Synthesis of molecular sieves is studied using the mother liquor of synthesizing SAPO-34 molecular sieve with triethylamine as template. The triethylamine content in the synthetic solution is determined by chromatography. XRD, SEM, TG, XRF, NH3-TPD and N2adsorption-desorption are used to characterize products. Experiments show that a large amount of triethylamine in SAPO-34 synthesis are present in the mother liquor. Content of triethylamine in product is only 5. 35％ of that in raw material. M1 molecular sieve prepared through the mother liquor has a higher degree of crystallinity and the crystal grains are greatly reduced to about 1 μm. Specific surface area and yield are also increased significantly to725. 85 m2·g-1and 83. 36％, respectively, resulting in more mesopores and more silicon atoms entering the framework of molecular sieve to improve its strong acid amount and acid strength effectively. It is found that crystal seeds can replace part of the template for structural orientation during exploring the role of seed crystals in synthesis.%以三乙胺法合成SAPO-34分子筛的母液为模板剂,进行分子筛的合成研究,采用色谱对合成液中的三乙胺含量进行测定,并利用XRD、SEM、TG、XRF、NH3-TPD和N2吸附-脱附对产品进行表征.结果表明,SAPO-34分子筛合成过程中,大量三乙胺残留在母液中,产品中三乙胺含量仅为原料的5.35％.利用母液制备的M1分子筛具有更高的结晶度,晶粒尺寸大幅减小至约1μm,比表面积和分子筛产率也大幅增加,分别为725.85 m2·g-1和83.36％,产生更多的介孔,有更多的硅原子进入到分子筛骨架中,使分子筛的强酸酸量及酸强度得到有效改善.探究晶种在合成过程中的作用发现,晶种能够替代部分模板剂起到结构导向作用.
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