Ahlstrom's qualitative grades of filter paper are, by definition, recommended for use in analytical methods, which determine or identify particulate constituents of a mixture irrespective of the amount present. Qualitative filter papers are often used in routine separation work that still requires high purity and consistent performance.
Ahlstrom offers a complete range of low ash filter papers for general laboratory work that provides you with the correct combination of particle retention, filtration speed, loading capacity and wet-strength. All our qualitative grades consist of > 95% super refined a-cellulose and linter fibers.
Key Features
- Quantitative analysis
- Low ash content 0.06%
- Untreated
- High wet-strength
- Consistent performance
- Wet-strengthened grades available
- Custom cut
- Bulk packaging
Ahlstrom 601: 2.5µm – Medium Speed
This grade covers a wide range of laboratory applications and is used for clarifying liquids and for rapid filtration of coarser precipitates such as lead sulfate, lead chromate, calcium oxalate, calcium carbonate, aluminum phosphate, barium carbonate and beryllium hydroxide. Ahlstrom 601 can be found in soil analysis, seed testing and in air pollution to collect dust-laden air and is also commonly used in the food industry to separate foodstuffs from associated liquid or extracting liquid.
Environmental Laboratory Applications:
ASTM E1963-09.A2 Standard Guide for Conducting Terrestrial Plant Toxicity Tests: Root Elongation
Seeds are incubated under controlled conditions in petri dishes with filter paper, such as Grade 601, prior to measuring the root length to determine if a potentially toxic substance has affected the growth rate.
STM 2710.H Tests on Sludges: Time-to-Filter
This simpler measurement correlates with the capillary suction time measured in STM 2710.G. Either Grade 601 or 642 may be used.
STM 5510B Aquatic Humic Substances: Diethylaminoethyl (DEAE) Method
Humic substances are a major portion of organic matter within soil. In this method they are concentrated through column chromatography on DEAE cellulose prior to measurement. The filter used for the preparation of the DEAE is Grade 601.
STM 6651 Glyphosate Herbicide
If suspended matter is present, then the sample is filtered through Grade 601 before being tested for the presence of the herbicide glyphosate.
STM 8310.D Ciliated Protozoa: Growth Inhibition Test
Ciliates can be used to evaluate water and soil quality. Grade 601 is used while preparing the culture.
Mining Laboratory Applications:
ASTM E738-11 Determination of Aluminum in Iron Ore
This procedure calls for a medium textured qualitative filter for aluminum determination. Grade 601 is ideal.
ASTM E945 Zinc Determination in Iron Ore
The zinc is extracted from the ore and precipitated, then collected on Grade 601.
ASTM D3177-02 Total Sulfur in the Analysis Sample of Coal and Coke
There are two filtration stages in this procedure. The first stage requires a qualitative filter to remove the nondissolved portion of the digested material. Grade 601 is recommended for this step. The second step requires a quantitative filter for collecting and
measuring barium sulfate precipitate. Grade 94 is recommended for this step.
STM 2710.H Tests on Sludges: Time-to-Filter
This simpler measurement correlates with the capillary suction time measured in STM 2710.G. Either Grade 601 or 642 may be used.
Construction Laboratory Applications:
ASTM D806-96 Cement Content of Soil/Cement Mixtures
The cement content of a dry soil/cement mixture is determined with this procedure. There are several steps, all of which require filter paper. The first extraction is done with Hydrochloric acid; Grade 601 is recommended. The filtrate is precipitated and
filtered with Grade 54. Again the filtrate is treated and re-filtered with Grade 601. The final precipitate step is filtered with Grade 94.