氧化锆层柱鳞酸锆的制备及性能

考察了不同制备因素对形成氧化锆层柱磷酸锆的影响,发现适中的锆离子浓度,较低的反应温度及较长的反应时间有利于形成稳定的氧化锆层柱磷酸锆.样品经250℃焙烧后形成较为规整的层柱结构,氧化锆柱与层板间以P-0-Zr键相连,比表面为107～183m2/g,孔径较集中地为2.5nm.层柱样品表面只存在L酸位,无B酸位.对异丙醇脱水反应和苯甲醛还原反应有较好的反应活性,其比活性优于纯的氧化锆,表明它具有良好的酸催化和酸碱双功能催化作用.     

氧化铬层柱磷酸锆的制备及催化性能

详细研究了有机胺品种、层板预撑态、水解度以及Ｃｒ加入量等制备因对氧化铬层柱磷酸铬结构和性能的影响，用乙胺胶体化法制备的氧化铬层柱磷酸锆比表面积可高达４８２ｍ＾２／ｇ，而孔径集中在２．６ｎｍ附近，层板胶体化时表面磷酸根的知度水有利于提高支柱产品的比表面和形成规整的平板型层间孔，用ＴＧ，ＩＲ，ＸＲＤ和Ｎ２吸附等温线方法研究了氧化铬柱了的形成过程和热稳定性，异丙醇脱水和异丙苯裂解反应结果表明，氧化铬层柱     

混合金属氧化物柱撑α-磷酸锆的研究

制备、表征了混合铝/铬金属氧化物柱撑α-磷酸锆(Al/Cr-ZrP),并对胶体化使用有机胺的种类、柱化液金属离子浓度以及金属离子用量等因素进行了研究。研究表明以乙醇胺为胶体化有机胺比使用正丙胺为胶体化有机胺所得到的产物的层间距更大;采用较低金属离子浓度、较高金属离子用量有利于Al/Cr-ZrP的合成。在Al/Cr比为1、以正丙胺为胶体化有机胺、金属离子浓度为0.067mol·L^-1、金属离子用量为6.67CEC的条件下,制备出了混合金属氧化物柱撑α-磷酸锆,其层间距可达3.60nm,     

α-磷酸锆层柱材料的制备、表征及其催化羰基化性能

采用配体４－ＣＨ３ＳＣ６Ｈ４ＮＨ２插层的α－磷酸锆为插层主体,将Ｒｈ６３＋引入层状材料的层析之间制备了新型层柱催化材料Ｚｒ（ＨＰＯ４）１．７０（ＣＨ３ＳＣ６Ｈ４ＮＨ２）１．０９（ＰＯ４）０．３０Ｒｈ０．１０．５．５２Ｈ２Ｏ,其是距为２．３６变为１．５６ｎｍ,结晶度有所下降。     

大比表面层柱磷酸锡的制备和催化性能

详细研究了氧化铬层柱磷酸锡的制备规律，革新了文献中丙胺在量季铵盐的两步胶体化法，用有机胺使层板一步胶体化成功地制备了高比表面积的层柱磷酸锡，其最高比表面积达４４５ｍ＾２／ｇ。样品经４００℃焙烧后仍具有良好的层柱结构，可形成规整的平行板型中孔，孔径集中在１．７￣５ｎｍ范围内。丙醇脱水和异丙苯裂解反应表明氧化锆层柱磷酸锡具有弱酸催化活性；环己烷脱氢反应表明，氧化铬层柱磷酸锡比负载型氧化铬催化剂有更高的     

大比表面负载氧化铁的氧化硅层柱磷酸锆制备和 催化性能研究

提出了一种以氧化硅层柱磷酸锆(SiO~2-ZrP)的前驱体,氨丙基硅酸酯嵌入磷酸锆(APS-ZrP)为载体制备负载氧化铁的氧化硅层术磷酸锆的新方法。与传统方法相比,新方法制得的样品具有较大的比表面和孔容。X射线粉末衍射(XRD)和程序升温还原(TPR)的结果表明采用新方法有利于氧化铁在载体表面的高度分散,分散阈值为0.25gFe~2O~3/g(SiO~2-ZrP),远超过直接以SiO~2-ZrP为载体浸渍草酸铁铵的传统方法得到样品。同时,用新方法制得的氧化铁催化剂表现了较高的乙苯脱氢活性,是一类值得研究的催化材料。     

苯磺酸修饰的层柱磷酸锆的制备及催化应用

以共缩合方法制备了一系列苯磺酸修饰的层柱磷酸锆材料,利用N2吸附、Si核磁共振、红外光谱和热重分析等方法对其结构进行了表征. 将其应用于对苯二酚与叔丁醇烷基化反应中,结果发现催化剂合成时的投料比对其催化性能有较大的影响,催化剂ZrP-0.4-2-10%-PhSO3H的催化性能最佳,反应4 h对苯二酚的转化率为85.4%,2-叔丁基对苯二酚得率达到58.5%. 酸性表征结果显示,催化剂活性与其表面可接触酸性位的数目密切有关. 该催化剂还具有较好的重复利用性能,反应3次后产物得率仅下降10%. 催化剂失活是由于磺酸基团的脱落或活性位被积碳覆盖所引起.     

