Dry Ash Procedure for B & Al

Reagents

  1. 1 N HYDROCHLORIC ACID - Dilute 83.3 mL conc. HCl to 1 L Deionized H2O (dH2O) or 170 mL to 2 liters d H2O).

Apparatus

  1. MUFFLE FURNACE
  2. "HIGH FORM" PORCELAIN CRUCIBLES
  3. 100 mL VOLUMETRIC FLASKS
  4. 13 X 100 mm FLINT GLASS TEST TUBES

Procedure

  1. Weigh 1.000 g sample into "high form" porcelain crucible.
  2. Place sample into furnace and increase temperature gradually until temperature reaches 500oC.
  3. Ash for 1 h after reaching temperature.
  4. Remove sample from furnace and let cool.
  5. Dissolve ash by adding 10 mL 1 N HCl to crucible.
  6. Allow to equilibrate for 15 min.
  7. Quantitatively transfer dissolved ash into 100 mL volumetric flasks.
  8. Wash down sample with dH2O.
  9. Dilute to volume with dH20 and shake.
  10. Place aliquot into ICP test tube.
  11. Record values directly from ICP sheet with no decimal.

Quality Control

  1. Ash NIST peach sample as needed. Run solution along with standards and samples daily. Prior to use, the NIST peach sample should be dried overnight at 80oC and stored in the desiccator.
  2. Check ICP standards at midpoints and end of run.

References

  1. See page Dry Ash Procedure.