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以氢氧化已烷双铵(R(OH)2)和溴化六甲双铵(HMBr2)为模板剂分别合成了ITQ-13、B-ITQ-13、Al-ITQ-13分子筛,采用XRD、SEM-EDX、N2吸附-脱附、FT-IR、MAS NMR等手段对合成的分子筛进行表征,比较了两种模板剂合成的ITQ-13分子筛的性质,以溴化六甲双铵(HMBr2)为模板剂,在碱性加晶种的条件下,反应3~10 d合成出了ITQ-13以及含杂原子B、Al的ITQ-13分子筛,降低了合成的成本.以溴化六甲双铵为模板剂合成的ITQ-13晶貌有块状和球形针状堆积混合晶貌组成,孔道宽,晶粒因堆积形成的介孔居多.量子力学中的密度泛函理论(DFT)计算Ge、B、Al同晶取代Si在ITQ-13分子筛9个不同T位的分布,T5位对于ITQ-13分子筛的特殊骨架结构形成具有重要作用,对于骨架的电荷平衡以及几何约束力都有重要作用.Al原子容易替代的位置是位于九元环和十元环孔口相交处的T6、T7位.
ITQ-13, B-ITQ-13 and Al-ITQ-13 molecular sieves were synthesized by using hexamethonium hydroxide (R (OH) 2) and hexamethonium bromide (HMBr2) The molecular sieves were characterized by FT-IR, EDX, N2 adsorption-desorption, FT-IR and MAS NMR. The properties of ITQ-13 molecular sieve synthesized by the two templates were compared. Using hexamethonium bromide (HMBr2) , ITQ-13 and ITQ-13 molecular sieves containing heteroatoms B and Al were synthesized under the conditions of alkaline addition and seeding for 3 ~ 10 d, which reduced the cost of synthesis.Using hexamethonium bromide as a template The synthesized ITQ-13 crystal has a mixture of massive and spheroidal needle-like inclusions with wide pores and the majority of mesopores formed by the accumulation of the grains. Density functional theory (DFT) in quantum mechanics calculates the content of Ge, B, Al isotopic replacement of Si in the ITQ-13 molecular sieve at nine different T-position distribution, T5 position ITQ-13 zeolite for the formation of a special skeleton structure plays an important role in the charge balance of the skeleton and geometry binding forces have an important role in Al atoms The easy-to-replace location is T6, T7 at the intersection of a nine-ring and ten-ring orifice.