This manual describes the step‑by‑step procedure for soil four‑acid digestion using the PerkinElmer SPB graphite digestion instrument.
The document provides a complete operating procedure for the SPB graphite digestion instrument, covering sample preparation, reagent addition, heating stages, acid evaporation, and final dilution. It is intended for laboratory personnel performing soil digestion prior to analysis by AAS, ICP‑OES, or ICP‑MS.
Key steps include weighing the soil sample, adding appropriate volumes of aqua regia, hydrofluoric acid and perchloric acid, controlling temperature ramps from 110 °C up to 175 °C, and ensuring consistent acid volumes across samples and blanks. Safety notes emphasize working in a fume hood and avoiding high‑temperature acid additions that could cause explosions. This manual is written in Chinese.
| Cover material and temperature limit | PP, up to 130 °C; PTFE optional for higher temperature |
|---|---|
| Sample weight for AAS/ICP‑OES | 0.2500–0.5000 g |
| Sample weight for ICP‑MS | 0.1000 g |
| Aqua regia volume for 0.5 g sample | 6 mL |
| Hydrofluoric acid volume | 4 mL |
| Perchloric acid volume | 2 mL |
Weigh 0.2500 to 0.5000 g of soil sample for AAS or ICP‑OES.
Add 6 mL of aqua regia to a 0.5 g sample.
Heat the tube at 120 °C for 4 hours after adding HF.
The cover is made of PP and can withstand up to 130 °C; PTFE can be used for higher temperatures.