, thick7 to 12†455.9350161
595Medium fast, thin4 to 7†80–15068
597Medium fast4 to 7†140–18085
598Medium fast, thick8 to 10†50–320140
602 hSlow, dense< 2†375–16084
* Particle retention rating at 98% efficiency
† Approximate values

 

Ordering Information – Qualitative Filter Papers – Standard Grades
Catalog NumberDescription
Grade 1
1001-6508Grade 1 circles, 10 mm, 500/pk
1001-0155Grade 1 circles, 15 mm, 500/pk
1001-020Grade 1 circles, 20 mm, 400/pk
1001-325Grade 1 circles, 25 mm, 100/pk
1001-025Grade 1 circles, 25 mm, 400/pk
1001-329Grade 1 circles, 30 mm, 100/pk
1001-030Grade 1 circles, 30 mm, 400/pk
1001-032Grade 1 circles, 32 mm, 100/pk
1001-042Grade 1 circles, 42.5 mm, 100/pk
1001-047Grade 1 circles, 47 mm, 100/pk
1001-055Grade 1 circles, 55 mm, 100/pk
1001-070Grade 1 circles, 70 mm, 100/pk
1001-085Grade 1 circles, 85 mm, 100/pk
1001-090Grade 1 circles, 90 mm, 100/pk
1001-110Grade 1 circles, 110 mm, 100/pk
1001-125Grade 1 circles, 125 mm, 100/pk
1001-150Grade 1 circles, 150 mm, 100/pk
1001-185Grade 1 circles, 185 mm, 100/pk
1001-240Grade 1 circles, 240 mm, 100/pk
1001-270Grade 1 circles, 270 mm, 100/pk
1001-320Grade 1 circles, 320 mm, 100/pk
1001-385Grade 1 circles, 385 mm, 100/pk
1001-400Grade 1 circles, 400 mm, 100/pk
1001-500Grade 1 circles, 500 mm, 100/pk
1001-813Grade 1 sheets, 26 x 31 mm, 1000/pk
1001-824Grade 1 sheets, 75 x 100 mm, 500/pk
1001-917Grade 1 sheets, 460 x 570 mm, 100/pk
1001-918Grade 1 sheets, 460 x 570 mm, 500/pk
1001-931Grade 1 sheets, 580 x 680 mm, 100/pk
1001-932Grade 1 sheets, 580 x 680 mm, 500/pk
1001-929Grade 1 sheets, 600 x 600 mm, 100/pk
1600-001FilterCup 70 (requires FilterCup stem, catalog number 1600-900), 25/pk
Grade 2
1002-042Grade 2 circles, 42.5 mm, 100/pk
1002-047Grade 2 circles, 47 mm, 100/pk
1002-055Grade 2 circles, 55 mm, 100/pk
1002-070Grade 2 circles, 70 mm, 100/pk
1002-090Grade 2 circles, 90 mm, 100/pk
1002-110Grade 2 circles, 110mm, 100/pk
1002-125Grade 2 circles, 125 mm, 100/pk
1002-150Grade 2 circles, 150 mm, 100/pk
1002-185Grade 2 circles, 185 mm, 100/pk
1002-240Grade 2 circles, 240 mm, 100/pk
1002-270Grade 2 circles, 270 mm, 100/pk
1002-320Grade 2 circles, 320 mm, 100/pk
1002-385Grade 2 circles, 385 mm, 100/pk
1002-500Grade 2 circles, 500 mm, 100/pk
1002-6691Grade 2 sheets, 430 x 680 mm, 500/pk
1002-917Grade 2 sheets, 460 x 570 mm, 100/pk
1002-931Grade 2 sheets, 580 x 680 mm, 100/pk
1002-929Grade 2 sheets, 600 x 600 mm, 100/pk
Grade 3
1003-323Grade 3 circles, 23 mm, 100/pk
1003-055Grade 3 circles, 55 mm, 100/pk
1003-070Grade 3 circles, 70 mm, 100/pk
1003-090Grade 3 circles, 90 mm, 100/pk
1003-110Grade 3 circles, 110 mm, 100/pk
1003-125Grade 3 circles, 125 mm, 100/pk
1003-150Grade 3 circles, 150 mm, 100/pk
1003-185Grade 3 circles, 185 mm, 100/pk
1003-240Grade 3 circles, 240 mm, 100/pk
1003-320Grade 3 circles, 320 mm, 100/pk
1003-917Grade 3 sheets, 460 x 570 mm, 100/pk
