Montmorillonite is the main bentonite forming mineral which has special characteristics such as suspension, swelling and colloidal properties. It can absorb water to become larger in volume.

Good absorbents are extensively used in industry eithersimply dried or after chemical activation. The chiefconsumer of these clays is the oil refinering industry whichuses them to purify fractionation products of suspendedmatter and as drilling muds.

This study on bentonite shows that mineralogicalcomposition and concetration of Al₂O₃, MgO in montmorillonite are the most important characteristics forchemical activation of bentonite.

In addition to above factors, the temperature, acidconcentration and time are also considered for activation.