磷酸锆类层柱催化剂的制备、表征及其催化甲醇氧化羰基化反应性能

以层状α－磷酸锆为插层主体,采用高温固相离子交换插层法制备Ｃｕ＾２＋,Ｋ柱撑的磷酸锆类层柱催化剂,并用ＸＲＤ,ＩＲ和ＴＧ等方法对其进行了表征。结果表明,金属离子柱撑的α－磷酸锆类层柱催化剂的层间距由原来的０．７６ｎｍ扩撑至０．８１ｎｍ,结晶度有所下降。     

4—CH3SC6H4NH2对α—磷酸锆的插层特性

制备了４－ＣＨ３ＳＣ６Ｈ４ＮＨ２（ＭＭＡ）插层的α－Ｚｒ９ＨＰＯ４）２．Ｈ２Ｏ，研究了不同实验条件下ＭＭＡ的插层特性，发现插层反应与ＭＭＡ和α－ＺｒＰ摩尔比Ｒ有关；（１）当Ｒ〉２时，有插层产物相产生，但是即使在ＭＭＡ大大过量的条件下，仍然有部分α－ＺｒＰ颗粒大小等有关；插层产物的层间距约为２．３６ｎｍ，，层间距的大小不随反应物浓度，温度等条件变化。     

Zr(SO4)2·4H2O的层状结构、插层及催化性能

利用ＸＲＤ，ＴＰＤＥ，ＰＥＤ和ＴＧ－ＤＴＡ等为主要研究手段，深入分析了Ｚｒ（ＳＯ４）２·４Ｈ２Ｏ的层状结构特性和插层性能，并以乙酸与乙二醇单醚的酯化反应普目标反应考察了其催化性能。研究结果表明：Ｚｒ（ＳＯ４）２·４Ｈ２Ｏ是一种具有中等强度酸性的层状化合物，位于层间的结晶水是产生Ｂ酸中心的来源；有机胺类分子具有较强的插层能力，胺的插入可将层板撑开并使层间距增大，从而进一步证实存在层间结晶水所产生的Ｂ     

S~2O~8^2^-处理的ZrO~2固体超强酸上的正丁烷异构化反应

首次报道了由浸渍过硫酸根的方式制备固体超强酸。讨论了焙烧温度、浸渍浓度以及ZrO~2前驱体沉淀条件对样品性质的影响,并研究了它们对正丁烷异构化反应性能。实验结果表明,600-650℃焙烧、0.25-0.50mol/LS~2O~8^2^-浸渍反加沉淀的ZrO~2具有最高超强酸性。与相同条件下制备的SO~4^2^-/ZrO~2相比,S~2O~8^2^-/ZrO~2上正丁烷250℃异构化活性是SO~4^2^-/ZrO~2的2倍,可能是由于它具有较多的中强酸位并具有与SO~4^2^-/ZrO~2不同的活性位结构。     

载钯磷酸锆的制备和催化性能研究

本文制备了载钯磷酸锆，作为由丙酮和氢气一步法合成甲基异丁基甲酮（ＭＩＢＫ）的催化剂．考察了制备时的ｐＨ对催化剂比表面积、酸度、酸强度以及催化性能的影响．     

Synthesis and structure of a new zirconium phosphate with double-stranded chains

The zirconium phosphate [Zr(HPO₄)(PO₄)F₂] · 1.5H₂en was prepared, and its structure was determined by X-ray diffraction analysis.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1897–1901, November, 1994.The work was carried out with financial support from SERC (UK) and the National Foundation of Natural Sciences (China).     

Catalytic activity and acidity of Al pillared clays and zeolites in different hydrocarbon reactions

In comparison with zeolites, a variety of Al pillared clays did not prove as promising cracking catalysts, possibly because their Br?nsted sites are hidden. In the less demanding double bond shift isomerization, both catalyst types were comparable probably due to the presence of Lewis sites on both catalysts.     

