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Features
*Quantitative Filter Papers
Acid Hardened Grades
Expert treatment of filter paper by strong mineral acid
after manufacture brings important benefits. The ash level is
significantly reduced by the removal of trace metals, as the table below
shows.
Strong When Wet
Another advantage of this concentrated acid treatment is
that the paper becomes extremely strong, particularly when wet. The
progressive reduction in ash content can readily be seen by the sequence.
- Qualitative Grade: 0.06% ash
- Ashless Grade: 0.007% ash
- Hardened Ashless Grade: 0.006% ash
The surface of these hardened grades becomes very tough
and smooth, and the effectiveness of precipitate removal by scraping is
greatly increased.
*Qualitative Grade No. 1 shown for comparison
purposes. All results expressed as µg/g.
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