（K,Na）ZSM—5的酸碱性质及催化性能

采用红外光谱、程序升温脱附、原子吸收光谱、等离子光谱、Hammett指示剂非水滴定和催化活性测试等方法研究了经不同浓度的KOH溶液交换得到的(K,Na)ZSM-5的酸碱性质。结果表明,(K,Na)ZSM-5具有中等强度的L酸位(K~+,Na~+)及弱碱位(AlO_4~-或骨架O~(2-))和强碱位(OH~-).KOH浓度增大.酸性减弱,碱性增强.所得(K,Na)ZSM-5具有较高的异丙醇脱氢、脱水活性.催化性能与酸碱性密切相关.     

Study of the acid-base properties of SiO2-supported NiMoO4 catalysts by temperature-programmed desorption: effect of the support

The acid-base properties of several NiMoO₄ catalysts supported on two silicas and prepared by different methods have been studied by temperature-programmed desorption of NH₃. The catalytic behavior in the oxidative dehydrogenation of isobutane for two NiMoO₄ catalysts with different acid-base properties are compared.     

Spectroscopic methods as instruments for the prediction of catalytic behavior of metal-organic frameworks

The results of the studies of the acid-base and catalytic properties of metal-organic frameworks (MOFs) are generalized. Significant attention is given to possibilities of spectral methods (IR and ESR) for the study of the nature of acid-base sites and determination of the character of their interaction with organic molecules. The influence has been analyzed of the nature of these sites and structural factors on the catalytic properties of MOFs in reactions of the acid-base type. The presented results demonstrate the possibility of using spectroscopic data for the understanding of the nature and specificity of the catalytic effect of MOFs at the atomic molecular level and for the prediction of their catalytic properties.     

Factors determining the catalytic properties of active carbons in some acid-base and redox reactions

The results of the authors’ investigation of the catalytic properties of active carbons in acid-base and redox reactions are summarized. The general principles of controlling the activity of carbon catalysts are described, the main factors in the catalytic processes occurring on these catalysts are revealed, and new ways of using the catalytic properties of carbon sorbents from various sources are considered. The article was translated by the authors. Published in Russian in Kinetika i Kataliz, 2007, Vol. 48, No. 4, pp. 643–648.     

Metal-Support Interaction Which Controls the Oxidation State, Structure and Catalysis of Pd

A metal-support interaction between Pd and various kinds of zeolite and metal oxide supports was studied, which were active in the catalytic combustion and selective reduction of NO. The acid-base properties of supports affected the oxidation state, structure and catalytic activity of Pd. The acid sites of zeolite played the role to anchor the dispersed PdO as evidenced by the dynamic structural change of Pd. It was found that the metal-support interaction is an important factor, affecting the oxidation state, structure and catalytic performance of Pd.     

不同方法合成的沸石咪唑酯骨架结构材料(ZIF-8)的表征和催化性能

以二甲基咪唑为有机连接体和以Zn(OH)₂或Zn(NO₃)₂·6H₂O为Zn源,在甲醇与氨水的混合溶液、甲醇和DMF₃种不同的合成体系中合成了沸石咪唑酯骨架结构材料ZIF-8(分别记为ZIF-8(NH₄OH)、ZIF-8(MeOH)和ZIF-8(DMF),并采用XRD、FTIR、N₂吸附、SEM、TPD及Knoevenagel缩合反应等手段对所合成材料进行了表征。结果表明,采用这3种不同的合成方法均可成功制备出ZIF-8,所合成的ZIF-8的形貌基本一致,但其晶粒大小和酸碱性能有较大区别,同ZIF-8(NH₄OH)和ZIF-8(DMF)相比,ZIF-8(MeOH)晶粒分布集中、平均粒径较小且具有较大的外比表面积和较多的酸碱位。不同方法合成的ZIF-8在苯甲醛和丙二腈的Knoevenagel缩合反应中的催化性能有很大差异,ZIF-8(MeOH)催化活性明显高于ZIF-8(DMF)和ZIF-8(NH₄OH),其较高的催化活性,同其较大的外比表面积和酸碱性能密切相关。     

不同方法合成的沸石咪唑酯骨架结构材料(ZIF-8)的表征和催化性能

以二甲基咪唑为有机连接体和以Zn(OH)2或Zn(NO3)2·6H2O为Zn源,在甲醇与氨水的混合溶液、甲醇和DMF 3种不同的合成体系中合成了沸石咪唑酯骨架结构材料ZIF-8(分别记为ZIF-8(NH4OH)、ZIF-8(MeOH)和ZIF-8(DMF),并采用XRD、FTIR、N2吸附、SEM、TPD及Knoevenagel缩合反应等手段对所合成材料进行了表征。结果表明,采用这3种不同的合成方法均可成功制备出ZIF-8,所合成的ZIF-8的形貌基本一致,但其晶粒大小和酸碱性能有较大区别,同ZIF-8(NH4OH)和ZIF-8(DMF)相比,ZIF-8(MeOH)晶粒分布集中、平均粒径较小且具有较大的外比表面积和较多的酸碱位。不同方法合成的ZIF-8在苯甲醛和丙二腈的Knoevenagel缩合反应中的催化性能有很大差异,ZIF-8(MeOH)催化活性明显高于ZIF-8(DMF)和ZIF-8(NH4OH),其较高的催化活性,同其较大的外比表面积和酸碱性能密切相关。     

Study of acid-modified aluminum oxides produced by centrifugal thermal activation in dehydration of ethanol

Possibility of using products formed in centrifugal thermal activation of hydrargillite to obtain alumina catalysts washed to remove admixtures of alkali metals was considered. A comparison of the physicochemical and catalytic properties of the samples demonstrated that washing with water is more favorable than that with nitric acid; the catalytic activity and acid-base properties of the catalyst surface are determined not only by the content of Na, but also by the whole set of catalyst preparation conditions. The most active of the samples obtained in the study has acidity close to that of industrial aluminum oxide produced by the reprecipitation method, but surpasses it in activity: at 370°C, the total yield of ethylene and diethyl ether reaches a value of 88.8 mol %, which is 4% higher than that for the reference sample.     