Selective oxidation of alcohols over copper zirconium phosphate

The catalytic activity of copper zirconium phosphate (ZPCu) in the selective oxidation of alcohols to their corresponding ketones or aldehydes, using H₂O₂ as an oxidizing agent, was studied. The oxidation reaction was performed without any organic solvent, phase-transfer catalyst, or additive. Steric factors associated with the substrates influenced the reaction. The catalyst was characterized using X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. It was shown that the interlayer distance increased from 0.74 to 0.80 nm and the crystallinity was reduced after Cu²⁺ intercalation into the layers. This catalyst can be recovered and reused three times without significant loss of activity and selectivity.     

Preparation and characterization of manganese- and samarium-manganese-alumina pillared montmorillonites

A Na-montmorillonite was intercalated with manganese- and samarium-manganese-aluminium solutions. The pillared montmorillonites were characterized by X-ray diffraction and nitrogen adsorption. The presence of manganese and samarium-manganese citrates in the intercalation process modify the distance between the clay sheets and the microporous structure of the pillared montmorillonites.     

Selective oxidation of alcohols over nickel zirconium phosphate

Nickel zirconium phosphate nanoparticles were found to function as efficient catalysts for the selec-tive oxidation of a wide range of alcohols to their corresponding ketones and aldehydes using H2O2 as an oxidizing agent and without any organic solvents, phase transfer catalysts, or additives. The steric and electronic properties of various substrates had significant influence on the reaction con-ditions required to achieve acetylation. The results showed that this method can be applied for the chemoselective oxidation of benzyl alcohols in the presence of aliphatic alcohols. The catalyst used in the current study was characterized by ICP-OES, XRD, NH3-TPD, Py-FTIR, N2 adsorp-tion-desorption, SEM and TEM. These analyses revealed that the interlayer distance in the catalyst increased from 0.75 to 0.98 nm when Ni2+ was intercalated between the layers, whereas the crystal-linity of the material was reduced. The nanocatalyst could also be recovered and reused at least seven times without any discernible decrease in its catalytic activity. This new method for the oxi-dation of alcohols has several key advantages, including mild and environmentally friendly reaction conditions, short reaction time, excellent yields and a facile work-up.     

Calorimetric study of sodium-rich zirconium phosphate

The heat capacity investigation of crystalline pentasodium zirconium tris(phosphate) was carried out in a vacuum adiabatic calorimeter between 7 and 340 K and in a differential scanning calorimeter of the heat bridge type between 330 and 620 K. Between 389 and 424 K, an isostructural solid-to-solid phase transition of Na₅Zr(PO₄)₃, has been found, the nature of which is connected with a centering of off-centered zirconium atoms in octahedral sites and an occupation transfer between sodium sites in the structure. The results were used to calculate the characteristics of the phase transition and the thermodynamic functions of Na₅Zr(PO₄)₃: the transition temperature T°_trs, enthalpy of transition Δ_trsH°, entropy of transition Δ_trsS°; enthalpy H°(T)−H°(0), entropy S°(T) and Gibbs function G°(T)−H°(0) over the range from 0 to 620 K. From hydrofluoric acid solution microcalorimetry, the enthalpy of solution of Na₅Zr(PO₄)₃ at 298.15 K has been determined and the standard enthalpy of formation has been derived. By combining the data obtained by the two techniques, the Gibbs function of formation of Na₅Zr(PO₄)₃ at 298.15 K has been calculated.     

丝光沸石负载SO~4^2^-/ZrO~2超强酸的研究

制备了一系列丝光沸石(HM)负载SO~4^2^-/ZrO~2(SZ)超强酸催化剂,并研究了它们比表面、孔容、硫含量及超强酸性的变化规律。结果发现,HM在负载SZ后超强酸性显著提高,可以在35℃条件下催化正丁烷异构化反应。吡啶吸附红外结果表明,适量负载SZ可增加HM的Lewis酸量和总酸量,从而使甲苯岐化和邻二甲苯异构化反应等酸催化反应活性显著提高。XRD结果证实,在HM上负载适量SZ不会破坏HM的结构,但负载量过大(>60%,质量分数)则会引起沸石结构的塌毁。     

SO_4~(2-)/ZrO_2-TiO_2固体超强酸的制备

用低温陈化和添加稀土添加剂 (硝酸镧 )的方法制备了 SO2 - 4/Zr O2 -Ti O2 固体超强酸 ,用 IR和 XRD对样品进行了表征 .并通过在 3 5℃条件下催化正丁烷异构化反应和流动指示剂法考察了 Zr和 Ti的摩尔比以及稀土添加剂对样品的酸性和催化活性的影响 . IR和 XRD谱图显示 ,该条件下制备的样品具有较多的超强酸位 ,其晶体为 Ti O2 的锐钛矿晶相结构