The main objective of this work was to synthesize the MCM-41 material from optimized protocols. In the second step, the pore size and the specific surface area of the parent material was increased by the incorporation of swelling agents (long chain carbon amines N-N, Dimethyl-dodecylamine -DMDDA-) in post-synthesis. Then the selective extraction of the amine and the calcination allowed us to obtain materials with pore sizes and even larger surfaces than those of the starting materials (parent materials). The adsorbents, identified as MCM-41 (P), DMDDA-41 (A), DMDDA-41 (B), DMDDA-41 (C) and MCM-41 (P/C), were characterized regarding their texture, mesoscopic ordering and chemical surface and finally their adsorption capacity was evaluated using two diffrent dyes (anionic: Orange II sodium and cationic: Janus Green B). The results obtained during the adsorption study show the efficiency of these materials, in particular the (amine and calcined) materials for decolorizing aqueous media contaminated with organic dyes. The kinetic studies and the adsorption isotherms were carried out to clarify the method of fixing each of the two dyes on the two materials tested. The experiments showed that the amine material had a maximum capacity for fixing Orange II (221.06 mg / g) (anionic dye), whereas for a maximum adsorption capacity (455.23 mg / g ) Of the Janus GB (cationic dye), the calcined material is more efficient.