利用β沸石纳米簇和曲拉通TX-100分别作为骨架构筑前驱物和孔道导向剂,在酸性介质中通过(NoH+)Cl-S+组装机制合成了蠕虫状孔道排列的AlMSU介孔材料,并借助测试手段对其进行了系统表征。结果表明:制备体系盐酸浓度对AlMSU的结构性能、骨架组成及收率有着显著影响。介质酸浓度较低(<0.5mol/L)时所得AlMSU的物化性质较差,而且产物收率低(基于样品粉末质量);而体系酸浓度大于2.5mol/L时将造成部分铝原子从骨架中析出,导致最终产物中铝元素含量显著降低。基于结构性能、骨架组成和样品收率等综合因素,体系酸浓度介于1.5~2.0mol/L时是合成AlMSU介孔材料的合适区间
Abstract
A series of AlMSU mesostructures with wormhole frameworks have been successfully synthesized using pre-assembled zeolite nanoclusters and nonionic TX- 100 as the inorganic precursor and structuredirecting agent, respectively, under acidic conditions. It was shown that, on the basis of careful structural characterization, the acidity of the synthesis medium had a significant impact on the textural characteristics, framework composition and yield of the final mesostructure. Low-quality AlMSU was obtained when the acid concentration was low (about 0.5mol/L). In contrast, most of the beta zeolite nanoclusters were destroyed during the self-assembly process under extremely acidic conditions (e.g., 3.0mol/L). Therefore, an optimal acid concentration between 1.5 and 2.0mol/L is advantageous during the synthesis of AlMSU.
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脚注
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