Synthesis of Zr-MCM-41 by the assistance of sodium chloride in the self-generated acid conditions

Zr-MCM-41 materials were synthesized by the hydrothermal method in the presence of ZrOCl2 and NaCl. The characterization results showed that Zr was highly dispersed in the tetrahedral environment of silica framework. In the synthesis process, the self-generated acidity by the hydrolysis of ZrOCl2 acted as the catalyst for TEOS hydrolysis. In order to form the ordered structure of Zr-MCM-41, the addition of NaCl in the synthesis gel was essential and the optimum NaCl/Si molar ratio was 1.0. The ordering of Zr-MCM-41 was also influenced by the content of Zr, which decreased gradually with the increase of Zr content.