A simple and fast sonication procedure to remove surfactant templates from mesoporous MCM-41

Abstract

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.

An Eco‐Friendly, Tunable and Scalable Method for Producing Porous Functional Nanomaterials Designed Using Molecular Interactions

“…Calcination increased the surface area of silica similar to the acid treatment (Figure 5); however, the pore‐size analysis showed that larger pores were generated by calcination compared to A or even A+C silica (Figure S2). This degradation of the pore structure, which was only evident for calcined and not for A or A+C silica, indicates that the thermal decomposition of PEHA during calcination causes degradation of the pore structure, an issue that has been reported for calcination of other templated materials 16. Therefore, it can be concluded that room‐temperature acid treatment is as effective as calcination in purification, in addition to avoiding the degradation of delicate structures during purification owing to the mild nature of this method compared to conventional techniques.…”

An energy-efficient route to the rapid synthesis of organically-modified SBA-15 via ultrasonic template removal

“…19 Ultrasonication has also been shown an effective means to remove organic micelles during MCM-41 synthesis. 20 Here we demonstrate that ultrasonication is also an efficient method to remove Pluronic triblock co-polymer templates from at 40 °C. Subsequently, 8.2 cm 3 of tetraethylorthosilicate (TEOS) was added, and after 45 min reaction, 0.76 ml of 3mercaptopropyl)trimethoxysilane (MPTS) and 3.8 cm 3 of H 2 O 2 simultaneously added and the solution stirred for 24 h. The mixture was then aged at 100 °C for a further 24 h, and 5 the resultant solid filtered and washed three times with water and finally dried overnight at 80 ºC.…”

“…Amongst the most widely exploited of all mesoporous silicas is the hexagonal close-packed SBA-15, first reported by Zhao et al in 1998, 5 which possesses 20 large pore diameters spanning 5-30 nm, coupled with excellent thermal, mechanical and chemical resistance properties which underpin its application in catalysis, [6][7][8][9][10][11] enzyme immobilisation 12 and separation science. 13 Since its discovery, SBA-15 has received over 100,000 citations in the 25 scientific literature, and now features in approximately 800 new publications every year (Figure 1).…”

Synthesis of Tricyclopentadiene Over Nanoporous MCM-41 Catalysts

“…Comparing the crystal structure of metal oxide/MCM-41 catalyst with the result of Jabariyan et al it was confirmed that the catalysts used in this study has specific peaks corresponding to MCM-41. 18 The crystal structure of metal oxide/MCM-41 catalysts has three diffractional peaks of 2.2 , 3.8 , and 4.4 at 2 , which could correspond to (100), (110), and (200), respectively. The acid characteristics of metal oxide/MCM-41 catalysts were analyzed with NH 3 -TPD.…”