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Mesoporous molecular sieve MCM-41 has a large specific surface area, pore size distribution of a single, one-dimensional ordered pore, etc., and therefore, by the extensive attention in the field of catalysis, adsorption. Characteristics of the kaolin in Inner Mongolia is rich in natural resources, good quality, good material A process for the preparation of aluminosilicate zeolites. In this paper, the characteristics of the kaolin in Inner Mongolia as aluminum source, TEOS (TEOS) to complement the silicon source, cetyl trimethyl ammonium bromide (CTAB) as template, using the hydrothermal synthesis method, preparation of aluminum-doped Miscellaneous mesoporous molecular sieve (Al-MCM-41). X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy characterization means the structure of synthetic samples, morphology analysis, preparation conditions on the structure of the product, the thermal stability of the investigated samples and static hydrothermal stability , and carbon monoxide preferential oxidation (CO-PROX) Al-MCM-41 carrier effect a preliminary study. Raw material characterization results show: kaolin ratio of the surface area of 18.44m2 / g, pore volume of 0.05cm3 / g, and average pore diameter of 9.96nm, the main component is triclinic, P1 (1) space group Structure Al4OH8 (Si4O10), the higher degree of crystallinity layered kaolinite, as well as a small amount of iron oxide and titanium oxide. Kaolin calcined in 466.9oC ~ 971.4oC within the to generate activity amorphous aluminosilicate, all aluminum source and part of the silicon source for the hydrothermal synthesis of Al-MCM-41 mesoporous molecular sieves. Investigated kaolin calcination temperature of the raw material silicon to aluminum ratio, reaction temperature, pH value, crystallization time, crystallization temperature, sample roasting methods of preparation conditions on the mesoporous molecular sieve Al-MCM-41 structure. The main factors for the kaolin calcination temperature, the raw material silicon to aluminum ratio, reaction temperature, pH, and crystallization time, crystallization temperature and sample roasting did not affect significantly the structural characteristics of mesoporous molecular sieves, just the structure parameters slightly changes. The synthesis of Al-MCM-41 the optimal preparation conditions: kaolin calcination temperature 550oC, calcined kaolin 2.0g, reaction temperature 45oC, pH value of 10.00, the crystallization temperature of 110oC, crystallization time 72h, calcined at a heating rate of 2oC/min Sample calcination temperature 550oC. Al-MCM-41 was synthesized under the optimized conditions, specific surface area of 580.65m2 / g, the pore volume to 0.54cm3 / g, the average pore size of 3.57nm, the Si / A atomic ratio of 9. Samples with high crystallinity, with a non-uniform distribution of spherical particles, most of the aluminum into the mesoporous molecular sieve framework. The effects of the thermal stability of a sample of Al-MCM-41. With increasing sample calcination temperature, excessive silanols polycondensation, causing part of the the orderly structure collapsed, ordering declined. XRD results show 700oC calcined for 2 hours under the Al-MCM-41 samples can still maintain a good and orderly. The effects of the static thermal stability of the sample of the Al-MCM-41. XRD results show that, when immersed in boiling water for 12 hours, the sample ordering decreased sample hydrothermal stability needs to be further improved. Al-MCM-41 as CO-PROX reaction catalyst carrier feasibility study carrier Al-MCM-41 catalyst structure and catalytic properties affect.
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