模板剂合成ZSM-35动力学模拟计算

通过分子模拟途径,将吡咯烷、乙二胺、正丁胺三种有机模板剂与ＺＳＭ－３５沸石骨架间非成键互作用的能学分析分别于它们的合成实验结果进行对照,论证模板剂与沸石间非键相互作用能与合成速率的关联。发现处于十员环孔道中的上述三种模板剂与ＺＳＭ－３５骨架间非成键互作用能从小到大的顺序与晶化速率从快到慢的顺序一致。     

乙胺分子的多光子电离过程质谱研究

报道了乙胺分子在４４０～４７５ｎｍ波长范围内多光子电离（ＭＰＩ）质谱（ＭＳ）研究结果。碎片离子主要由母体离子碎裂模式产生。母体离子ＣＨ３ＣＨ２Ｎ＋·Ｈ２由经３ｓ里德堡态的（２＋２）共振多光子电离产生后，大部分发生β键断裂，形成ＣＨ２＝Ｎ＋Ｈ２离子，还有一部分再吸收一个光子，通过Ｃ－Ｈ（ＣＨ２）键的断裂产生了ＣＨ３ＣＨ＝Ｎ＋Ｈ２离子。ＣＨ３ＣＨ＝Ｎ＋Ｈ２和ＣＨ２＝Ｎ＋Ｈ２离子最容易发生的碎裂过程是脱去氢分子，分别产生Ｃ２Ｈ４Ｎ＋（分子式）离子和ＣＨ≡Ｎ＋Ｈ离子。     

在小硅化物SiX~m（X＝Be、B、C、N、O、F、Ne，m＝～4－＋2）中分子成键倾向的从头算研究

此文用从头计算法，在ＨＦ、ＭＰ２、ＭＰ３水平下，使用基组６—３１Ｇ、６—３１＋Ｇ对ＳｉＯ的等电子分子ＳｉＸｍ（Ｘ＝Ｂｅ、Ｂ、Ｃ、Ｎ、Ｐ、Ｎｅ，ｍ＝－４～＋２）进行了几何优化，并计算了相应的平衡几何构型下的振动频率，对ＳｉＯ分子，使用ＱＣＩＳＤ（Ｔ）方法考虑了不同水平下的电子相关效应，并考虑了不同基函数６－３１＋Ｇ和６－３１１＋Ｇ的影响。计算结果表明，所有分子的势能曲线都有稳定的极小值，并且键长与频率在ＨＦ、ＭＰ２、ＭＰ３水平上都呈现出明显的规律性，通过与实验上存在的稳定分子ＳｉＯ相比较，可以预言ＮＳＩｉ－和ＳｉＦ＋比其它分子有较明显的成键可能性，所以，ＮＳｉ－和ＳｉＦ＋有可能形成稳定的分子。     

乙胺分子的多光子电主过程质谱研究

报道了乙胺分子在４４０－４７５ｎｍ波长范围内多光子电离（ＭＰＩ）质谱（ＭＳ）研究结果。碎片离子主要由母体离子碎裂模式产生。母体离子ＣＨ３ＣＨ２ＮＨ２由经３ｓ里德堡态的（２＋２）共振多光子电离产生后，大部分发生β键断裂，形成ＣＨ２＝Ｎ＋Ｈ２离离子，还有一部分再吸收一个光子，通过Ｃ－Ｈ（ＣＨ２）键的断裂产生了ＣＨ３ＣＨ－ＮＨ２离子。ＣＨ３ＣＨ＝ＮＨ２和ＣＨ２＝ＮＨ２离子最容易发生的碎裂过程是脱去氢分子     

一甲基硫脲与支持电解质的阴离子在银电极上共吸附的拉曼光谱研究

本文用电化学现场表面增强拉曼散射光谱（ＳＥＲＳ）技术研究了ＭＴＵ在ＨＣｌＯ４、Ｈ２ＳＯ４和ＨＮＯ３介质中分别与一种或两种无机阴离子的共吸附行为，发现ＣｌＯ－４、ＳＯ２－４和ＮＯ－３等弱吸附无机阴离子均能被ＭＴＵ诱导物理吸附在其质子化了的氨基（ＮＨ＋３）上，这三种无机阴离子被ＭＴＵ诱导物理吸附的强弱顺序是：在电极电位位于－０．２Ｖ～－０．７Ｖ区间时，ＳＯ２－４＞ＣｌＯ－４＞ＮＯ－３，在电位位于－０．８Ｖ～－１．２Ｖ区间时，ＣｌＯ－４＞ＳＯ２－４＞ＮＯ－３。     

