钛硅分子筛ETS-10的合成和表征

以硅酸钠溶胶、硫酸钛为起始原料,在含KF碱性水热体系中制备出ETS-10钛硅酸盐分子筛;考察了原料的配比、晶化时间与温度对ETS-10合成的影响。应用XRD、SEM、EDX、FTIR和N2吸附技术表征了合成的ETS-10的结构和物性。结果表明,用组成为n(SiO2)∶n(TiO2)∶n(Na2O)∶n(KF)∶n(H2O)=7.5∶1.0∶5.0∶3.0∶198的凝胶,在463K(48h)和无模板剂的条件下,合成出结晶度良好的ETS-10。ETS-10晶体具有规则的四方切角锥形晶貌和微孔性质,比表面积和孔容分别为383.75cm2/g和0.16cm3/g;典型样品的化学组成接近已知的ETS-10组成表达式(Na,K)2TiSi5O13.4H2O。     

高结晶度ETS-10分子筛的合成与表征

采用水热合成法成功合成出高结晶度ETS-10分子筛。通过XRD、N2吸附-脱附、FTIR、SEM和NMR等方法对样品进行了表征,并考察了不同合成条件对ETS-10分子筛结晶度的影响。结果表明,碱度、硅钛比、晶化时间对分子筛结晶度影响显著。在分子筛制备过程中,钛溶解分散于凝胶体系,并在晶化过程中完全进入分子筛形成Si-O-Ti骨架结构,是合成高结晶度ETS-10分子筛的关键。制备的ETS-10分子筛晶粒形状规整,比表面积高,无杂晶相,具有高的结晶度。     

5,10,15,20-四(4-羟基苯基)卟啉的合成及光谱性质的研究

以吡咯、对甲氧基苯甲醛和吡啶盐酸盐为原料,采用两步法合成了5,10,15,20-四(4-羟基苯基)卟啉(THPP),反应总收率39.2%,产品纯度大于97%;采用微波加热法提高了该产物的合成效率;用1HNMR、HPLC-MS和HRMS对化合物进行了结构和纯度表征;研究了其在不同溶剂和不同pH值条件下的光谱性质.     

4-硝基-4'(10-溴癸烷氧基)对苯席夫碱的合成及表征

合成了席夫碱型离子液晶重要中间体——标题化合物。以对氨基苯酚和对硝基苯甲醛为反应单体,合成4-硝基-4'-羟基对苯席夫碱;将其与1,10-二溴癸烷反应,合成标题化合物。采用IR、UV、Raman、1HNMR、MS等手段对化合物进行结构表征。     

亚微米4A分子筛的合成与表征

以云南云天化国际股份有限公司的磷肥副产物硅胶湿样为基础原料,补加铝酸钙,水热法制备亚微米4A分子筛.采用XRD、SEM和FT-IR等分析手段对产品进行了表征.结果表明采用水热法制备的产品结晶度为95%,形状规则、大小均匀,分布范围较窄;粒度较小、粒度≤1μm的可达到100%;钙离子交换容量为336 mgCaCO3/g(干基)4A分子筛,白度为95%,完全满足洗涤助剂的要求.     

Synthesis and characterization of tantalum silicalite molecular sieves with MFI structure

Tantalum silicalite-1 (TaS-1) with MFI structure was prepared using the hydrothermal synthesis method. X-ray diffraction, scanning and transmission electron microscopies, Fourier transform infrared spectroscopy, ultraviolet–visible (UV–vis) diffuse reflectance spectroscopy, ²⁹Si magic-angle spinning nuclear magnetic resonance spectroscopy, temperature-programmed desorption of ammonia (NH₃-TPD), physical adsorption of nitrogen and elemental analysis were then performed to evaluate its physico-chemical properties and provided evidence for the incorporation of Ta⁵⁺ into the zeolite framework. The unit cell volume of tantalum silicalite-1 increased linearly with increasing tantalum content, suggesting isomorphous substitution of Si⁴⁺ by Ta⁵⁺ in the lattice framework. The characteristic framework infrared spectra shifted to lower frequencies as Ta⁵⁺ was incorporated into the silicalite lattice and showed a characteristic absorption band at 965 cm⁻¹, probably due to Si---O---Ta linkages. In the UV–vis spectrum, the absorption assigned to the presence of Ta⁵⁺ in the zeolite framework was observed at around 200 nm. In addition, NH₃-TPD studies revealed weak acidity in tantalum silicalite-1 due possibly to [Ta(OH)---Si] sites in the framework.     

