Table 1: Properties of the bentonite.

Chemical analysis

L.o.I. (%) 7.50 ± 1.00
SiO2 (%) 71.00 ± 1.00
Al2O3 (%)14.00 ± 1.00
Fe2O3 (%)0.70 ± 0.10
TiO2 (%)0.05 ± 0.01
CaO (%)1.10 ± 0.30
MgO (%)3.20 ± 0.20
Na2O (%)0.25 ± 0.05
K2O (%)1.00 ± 0.10

Mineralogical analysis

Montmorillonite (%)80
Cristobalite-opal C (%)17
K-feldspar (%)3
Plagioclase (%)Trace

Properties

Cation exchange capacity (meq/100 gr)85.0 ± 5.0
CaCO3 (%)0
Swelling (mL/2 gr)8.0 ± 2.0
Sedimentation (72 hours) (mL)10
Sintering point (°C)1200
Bulk density (gr/lt)800 ± 30
Clumping testPositive
Clump weight (gr)55 ± 5
Water absorbtion (%)90 ± 5
Water absorbtion duration (sec)max. 65
NH3 adsorption (ppm)40
Bleaching—original(Tonsil equivalent)0.6
Bleaching—Acid activated (Tonsil equivalent)0.7
pH (8% solid) 8.5
Grit content (+75 μm) (%)<4
Color White
Lightness93 ± 1
Moisture (%)<30