Take the sample with specified quantity and place it in the specifiedcrucibleOr in a dish
1. Solid sample
Heat slowly until the sample is completely volatilized or carbonized, cool down, wet the residue with 0.5mL sulfuric acid, continue to heat until the sulfuric acid vapor escapes, and burn in a high temperature furnace at 650 ± 50 ℃ to constant weight.
2. Liquid sample
Add 0.25mL of sulfuric acid, heat it in a water bath or electric furnace (do not boil) until the sample is completely volatilized or carbonized, continue heating on the electric furnace until the sulfuric acid vapor is exhausted, and burn it in a high temperature furnace at 650 ± 50 ℃ to constant weight.
3. Samples without or without sulfuric acid
Heat slowly until the sample is completely volatilized or carbonized, and burn it in a high temperature furnace at 650 ± 50 ℃ to constant weight.[1]
calculation
Announce
edit
w: Mass fraction of burning residue (calculated by sulfate), unit:%.
X1: mass of residue and empty crucible or residue and empty dish, unit: g.
X2: mass of empty crucible or empty vessel, unit: g.
