What is CEC?
CEC is the cation exchange capacity of the montmorillonite clay. The CEC can be determined by titration by using an ammonium acetate method. (Titration Method). The CEC is a measure of the amount of cations available on the montmorillonite clay. Typically the cation on natural montmorillonite is Na+ or Ca++. These cations can be exchanged with an onium ion to make an organoclay by an ion exchange reaction. To make an organoclay at stoichiometry one equivalent of onium ion is exchanged with one equivalent of cation on the clay. The ion exchange does not have to be run at stoichiometry as the clay can be under or over exchanged.
