ASTM D546-99 pdf free.Standard Test Method for Water-Soluble Acidity or Alkalinity of Paper.
Reagent grade chemicals shall beused in all tests.Unless otherwise indicated, it is intended thatall reagents shall conform to the specification of the Committeeon Analytical Reagents of the American Chemical Society,where such specifications are available.7 Other grades may beused,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.
Hydrochloric or Sulfuric Acid,Standard Solution(0.01N)Prepare and standardize a 0.01N solution of hydro-chloric acid (HCl) or sulfuric acid (H SOq).Calculate normal-ity to four decimal places.Unless otherwise indicated, referencesto water shall be understood to mean freshly boiled and cooledreagent water，Type I or ll, as described in SpecificationD 1193.Allow the prepared test specimen to reach moistureequilibrium with the atmosphere of the balance case.Weigh two 5-g portions to the nearest 1 mg forextraction.
At the same time, and using the third prepared sample,determine the moisture content of the material in accordancewith Test Method D 644.
Transfer the weighed portions of sample (see 10.2) totwo 500-mL Erlenmeyer flasks and add 250 mL of boilingwater to each flask. In some cases，the fibers absorb waterslowly and tend to float on the surface of the water.This maybe avoided by first adding small portions of the water andshaking well until the fibers are thoroughly saturated.To a third 500-mL Erlenmeyer flask add 250 mL ofboiling water. This constitutes the blank. Carry this blankthrough all the remaining steps of the procedure.After the water is added,affix a condenser to eachflask.The air condenser may be used if an oil or water bathregulated to 100°C is used. When using a hot plate, the West orAllihn type condenser (see 6.5.2) must be used.
Place the flask with condenser aflixed on the heatsource.Allow a few minutes for the sample to come to the bathtemperature, or, in the case of the hot plate, to begin to gentlyboil. Maintain temperature for 60 5 min swirling occasionally.At the end of this period, pour the contents of the flaskinto a Buchner funnel without other filtering medium. Wash thefibers remaining in the flask into the Buchner funnel with 10mL of hot distilled water.Wash the fibers in the Buchner funnel with 25 to 50mL of hot distilled water. Apply suction to complete thefiltration and cool the extract rapidly in a stoppered Erlenmeyerflask.As soon as the extract reaches room temperature,quantitatively transfer it to a 400-mL beaker.ASTM D546 pdf download.