Particles+Extraction Soong

Description and working steps

Preparation

  • 600 ml 0.05M K2SO4
  • Shaker, centrifuge
  • 200 glass beads
  • 900 ml 0.5% Na-HMP solution
  • 2mm sieve, 63 um sieve
  • 40 aluminum pans
  • Bottles (50ml) for WSEOM

Day 1:

  • Weigh out 6g of 2mm sieved oven dried soil into 50ml centrifuge tubes (record weights).
  • Add exactly 30 ml of 0.05 M K2SO4
  • Shake for 1 hr
  • Centrifuge for 30 minutes at 1000g
  • Pour off WSEOM fraction
  • Freeze WSEOM fraction and eventually freeze dry
  • Add 10 glass beads to non-soluble fraction and 30 ml 0.5% sodium-hexametaphosphate
  • Shake on reciprocal shaker for 18 hrs
  • Pre-weigh all pans
  • Oven dry a sample of initial soil, to get moisture content

Day 2:

  • Stack 2mm sieve over 63 um sieve over a pan
  • Rinse sample over sieves, collect glass beads on 2mm sieve and POM fraction on 63 um sieve
  • Pour POM fraction and MEOM fraction into pre-weighed aluminum pans
  • Dry POM and MEOM in oven at 110 °C for 24 hours or until dry

Day 3-4:

  • Weigh dry POM and MEOM fractions + pan
  • Scrape out fractions into a storage container

Initial Aim

Advantages

Disadvantages

References

The method is unpublished.