LARK® Quantitative Filter Paper, Ashless, Grade 40

LARK® GRADE 40  quantitative filters are designed for gravimetric analysis and the preparation of samples for instrumental analysis. They are available in three formats designed to meet your specific needs. The classic general purpose ashless filter paper with medium speed and retention. Typical applications include gravimetric analysis for numerous components in cements, clays, iron, and steel products; as a primary filter for separating solid matter from aqueous extracts in general soil analysis, quantitative determination of sediments in milk and as a pure analytical grade clean-up filter for solutions prior to AA spectrometry. Also used as a high-purity filter in the collection of trace elements and radionuclides from the atmosphere.

The typical grade for quantitative tasks, is coarser precipitates, such as lead-, iron, and silver sulfide alkali carbonates, foodstuff, and soil analysis. Filtration Speed Fast, Retention – coarse and gelatinous precipitates retain particles >15 µm, filter hydroxides, and metallic aerosols, used in environmental monitoring, determining\silica content in steel. Grade 40 Filtration speed Medium, Retention Crystalline retains medium particles ( 5 to 10 µm) such as CaCo3 , PbSo4 , CaCo4, MnCo3 , ZnS, AgCl.