乙烯基吡啶-偏二氯乙烯共聚物的合成与表征

以过氧化二苯甲酰（BPO）为引发剂,以羟乙基纤维素（HEC）为分散剂,采用悬浮聚合方法合成了乙烯基吡啶-偏二氯乙烯共聚物,然后采用特性粘数、UV、FT-IR、1H-NMR、DSC、TG等测试手段研究了乙烯基吡啶-偏二氯乙烯共聚物的结构和性能。     

聚4-乙烯基吡啶的合成与表征

以过氧化二苯甲酰(BPO)为引发剂,用悬浮聚合的方法制备了较高相对分子质量的聚4 乙烯基吡啶(P4VP)。通过对聚合产物相对分子质量测试结果的分析,研究了单体与水的体积比、引发剂用量、分散剂用量、反应时间、反应温度、搅拌速度等因素对4 VP聚合反应的影响。结果表明,聚合时间为1h、聚合温度为60℃、引发剂的质量分数(占单体量)为0.8%左右、分散剂的质量分数(占单体量)为0.6%、搅拌速度为300r/min时,P4VP的重均分子量就能达到6×105～9×105。另外,采用紫外吸收光谱(UV)、红外吸收光谱(IR)、核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)、热重 差热分析(TG DTA)等测试手段研究了P4VP的结构和性能。     

Effect of the incorporation of ETS-10 into alumina on metal-support interactions and hydrodesulfurization activity

Effect of the incorporation of ETS-10 into alumina on metal-support interactions was firstly studied systematically by the techniques of DSC, TG, XRD, DRS and LRS. The results show that the introduction of ETS-10 substantially improves metal-support interactions, inhibits the formation of inactive aluminium tungstate species and nickel spinel, and stimulates more polymeric tungsten species formation, which facilitates the promoting effect of nickel on tungsten and contributes to a noticeable increase in HDS activity.     

Na4Ca3(AlO2)10的合成和浸出行为

以分析纯CaCO3,Al2O3和Na2CO3为原料,在1100~1250℃合成了Na4Ca3(AlO2)10,研究了浸出时间、浸出温度、液固比及溶液中碳酸钠和氢氧化钠浓度对Na4Ca3(AlO2)10浸出性能的影响. 结果表明,在1200℃烧结30 min,可以合成纯度高于90%的Na4Ca3(AlO2)10. 当碳酸钠浓度为80 g/L、氢氧化钠浓度18 g/L时,Na4Ca3(AlO2)10在40℃浸出10 min的氧化铝浸出率达到90%以上. 当碳酸钠浓度降为30 g/L时,Na4Ca3(AlO2)10在60℃浸出15 min的氧化铝浸出率大于85%. 浸出时添加氢氧化钠有利于氧化铝浸出率的提高,氢氧化钠浓度大于5 g/L时,氧化铝浸出率可提高10%以上. Na4Ca3(AlO2)10的浸出性能优于12CaO·Al2O3和CaO·Al2O3.     

