| 二丙胺的结构微调对磷酸铝分子筛晶化过程影响的凝胶组成依赖性 |
| Initial-Gel-Composition-Dependence of Dipropylamine-Structure-Fine-Tuning Influence on the Crystallization Pathways of Aluminophosphate Molecular Sieve |
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| 摘要: 以二丙胺异构体（二正丙胺DPA和二异丙胺D-iPA）为结构导向剂，在200℃加热2组反应原料物质的量之比不同的初始凝胶，合成出了高结晶度的磷酸铝分子筛AlPO4-11。利用X射线粉末衍射分析、元素分析等表征手段，研究了凝胶的晶化过程和液相的pH值以及Al和P的浓度演化。初始凝胶各组分物质的量之比为nAL2O3：nP2O5：nDPA/D-iPA：nH2O=1.0：1.0：1.2：75时，以DPA为结构导向剂，晶化过程中无中间相生成，而以D-iPA为结构导向剂时，晶化过程中生成了具有12元环孔道结构的磷酸铝分子筛AlPO4-5中间相；初始凝胶各组分物质的量之比为nAL2O3：nP2O5：nDPA/D-iPA：nH2O=1.0：1.0：1.0：75时，以DPA为结构导向剂，晶化过程中生成了具有18元环孔道结构的磷酸铝分子筛VPI-5中间相，而以D-iPA为结构导向剂时，晶化过程中同时出现了VPI-5及AlPO4-5两种中间相。表明对于同一种有机胺，凝胶物质的量之比的改变影响了其结构导向效应。理论计算结果显示质子化的DPA及D-iPA中N原子上的电荷有差异，表明有机胺的结构微调影响其结构导向效应，但该影响依赖于凝胶组成。 |
| 关键词: 沸石 磷酸铝 结构导向效应 晶化途径 中间相 |
| 基金项目: 国家自然科学基金（No.21571075，21320102001，21621001）、国家重大研发计划（No.2016YFB0701100）和高等学校学科创新引智计划（No.B17020）资助项目。 |
| Abstract: The structure-directing effect of dipropylamine isomers, i.e., di-n-propylamine (DPA) and diisopro-pylamine (D-iPA), was investigated. By heating the initial gels with certain composition at 200℃ for 24 h, highly crystalline aluminophosphate molecular sieve AlPO4-11 was obtained. The crystallization processes were investigated using X-ray diffraction, elemental analysis and pH value measurement. For the crystallization process of the initial gel with nAL2O3:nP2O5:nDPA/D-iPA:nH2O=1.0:1.0:1.2:75, no intermediate phase was formed when the DPA was used as the structure-directing agent, whereas intermediate phase of aluminophosphate molecular sieve AlPO4-5 was observed when the D-iPA was used as the structure-directing agent. For the crystallization process of the initial gel with nAL2O3:nP2O5:nDPA/D-iPA:nH2O=1.0:1.0:1.0:75, intermediate phase of aluminophosphate molecular sieve VPI-5 was formed when the DPA was used as the structure-directing agent, whereas intermediate phases of both VPI-5 and AlPO4-5 were observed when the D-iPA was used as the structure-directing agent. Theoretical calculation showed that the charge on the N of the protonated DPA was different with that on the N of the protonated D-iPA. The results indicate that the structure-directing effect of amine can be affected by the composition of the initial gel and the fine-tuning of the structure of amine can influence its structure-directing effect. However, such influence is affected by the composition of the initial gel. |
| Keywords: zeolites aluminophosphate structure-directing effect crystallization pathway intermediate phase |
| 投稿时间：2017-03-15 修订日期：2017-06-11 |
| 摘要点击次数: 1569 |
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| 王子,闫文付,徐如人.二丙胺的结构微调对磷酸铝分子筛晶化过程影响的凝胶组成依赖性[J].无机化学学报,2017,33(9):1595-1602. |
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