|
SBA-15 mesoporous molecular sieve having a high specific surface area, pore structure and pore easy to adjust the rules, thermal stability and hydrothermal stability, good surface and easy modification, etc., so in catalysis and adsorption separation chemistry and other fields have a great potential applications. This thesis includes the following four parts: The first part of the study under acidic conditions to triblock copolymer PE0 20 - PPO 70 - PEO 20 (P 123 ) as template, TEOS as silicon source, hydrothermal synthesis SBA-15 mesoporous molecular sieves. The effects of reactant ratio and crystallization temperature, crystallization time and stirring speed and other factors on the impact of synthetic zeolite, and through XRD, BET, FT-IR, TEM, SEM and other methods were used to characterize the samples. The results showed that: the synthesis of a large stir speed, the crystallization time of three days, the templating agent, silica source, hydrochloric acid and water, the molar ratio of nP 123 : nTEOS: nHCI: nH 2 < / sub> O: = 1:60:35 ~ 350:9666, the synthesized samples with long-range ordered hexagonal mesoporous structure, crystallization temperature increase is conducive to a larger aperture synthetic samples. The second part of the study in the synthesis of microporous composite molecular sieve Naβ/SBA-15 and its preliminary characterization. The results show that the obtained composite zeolite small angle XRD pattern of the diffractive angle of the diffraction region area and large peaks occur simultaneously, corresponding to the hole and a microporous phase. IR spectra and scanning electron microscopy revealed significantly different composite zeolite micropores mechanical mixtures. The third part to titanocene as titanium source, preliminary investigation of SBA-15 surface grafted titanium Ti-SBA-15 zeolite synthesis, structural characterization results showed that after Ti-grafted SBA-15 remains a highly ordered hexagonal pore structure, most of the Ti source to zeolite surface with silicon-bonded hydroxyl groups, only a small part of the lost. The fourth part of the KNO 3 / AISBA-15 load-zeolite catalysts used in catalytic dimethyl carbonate (DMC) and propanol transesterification synthesis of dipropyl carbonate (DPC) response. Were investigated preparation of the carrier, the active ingredient loading amount, the catalyst activation temperature on the catalytic activity. The results show that the synthesis of this catalyst transesterification of DPC has high catalytic activity. When the molar ratio DMC: propanol = 1:4, the amount of catalyst reaction system 3% of the total mass of the reaction temperature is 90 ℃, reaction time 6h time, DPC selectivity of 96.1%, the yield was 90.2%.
|