Matter
- Name
- Ca-exchanged montmorillonite SWy-2 size-fraction <0.1 µm
- Family
- mineral
- Database
- Experimentalists
- Parent matter
- Na-Montmorillonite SWy-2
- Origins
- natural terrestrial
- Provider
- Clay Minerals Laboratory, Institute of Geological Sciences, Polish Academy of Sciences
- Local reference code
- CaSWy2_LSD
- Body name
- Earth
- Preparation
- extracted components
- Method
- Monominerallic sample extracted by removal of carbonates, organics, and Fe-(oxy-)hydroxides by a sequence of acetic acetate buffer, hydrogen peroxide, and buffered sodium dithionite treatments, followed by washing in deionized water, size separation by centrifugation, ionic exchange by five washings with 0.5 M CaCl2 and subsequent dialysis in deionized water and drying at 60C. Sample was stored at room temperature and relative humidity
- Phase type
- solid
- Component type (group)
- mineral (silicate mineral)
- Texture
- aggregated grains
- Type of porosity
- particulate
- Texture
- clay-like
- Grain sizes
-
Grains Size min Size max Size median Size width Size mass fraction Grain shape #1 0.1 ${\mu}m$ 1.0 $\pm$ 0.05 platy - Size method
- Size-fraction was separated in a centrifuge (Stoke's Law) but not verified
- Title
- Purification, size separation, and cation exchange
- Matters
- Materials
- Matter
- Ca-exchanged montmorillonite SWy-2 size-fraction <0.1 µm (this matter)
- Processing steps
-
Step Date Type Process Changes #1 2013-03-01 mechanical Dry sieving at 400µm mesh Removal of coarse fraction (above 0.4 mm #2 2013-03-01 chemical Reaction of 30 g of a sample with 150 ml of hydrogen peroxide for 30 min at 40C. Repeated 3 times. Removal of organic matter #3 2013-03-02 chemical Reaction with 200 ml of Na-acetate buffer (ph 4.5 to 5.5) at 90C for 30 min Removal of carbonates #4 2013-03-03 chemical Reaction with 2g sodium dithionite in 200 ml of sodium citrate - sodium bicarbonate solution at 75C Removal of free Fe(hydro)oxides #5 2013-03-04 fluid physical Washing with deionized water Removal of excess adsorbed cations and anions #6 2013-03-05 mechanical centrifugagion in deionized water Separation of <0.1 micron fraction according to Stoke's Law #7 2013-03-06 chemical Reaction with 100 ml of 0.5 M CaCl2 repeated five times Exchange of exchangeable cations for Ca #8 2013-03-07 fluid physical Dialysis in deionized water. Water was changed until conductivity of water dropped below 1 microsiemens Removal of excess adsorbed cations and anions #9 2013-03-11 thermal Drying in an oven at 60C Drying of a sample #10 2013-03-12 mechanical Crushing in an agate mortar Disintegration of a sample in order to create powder