Currently water pollution constitutes a great challange, and activated carbon is a common adsorbent used to remove hazardous contaminants. Unfortunately, it is a non-selective process. The main object of this study was the use of montmorillonite clays, which can offer both an alternative and a selective process. The adsorption measurement of p-aminobenzoic acid on montmorillonite clays showed a real potential for removing hazardous contaminants waste such as pesticides and chlorophenols. The results showed that the determination of aromatic amines remained dependent on some parameters such as pH, temperature and aqueous concentrations.