CuO x Sitting on Titanium Silicate (ETS-10): Influence of Copper Loading on Dispersion and Redox Properties in Relation to de-NO x Activity

A series of copper-based catalysts prepared by dispersing the CuO phase on a titanium silicate (ETS-10) crystalline matrix were studied towards their de-NO_x activity. The copper concentration ranged from 0.7 to 70 atom_Cu nm^-2, corresponding to 3-18 wt%. The activity of NO reduction with ethylene was related to morphological and chemical properties of the catalysts. The crystalline character of the catalysts possessing high internal surface and microporosity was preserved up to ca. 3 atom_Cu nm^-2. At higher copper concentration, structure collapse was observed with formation of large aggregates of CuO_x. Temperature-programmed reduction experiments showed two reduction peaks with maximum temperatures at ca. 470 and 560 K, for catalysts with copper concentration up to 3.5 atom_Cu nm^-2. The two peaks corresponded to the reduction of highly dispersed and non-interacting CuO_x species (470 K) and of crystalline CuO_x species (560 K). Catalysts containing copper at higher concentration had only the high-temperature reduction peak, indicating the presence of large aggregates of CuO_x. All the results collected seem basically consistent with a value of about 2.5-3 atom_Cu nm^-2 for the maximum dispersion capacity of CuO on the ETS-10 matrix. The amount of copper deposited on ETS-10 affects the activity of catalysts towards NO reduction. The turnover frequencies per copper site calculated as a function of copper concentration showed a clear decreasing trend starting from 0.7 to 3.5 atom_Cu nm^-2. Catalysts with higher copper concentration were completely inactive towards NO reduction.     

Synthesis and Characterization of ETS-10/Chitosan Nanocomposite Membranes for Pervaporation

Chitosan (CS) and microporous titanosilicate ETS-10/CS mixed matrix membranes (MMMs) were prepared. The pervaporation performance was tested on the water-ethanol mixtures in the range 85–96 wt.% ethanol. The permeate flux increased from 0.45 to 0.55 kg m^?2 h^?1 at 50°C for the ETS-10/CS MMM with respect to the pure CS membranes. Characterization by SEM and TEM, XRD, DSC, and TGA allowed inferring an intimate contact between the dispersed ETS-10 and the continuous chitosan phase. The 5 wt.% loading of titanosilicate scarcely decreased the hydrophilic character of the mixed matrix membrane but increased the molecular sieving effect on the transport and separation properties, thus affecting the membrane behavior on pervaporation.     

Controlled detitanation of ETS-10 materials through the post-synthetic treatment and their applications to the liquid-phase epoxidation of alkenes

Treatments of ETS-10 titanosilicates with HCl, NH₄Cl or citric acid led to the change in the coordination environment of Ti. These treatments also led to the partial extraction of Ti from the framework of ETS-10. The local structural changes brought about the formation of the active sites for the epoxidation of cyclohexene with H₂O₂. The highest epoxidation activity and efficiency of H₂O₂ as an oxidant were achieved when the original [Na, K]-type ETS-10 was treated with 3.7 mol dm⁻³ NH₄Cl solution followed by the calcination at 723 K.     

Hydrothermal synthesis and characterization of Fe(III)-substituted mordenites

Fe-substituted mordenites were synthesized hydrothermally, partially substituting iron atoms for the framework aluminum of mordenite. XRD, SEM, IR, UV-VIS DRS, ESR, XAS, and catalytic activity studies provided the evidence of Fe³⁺ present in the zeolite framework. The framework IR bands were shifted to lower frequencies as Fe³⁺ ions incorporated into the lattice, and a new Si-O-Fe bond vibration was located near 668 cm^?1. The presence of a signal at g=4.3 in the ESR spectra was assigned to Fe³⁺ isomorphously substituted in the tetrahedral position. EXAFS at the Fe K-edge revealed that the Fe³⁺ ions were present in the zeolite framework in a four-fold coordination with an average Fe-O distance of 1.86 Å. In the UV-vis spectra, an absorption was observed at 375.7 nm which was assigned to the presence of Fe³⁺ in the zeolite framework. A toluene alkylation study reflected that the acidity strength of mordenite is weakened due to the presence of lattice iron species.     

Hydrodesulfurization and hydrodearomatization activities of catalyst containing ETS-10 and AlPO4-5 on Daqing FCC diesel

A Ni–W loaded ETS-10/AlPO₄-5/Al₂O₃ composite support catalyst was optimized and used in hydrodesulfurization (HDS) and hydrodearomatization (HDA) of Daqing FCC diesel feedstock. The result indicated that ETS-10 and AlPO₄-5 showed positive synergism effect. The effects of operating conditions on its catalytic performance were investigated by using a 100 mL hydrotreating test unit. The catalyst showed a remarkable HDS conversion of 99.9% and a HDA conversion of 73.2%. A clean diesel product with ultra-low sulfur content (<1.0 μg/g) and very low polycyclic aromatic content (<2.0 wt.%) was obtained.     

