SAPO-34 molecular sieves were synthesized using diethylamine (DEA) as a template. Influencing factors, such as H3PO4 content, H2O content, Al source, and Si source, were investigated. Pure SAPO-34 could be obtained under the following synthesis gel conditions: 0.7 ≦n(P2O5)(Al2O3) < 1.2 and 25 ≦ n(H2O)(Al2O3) ≦ 100. The Al source has a great influence on the resulting sample composition. SAPO-34 could also be synthesized using triethylamine (TEA), morpholine (MOR), and a DEA-TEA mixture as template, respectively. The products were characterized using X-ray diffraction, X-ray fluorescence, scanning electron microscopy, thermogravimetry, and 29Si MAS NMR. The level of silicon incorporation into the SAPO-34 framework decreased in the following order of SAPO-34 (DEA) > SAPO-34 (MOR) > SAPO-34 (TEA). The Si(4Al) contents in the SAPO-34 frameworks followed the order of SAPO-34 (DEA) ≈ SAPO-34 (MOR) > SAPO-34 (TEA).%以二乙胺(DEA)为模板剂,合成了SAPO-34分子筛,详细考察了磷酸用量、水用量以及硅源和铝源等因素的影响.结果表明,在0.7≤ n(P2O5)(Al2O3)≤1.2及25≤n(H2O )( Al2O3)≤100范围内,可以得到纯相SAPO-34分子筛,铝源对所得样品的组成影响较大.同时,采用三乙胺(TEA)、吗啉(MOR)以及二乙胺-三乙胺(DEA-TEA)混合模板剂合成了SAPO-34,通过X射线衍射、X射线荧光分析、扫描电镜、热重和29Si固体核磁共振等手段对所得样品进行了表征.结果显示,不同模板剂促使硅进入SAPO-34骨架的能力顺序为SAPO-34 (DEA)＞ SAPO-34 (MOR)＞ SAPO-34 (TEA); SAPO-34骨架中所能容纳的最大Si(4Al)含量顺序为SAPO-34 (DEA)≈SAPO-34 (MOR)＞ SAPO-34 (TEA).
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