We demonstrate a sonication procedure for the removal of structure-directing micellar templates from mesoporous MCM-41. The method uses a 28 KHz ultrasound in an alcoholic solvent for disrupting micellar aggregation of the surfactant molecules, cetyltrimethylammonium bromide, which have filled the pores of the as-synthesized MCM-41. The majority (93%) of the surfactant molecules are removed out from the powder MCM-41 within a 15 min one-step sonication at a moderate temperature of 40°C. The structural and textural characterization techniques reveal that the resulted surfactant-free MCM-41 exhibits higher features compared to that of those obtained using the conventional calcinations approaches. The surfactant molecules are released into alcohol and can be recovered for reuse. This study provides an easy, cost-effective, mild and useful method for template removal from mesoporous materials at conventional conditions.

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Ultrasound waves were successfully applied for the removal of the template from mesoporous MCM-41 molecular sieve. The method uses 28 KHz ultrasound irradiation in a methanol solvent for disrupting the micellar aggregation of the surfactant molecules, cetyltrimethylammonium bromide, which fill the pores of as-synthesized MCM-41. After 15 min sonication at the moderate temperature of 40 °C, the majority of surfactant molecules had been removed from powder MCM-41. The template removal rate using ultrasound irradiation (15 min) is faster than the rate obtained via thermal calcination. In addition, a perfect hexagonal pore structure was obtained after template removal using ultrasound irradiation, according to characterization using X-ray diffraction (XRD) and nitrogen adsorption analyses, while high temperatures during calcination cause shrinkage that affected the surface properties of the materials. In the present procedure, the surfactant molecules are released into methanol and can be recovered for reuse. The effectiveness of the sonicationprepared MCM-41 as an adsorbent was confirmed by the adsorption of methylene blue (MB).