Synthesis of MCM-41 with a Phosphonium Template

Cetyltrimethyl phosphonium bromide was successfully used as a template in the synthesis of MCM-41. The material was characterized by small-angle X-ray diffraction, transmission electron microscopy, nitrogen adsorption, and 29Si, 13C, and 31P solid-state NMR spectroscopy. These results were compared with those of MCM-41 prepared with the conventional cetyltrimethylammonium bromide surfactant showing that the material is highly ordered. Interestingly, the materials showed a “temporary” hydrothermal stability induced by residual P2O5 produced by the calcination. NMR measurements on the reaction mixture showed that 31P can be used as an excellent probe for in situ investigation of the formation mechanism.