Cadmium(II) removal from aqueous solution using microporous titanosilicate ETS-10

In this work, the removal of Cd²⁺ ions from aqueous solution using microporous titanosilicate ETS-10 was investigated in order to assess its potential as decontaminating agent in tertiary treatments. Accordingly, batch stirred tank experiments were carried out to study the ion exchange kinetics and equilibrium. Results show that pH affects considerably the ion exchange capability of ETS-10: at pH 4 it is 1.567 × 10² eq m⁻³, at pH 6 it is 3.629 × 10³, and no further increment was observed at pH 8. This is an extremely important observation since pH of industrial effluents and other wastewaters rounds 6. Both Langmuir and Langmuir–Freundlich isotherms were fitted to the experimental data measured. The second model performs slightly better as the calculated absolute average deviations show: AAD_L = 2.94% and AAD_LF = 2.40%. Concerning the kinetic behavior, the ion exchange was successfully represented by a Nernst–Planck based model (AAD = 11.9%).     

对溴甲基苯甲酸甲酯的合成研究

在四氯化碳溶液中,在光照条件下对甲基苯甲酸甲酯与N-溴代丁二酰亚胺(NBS)反应合成对溴甲基苯甲酸甲酯。通过正交实验得到对溴甲基苯甲酸甲酯的最佳合成条件为:NBS用量为对甲基苯甲酸甲酯的1.1倍,反应时间为4 h,过氧化苯甲酰为NBS的0.03倍,四氯化碳为对甲基苯甲酸甲酯的11倍,产率90.5%。     

4-(4-氯苯基)环己醇及4-(4-氯苯基)环己酮的合成研究

以氯苯、环己烯、乙酰氯为原料,通过Friedel-Crafts反应、Baeyer-Villiger反应、水解反应得到4-(4-氯苯基)环己醇。通过正交试验得到Friedel-Crafts反应和Baeyer-Villiger反应优化后的工艺条件。4-(4-氯苯基)环己醇总收率达12.9%,较文献收率提高了6%以上。所得醇经次氯酸钠氧化,得到4-(4-氯苯基)环己酮,氧化收率87%,产品的结构经1HNMR、GC-MS鉴定。     

双(4-(对氟苯甲酰基)苯基)苯基氧化膦的合成与表征

以双(4-羧苯基)苯基氧化膦、氟苯等为原料,合成了标题化合物,并采用差示扫描量热法、红外光谱和核磁共振等对产品的结构进行了表征。     

Synthesis and characterization of poly(ethylene terephthalate) nanocomposites with organoclay

Poly(ethylene terephthalate) (PET)/montmorillonite (MMT) nanocomposites were prepared by solution intercalation method. The clay was organo‐modified with the intercalation agent cetylpyridinium chloride (CPC). Wide‐angle X‐ray diffraction (XRD) showed that the layers of MMT were intercalated by CPC. Four nanocomposites with organoclay contents of 1, 5, 10, and 15 wt % were prepared by solution blending. XRD showed that the interlayer spacing of organoclay in the nanocomposites depends on the amount of organoclay present. According to the results of differential scanning calorimetry (DSC) analysis, clay behaves as a nucleating agent and enhances the crystallization rate of PET. The maximum enhancement of crystallization rate for the nanocomposites was observed in those containing about 10 wt % organoclay within the studied range of 1–15 wt %. From thermogravimetric analysis (TGA), we found that the thermal stability of the nanocomposites was enhanced by the addition of 1–15 wt % organoclay. These nanocomposites showed high levels of dispersion without agglomeration of particles at low organoclay content (5 wt %). An agglomerated structure did form in the PET matrix at 15 wt % organoclay. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 140–145, 2004