The properties of bentonite clay of having a good ion exchange capacity (CEC), selectivity and regenerability have generated interest for its use as an adsorbent. Moreover, this type of clay is abundant in Brazil, especially in the Northeast, where bentonites occur superimposed on other mineral deposits of great commercial interest, such as gypsum. This fact could help reduce the costs of extraction of minerals in these deposits. In general, bentonite is a low-cost material, thus enabling its use in wastewater treatment.