Page 130 - Feed Lab

Suguna Management System Ver 1.0 / SOP / FQL / P2 - 41 Page 1 of 1

41. Estimation of Sodium Bentonite Assay

portions at intervals of two minutes, to 100 ml of
SCOPE
solution of sodium lauryl sulphate (one percent m/v)
To estimate the assay of sodium Bentonite.
contained in 100ml measuring cylinder. Now please
check the swelling volume of Bentonite after 24 hours.
1. Differential Free Swell Test
Two samples of Bentonite powder weighing 10gm 3. Test Method of Gelling Time 100%
each are taken. One is put in a 50 cc graduated glass Take 2.5 gm of Bentonite in 25ml of distilled water
cylinder containing kerosene oil (a non polar liquid). The contained in 2.5mm diameter of test tube. Shake
other sample is put in a similar cylinder containing vigorously for 60 sec. check its gelling properties with
distilled water. Both the samples are left undisturbed for time. Till the test tube to check its instant gelling
24 hours and then their volumes are noted, properties.
Note: Pure sodium Bentonite always shows more than Note: Pure Sodium Bentonite always gives high gelling
500% DFS value. properties.

2. Test For Swelling Power
Add 2.0 gm of Bentonite in 20 approximately equal

CALCULATION
The differential free swell (DFS) is expressed as

Bentonite volume in water - Bentonite volume in kerosene
DFS = --------------------------------------------------------------------------
Bentonite volume in Kerosene X 100

Prepared by : Approved by :
118 Director - Technical