1600-003FilterCup 70 (requires FilterCup stem, catalog number 1600-900), 25/pk
Grade 4
1004-027Grade 4 circles, 27 mm, 400/pk
1004-042Grade 4 circles, 42.5 mm, 100/pk
1004-047Grade 4 circles, 47 mm, 100/pk
1004-050Grade 4 circles, 50 mm, 100/pk
1004-055Grade 4 circles, 55 mm, 100/pk
1004-070Grade 4 circles, 70 mm, 100/pk
1004-090Grade 4 circles, 90 mm, 100/pk
1004-110Grade 4 circles, 110 mm, 100/pk
1004-125Grade 4 circles, 125 mm, 100/pk
1004-150Grade 4 circles, 150 mm, 100/pk
1004-185Grade 4 circles,185 mm, 100/pk
1004-240Grade 4 circles, 240 mm, 100/pk
1004-270Grade 4 circles, 270 mm, 100/pk
1004-320Grade 4 circles, 320 mm, 100/pk
1004-400Grade 4 circles, 400 mm, 100/pk
1004-912Grade 4 sheets, 130 x 190 mm, 500/pk
1004-917Grade 4 sheets, 460 x 570 mm, 100/pk
1004-930Grade 4 sheets, 580 x 580 mm, 100/pk
Grade 5
1005-325Grade 5 circles, 25 mm, 100/pk
1005-042Grade 5 circles, 42.5 mm, 100/pk
1005-047Grade 5 circles, 47 mm, 100/pk
1005-055Grade 5 circles, 55 mm, 100/pk
1005-070Grade 5 circles, 70 mm, 100/pk
1005-090Grade 5 circles, 90 mm, 100/pk
1005-110Grade 5 circles, 110 mm, 100/pk
1005-125Grade 5 circles, 125 mm, 100/pk
1005-150Grade 5 circles, 150 mm, 100/pk
1005-185Grade 5 circles, 185 mm, 100/pk
1005-240Grade 5 circles, 240 mm, 100/pk
1005-320Grade 5 circles, 320 mm, 100/pk
1005-550Grade 5 circles, 550 mm, 100/pk
Grade 6
1006-042Grade 6 circles, 42.5 mm, 100/pk
1006-070Grade 6 circles, 70 mm, 100/pk
1006-090Grade 6 circles, 90 mm, 100/pk
1006-110Grade 6 circles, 110 mm, 100/pk
1006-125Grade 6 circles, 125 mm, 100/pk
1006-150Grade 6 circles, 150 mm, 100/pk
1006-185Grade 6 circles, 185 mm, 100/pk
1006-240Grade 6 circles, 240 mm, 100/pk
Grade 591
10311387Grade 591 sheets, 580 x 580 mm, 250/pk
Grade 595
10311610Grade 595 circles, 110 mm, 100/pk
10311611Grade 595 circles, 125 mm, 100/pk
10311612Grade 595 circles, 150 mm, 100/pk
10311687Grade 595 sheets, 580 x 580 mm, 100/pk
Grade 597
10311862Grade 597 circles, 12.7 mm, 1000/pk
10312040Grade 597 circles, 42.5 mm, 100/pk
10311804Grade 597 circles, 45 mm, 100/pk
10311807Grade 597 circles, 55 mm, 100/pk
10311808Grade 597 circles, 70 mm, 100/pk
10311809Grade 597 circles, 90 mm, 100/pk
10311810Grade 597 circles, 110 mm, 100/pk
10311811Grade 597 circles, 125 mm, 100/pk
10311812Grade 597 circles, 150 mm, 100/pk
10311814Grade 597 circles, 185 mm, 100/pk
10311820Grade 597 circles, 240 mm, 100/pk
10311822Grade 597 circles, 320 mm, 100/pk
10311897Grade 597 sheets, 580 x 580 mm, 100/pk
10311887Grade 597 sheets, 580 x 580 mm, 500/pk
Grade 598
10312209Grade 598 circles, 90 mm, 100/pk
10312287Grade 598 sheets, 580 x 580 mm, 250/pk
Grade 602 h
10312611Grade 602 h circles, 125 mm, 100/pk
10312612Grade 602 h circles, 150 mm, 100/pk
10312614Grade 602 h circles, 185 mm, 100/pk
10312620Grade 602 h circles, 240 mm, 100/pk
FilterCup Stem
1600-900FilterCup stem, 1/pk