N2分子X^1Σg^＋,A^3Σu^＋和B^3Пg的势能函数

用文献［１，２，８］介绍的方法推导了Ｎ２分子的基态（Ｘ＾１Σｇ＾＋）的激发态（Ａ＾３Σｕ＾＋和Ｂ＾３Пｇ）的合理离解极限。计算并比较了在６－３１１Ｇ＾＊基集合，ＵＨＦ、ＣＩＤ、ＵＣＩＳＤ和ＱＣＩＳＤ水平下Ｎ２分子上述三个电子态的平衡结构和谐振频率；并用ＱＣＩＳＤ／６－３１１Ｇ＾＊计算了各态的系列单点势能值，由正规方程组拟合Ｍｕｒｒｅｌｌ－Ｓｏｒｂｉｅ函数得到了相应各态的完整势能函数，结果与实验数计     

四—（对—羟基苯基）卟啉在水／三氟乙酸溶液中J—聚集的光谱研究

本文研究了四－（对－羰基苯基）卟啉（ＴＣＰＰ）在Ｈ２Ｏ／ＣＦ３ＣＯＯＨ、Ｈ２Ｏ／ＣＣＩ３ＣＯＨ和Ｈ２Ｏ／ＣＨ３ＣＯＯＨ溶液中的ＵＶ－Ｖｉｓ吸收光谱、荧光光谱和拉曼光谱。实验表明,ＴＣＰＰ在Ｈ２Ｏ／ＣＨ３ＣＯＯＨ和Ｈ２Ｏ／ＣＣＩ３ＣＯＯＨ溶液中以分子态的Ｎ－质子化卟啉Ｈ８ＴＣＰＰ＾２＋存在,而在Ｈ２Ｏ／ＣＦ３ＣＯＯＨ中则形成Ｈ８ＴＣＰＰ＾２＋的Ｊ－聚集体。Ｊ－聚集体显示,ＵＶ－Ｖｉｓ吸收光谱和荧光光     

N_2分子X~1Σ_g~ ,A~3Σ_u~ 和B~3Π_g的势能函数

用文献［１，２，８］介绍的方法推导了Ｎ２分子的基态（Ｘ１Σ＋ｇ）和激发态（Ａ３Σ＋ｕ和Ｂ３Πｇ）的合理离解极限。计算并比较了在６－３１１Ｇ基集合，ＵＨＦ、ＣＩＤ、ＵＣＩＳＤ和ＱＣＩＳＤ水平下Ｎ２分子上述三个电子态的平衡结构和谐振频率；并用ＱＣＩＳＤ／６－３１１Ｇ计算了各态的系列单点势能值，由正规方程组拟合Ｍｕｒｒｅｌ－Ｓｏｒｂｉｅ函数得到了相应各态的完整势能函数，结果与实验数计算值符合得比较好。     

沙蚕磷草酸盐的合成与光谱表征

用１－二甲氨基－２,３－二氯丙烷和Ｏ,Ｏ－二甲基－二硫代磷酸盐反应合成了一种新的有机磷杀虫剂沙蚕磷,还制备了它的草酸盐。用１Ｈ、１３Ｃ核磁共振波谱、红外光谱及质谱法表征了沙蚕磷草酸盐的分子结构,结果表明反应产物是１,３－二取代产物。沙蚕磷的分子结构为（ＣＨ３）２Ｎ＋ＨＣＨ［ＣＨ２ＳＰ（Ｓ）（ＯＣＨ３）２］２Ｃ２Ｏ４Ｈ－［Ｏ,Ｏ,Ｏ′,Ｏ′－四甲基－Ｓ,Ｓ′－（２－Ｎ,Ｎ－二甲氨基丙撑）－双－二硫代磷酸酯草酸盐］。     

角分辨XPS对自组装单分子层厚度和官能团位置的定性及定量研究

用角分辨ＸＰＳ（Ａｎｇｌｅ－ｒｅｓｏｌｖｅｄＸＰＳ）研究研究了ＨＳ（ＣＨ２）１０ＣＯＯＨ（Ｉ）ＨＳ（ＣＨ２）３ＯＣ６Ｈ４Ｎ＝ＮＣ６Ｈ４（ＣＨ２）７ＣＨ３（ＩＩ）和ＨＳ（ＣＨ２）６ＨＳ（Ⅲ）３种分子在Ａｕ膜表面制备的自组装单分子层，得出了（Ｉ）中Ｓ原子，（Ⅱ）中Ｓ，Ｎ原子距膜表面的垂直距离，并结合构象分析确定了分子的取向和倾角，对分子（Ⅲ）则得出分子在紫外光照射下氧化反应的选择性，发现氧化主要在底层     

