170135_inorganicventures_flipping

14.2 Ashing

Ashing Techniques: Sulfated Ash

§ Sulfated Ashing involves treatment of the sample a5er charring using an open flame with sulfuric acid. § The char is we;ed using the minimum amount of sulfuric acid and then brought to dryness. § Before placing in a muffle furnace the char should be heated to >400 C. § A;empt to keep the ashing temperature between 450 and 500 C. § Sulfated ashes generally discourage the formaFon of refractory oxides during muffling making dissoluFons easier. § Do not sulfate samples for Ba or Pb trace analysis.

14.3 Ashing

Ashing Techniques: Wet Ashing

§ Wet Ashing is treatment of the sample with a moderate amount of sulfuric acid before charring. § Charring is performed using an open flame. § Liquid samples tend to foam. § A