Surface waters are easily within reach of contamination. This pollution comes from wastewater from various industries such as textiles, pharmaceuticals and food. Generally, these waters not only contain colorants, they are also made up of different salts such as Na₂SO₄, NaCl and Na₂CO₃. All these pollutants are harmful to the environment and especially to health because they are highly carcinogenic. Among the various technologies applicable for the removal of this type of pollutant, adsorption is one of the most used methods to treat effluents contaminated with colorants due to its low energy cost. The use of flocculants based on natural polymers is the best option for treating industrial wastewater. Chitosan is a natural cationic polymer obtained by deacetylation of chitin. Its linear structure and high molecular weight make it a suitable water treatment agent.