Synthesis Mesoporous Molecular Sieve MCM-41 With Iron Ore Tailings

Mesoporous molecular sieve MCM-41 is usually synthesized with pure chemicals, such as silicon dioxide,sodium silicate, tetraethoxysilane, etc, which are toxic and expensive. Looking for cheap and non-toxic raw materials is urgent. The iron ore tailings with high content of silicon can be silicon source of the MCM-41.In this paper, the research progress about the synthesis method, practical applications of the MCM-41 are reviewed. Hydrothermal and microwave crystallization methods are used to synthesize the MCM-41. The effects of preparative process parameters on the properties of the resulted materials were systemically investigated, and the possible formation mechanism was suggested. The resulted samples were characterized by variety of techniques including XRD, SEM, TEM, and TG-DTG.The results showed that in the process of hydrothermal synthesis, 0.15: 1 was the optimum mole rate of CTAB/SiO2, 11 was the optimum gel pH, 130℃was the optimum hydrothermal nucleation temperature, and 60 h was the optimum nucleation time. In the process of microwave synthesis, when the microwave nucleation power was 50℅, the optimum gel pH was 9, the optimum microwave nucleation time was 40 min, and the optimum mole rate of CTAB/SiO2 was 0.30: 1.Heavy metal ions were used as adsorbents to investigate adsorption performance of the resulted samples. The data denominated that Heavy metal ions were absorbed quantitatively to the samples. Most of the absorption rates were more than 80%.A series of studies including the comprehensive utilization of iron ore tailings,synthesis of MCM-41,adsorption of heavy metals ion studied in this project, which was not only finding an inexpensive silicon source for the MCM-41, a feasible way for the transformation of iron tailings, but also providing an experimental basis for the separation of heavy metal ions in wastewater with molecular sieve.