表面润湿法合成β沸石体系中晶种作用的研究

系统研究了表面润湿法合成β沸石的体系中,干晶种、润湿态晶种、异晶晶种(Y沸石、ZSM 5沸石)以及碱处理β沸石晶种在此晶化体系中的作用.采用β沸石产品及异晶作晶种时,可使产品的相对结晶度稍有提高,但对沸石微晶核的结构导向作用不明显.经浓碱液处理20min后的β沸石产品(碱处理晶种)作晶种引入晶化体系后,可以显著提高产品的相对结晶度,降低模板剂的用量,缩短晶化诱导期,成为表面润湿法合成β沸石体系的有效晶种形式.     

TRAPDOR double-resonance and high-resolution MAS NMR for structural and template studies in zeolite ZSM-5

A combination of ²⁷Al magic-angle spinning (MAS)/multiple-quantum (MQ) MAS, and ²⁷Al–{¹⁴N} TRAnsfer of Population in DOuble-Resonance (TRAPDOR) nuclear magnetic resonance (NMR) was used to study aluminium environments in zeolite ZSM-5. ²⁷Al–{¹⁴N} TRAPDOR experiments, in combination with ¹⁴N NMR were employed to show that the two tetrahedral peaks observed in the ²⁷Al MAS/3Q-MAS spectra of as-synthesized ZSM-5 are due to aluminium atoms occupying crystallographically inequivalent T-sites. A ¹³C–{²⁷Al} TRAPDOR experiment was used to study the template, tetrapropyl ammonium bromide (TPABr), in the three-dimensional pore system of ZSM-5. The inequivalency of the methyl groups of TPA was observed in the ¹³C–{²⁷Al} TRAPDOR spectra of as-synthesized ZSM-5 and the motion of the methyl end of the propyl chain appeared to be more restricted in the sinusoidal channel than in the straight channel.     

Ultrasound-assisted rapid hydrothermal design of efficient nanostructured MFI-Type aluminosilicate catalyst for methanol to propylene reaction

The influence of ultrasound-assisted rapid hydrothermal synthesis of aluminosilicate ZSM-5 catalysts was examined in this work. A series of MFI-type nanostructured materials with sonochemical approach and conventional heating were synthesized and evaluated for conversion of methanol to propylene reaction. The prepared samples were tested by characterization analyses such as XRD, FESEM, BET-BJH, FTIR, TPD-NH₃ and TG/DTG. The obtained results confirmed that ultrasound treatment enhanced the nucleation process and crystal growth for ZSM-5 sample synthesized at moderate temperature of 250 °C. Therefore, it was found the formation of pure MFI zeolite with high crystallinity and improved textural, structural and acidic properties for ZSM-5(UH-250) sample compared with the other zeolites. This observation was attributed to the relationship between the perfect crystallization mechanism and catalytic properties, which led to producing an efficient MFI zeolite toward the optimal catalytic performance. In this manner, the methanol conversion and products selectivity of prepared materials were carried out in MTP reaction at 460 °C and atmospheric pressure. The ZSM-5(UH-250) zeolite with slower deactivation regime exhibited the constant level of methanol conversion (84%) and high propylene selectivity (78%) after 2100 min time on stream. Moreover, the synthesis pathway for MFI zeolite at moderate temperature and also deactivation mechanism of improved sample were proposed.     

CuCoMn-zeolite双功能催化剂转化生物质基合成气制取液态烃

选用四种不同的分子筛(SAPO-34, ZSM-5, Y, MCM-41)与CuCoMn(高醇合成组元)构成双功能催化剂,利用N₂吸脱附、H₂-TPR、XRD、NH₃-TPD等表征了催化剂的结构性质. 研究了催化剂在生物质基合成气一段法制取液态烃燃料的应用. 相比于CuCoMn催化剂,加入分子筛的双功能催化剂均不同程度地提高了液体烃燃料的选择性及收率,且收率按顺序递减呈CCM-ZSM-5>CCM-SAPO-34>CCM-Y>CCM-MCM-41. 同时,共沉淀法制备的CuCoMn-ZSM-5 (20wt%, Si/Al=100) 具有最佳的CO转化率(76%)及液体产物收率(30%). 相比于CuCoMn氧化物,双功能催化剂的比表面及孔容均得到提高. CCM-ZSM-5具有适中的微孔尺寸和中等强度的酸性,增加CCM-ZSM-5中ZSM-5含量或降低ZSM-5中的Si/Al比,均有利于提高酸性位的数量,主要是较弱的酸性位. 而共沉淀法制备的CCM-ZSM-5具有更好的金属分散性及还原性能.     

