The value of pH varies depending on the
activation of bentonite, by increasing the concentration of sulfuric acid,
increases the acidity. With the rise of the pH value, we have a continuous increase of ion
exchange capacity of bentonite, so high values of pH, we have a high capacity
to exchange cations. The ion exchange capacity of natural samples of Karaçeva
bentonite, varies according to the depth of drilling, with increase of the
percentage of activation, have significant increase of ion exchange capacity
for all investigated samples. By experimental measurements, it was found that
the Karaçeva bentonite has good ion exchange properties.
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