Equilibrated thermodesorption studies of adsorption of n-hexane and n-heptane on zeolites Y, ZSM-5 and ZSM-11

Gravimetric measurements of thermodesorption of n-hexane and n-heptane were performed under quasi-equilibrium conditions. Differential thermodesorption profiles for ZSM-5 and ZSM-11 showed two peaks, but for Y zeolites, only one thermodesorption peak was observed. A model function, derived from the Langmiur adsorption model, was fitted to the experimental data, and the model parameters (the adsorption entropy and enthalpy) were estimated. The two-step desorption profiles observed for ZSM-5 and ZSM-11 were attributed to the commensurate freezing effect, i.e. a transition in the adsorbed phase resulting in ordering of the adsorbed molecules in the zeolite channels. The results observed for ZSM-11 indicate that the zigzag channels typical for ZSM-5 micropore system are not necessary for this transition to occur.     

Physicochemical characteristics of ZSM-5/SAPO-34 composite catalyst for MTO reaction

SAPO-34 and ZSM-5 are the most well-known catalyst for MTO reaction. A combination of ZSM-5 and SAPO-34 might give rise to optimal catalyst to meet a change of market demand for ethylene, propylene and butadiene. In this study, we have developed ZSM-5/SAPO-34 composite catalysts to control the composition of light olefins in MTO reaction. ZSM-5/SAPO-34 composite catalysts showed very different physicochemical and catalytic properties with respect to ZSM-5 and SAPO-34 synthetic procedure. The physicochemical properties of the composite catalysts have been compared by XRD, SEM, N₂ isotherm, FT-IR and NH₃-TPD. Their catalytic performances were also evaluated for MTO reaction. The series composite catalyst synthesized by successive crystallization of SAPO-34 synthetic gel after ZSM-5 crystallization exhibited relatively high catalytic performance.     

ZSM—5分子筛生成中的模板效应：^13C—NMR对TBA^＋体系的研究

在合成一系列ZSM-5/11分子筛的基础上,用固体高分辨~(13)C-NMR技术考察样品中模板剂TBA~+的存在状态.讨论了TBA~+在ZSM-5和ZSM-11孔道中的分布方式,并发现了TBA~+的分解产物正丁胺的存在,从而说明了在SiO_2/Al_2O_3不十分高的体系中,TBA~+和正丁胺是ZSM-5共生晶相的模板剂。     

一种生物柴油代用品在HZSM-5分子筛催化剂上的催化热解

为了深入了解生物柴油在ZSM-5沸石上的催化反应机理,在常压的流动反应器中进行了生物柴油代用品丁酸甲酯在氢型ZSM-5(HZSM-5)催化剂上的热解和催化热解. 热解产物使用气相色谱-质谱法定性和定量测量. 动力学模型和实验表明,气相中氢提取反应是热解过程中丁酸甲酯分解的主要途径,但在HZSM-5上,丁酸甲酯则主要通过解离生成烯酮和甲醇消耗;与无催化反应相比,丁酸甲酯在HZSM-5上的初始分解温度降低了约300 K. 并且通过Arrhenius方程获得了在催化热解和均相热解条件下丁酸甲酯消耗的表观活化能. 明显降低的表观活化能证实了HZSM-5对丁酸甲酯热解的催化性能. 此外催化剂的活化温度对HZSM-5的某些催化性能具有一定的影响. 该研究对进一步的实际生物柴油燃料的催化燃烧具有一定的指导意义.     

Mn／ZSM-5催化剂及其SCR催化性能研究

采用液态离子交换法制备了不同含量的Mn／ZSM-5型分子筛催化剂,并考察了上述催化剂的物理化学特性及其在NH3-SCR反应中的催化性能。理化分析结果表明：所制备催化剂在Mn含量≤9．2％时具有高度的分散性,分子筛表面团聚的氧化锰颗粒粒径小于4nm;锰元素主要富集于分子筛的浅层及表面。催化性能研究结果表明：Mn含量达到1...