载镍ZSM-5沸石中钠的作用

本文通过对一组不同Na含量NiZSM-5沸石的酸性、吸附性及催化活性的测试表明于载镍ZSM-5体系中添加碱金属钠离子, 不仅调节沸石的碱酸功能, 而且增加甲苯的吸附性, 提高甲苯的转化率, 表现出助催化效应。     

Structural organization of phosphorus titanate oxides prepared by the alkoxo method and their catalytic activity in ethylene glycol oxyethylation

The relationship of the structural organization and acid-base properties of the surface of phosphorus titanate oxides prepared from tetra-n-butoxytitanium and phosphorous esters with the catalytic activity and selectivity of these materials in ethylene glycol oxyethylation was studied. Single-phase phosphorus-containing oxides synthesized from 2-diethylamido-4-methyl-1,3,2-dioxophosphorinane and diphenyl(methano)phosphocane have strong surface aprotic acid sites and exhibit high catalytic activity with respect to oxyethylation and a record-breaking selectivity in the formation of the lower homolog, diethylene glycol. The last-mentioned fact is a consequence of the sieve effect exerted by the homogeneous porous structure of supermicropores (8—10 ) of the oxides. An increase in the concentration of the strong acid sites (130 kJ mol^–1) on the oxide surface enhances the catalytic activity. On the basis of the temperature programmed desorption of ammonia and CO₂ and kinetic measurements, a concerted acid-base mechanism was proposed for the catalytic addition of ethylene oxide to ethylene glycol on the phosphorus-titanate surface.     

Acidity and Catalytic Activity of Sulfate Modified Mixed Oxides of Tin and Praseodymium

A comparitive study of the acid-base properties and physico-chemical characteristics of pure SnO₂, sulfated SnO₂ and sulfated binary oxides of Sn and Pr was done. The data were correlated with the catalytic activity of the oxides towards benzoylation of toluene.     

催化剂酸碱性对异丙醇脱水活性的影响

研究了具有不同酸碱中心的催化剂对异丙醇脱水反应活性及选择性的影响,结果表明:催化剂表面有合适的酸碱强度和H_0,max值,能引起高的脱水活性和选择性。红外吸附态证实:在接近反应状态下,催化剂表面出现了-CH₂结构吸附,这表明反应物的碱基(OH基)与催化剂表面酸中心作用的同时,酸基(反应物的β-H)与催化剂表面碱作用,催化剂上这种酸碱活性中心协同作用结果使异丙醇脱水生成丙烯的过程很可能以协同机理方式进行。     

Catalytic properties of oxides in vapor phase oxidation of acetone

The temperature dependences of the rate of oxidation of acetone vapors by oxygen on oxide surface catalysts: V₂O₅, Co₃O₄., MoO₃ and TiO₂ (rutile), and the industrial catalyst VKSh were determined. A series of the catalytic activity of the above surface catalysts was established. The relationship between the catalytic properties of the oxides in the oxidation of acetone and their redox and acid-base characteristics was analyzed. The catalytic activity of the oxides in the oxidation reaction of acetone and methanol were compared.Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 24, No. 1, pp. 114–117, January–February, 1988.     

Effect of acid-base properties on copper catalysts for hydrogenation of carbon dioxide

Acidic or basic components as co-catalysts were added to the Cu-based catalysts for hydrogenation of CO₂. Effects of acid-base properties on the catalytic activity and methanol selectivity are discussed.     

Acid-Base properties of MgCuAl mixed oxides

MgCuAl layered double hydroxides (LDHs) with a hydrotalcite like structure containing different proportions of Mg²⁺ and Cu²⁺ cations have been prepared. Thermogravimetry and X-ray diffraction data indicated that the transformation of LDH into mixed oxides is effective after calcination at 723 K, irrespective of the composition. The acid-base properties of these mixed oxides have been investigated using adsorption microcalorimetry and X-ray photoelectron spectroscopy with NH₃ (for acidity) and SO₂ (for basicity) as probe molecules. Their catalytic behaviour for the conversion of cyclohexanol has been tested. The acid-base properties and the selectivity of catalysts has been related to their composition. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis of layered double hydroxides and their reactivities in 1-butene isomerization after calcination

Layered double hydroxides were synthesized and their catalytic activities tested in 1-butene isomerization after calcination at 723 K. The heat treatment destroyed the hydrotalcite-like structure creating mixed oxides with wide-ranging acid-base properties as revealed by temperature-programmed desorption of carbon dioxide and the double bond isomerization of 1-butene.     

Alkylation of Isobutane with Butenes on Zirconium Sulfate Catalysts

Sulfated zirconia catalysts supported on silica gel and aluminum oxide were prepared by impregnation, and their structure and acid-base and catalytic properties were studied. The parameters of synthesis and characteristics of this catalyst, which ensure high activity and selectivity in liquid-phase alkylation of isobutane with butenes, were determined.     

沸石的表面酸、碱性与甲醇、甲苯侧链烷基化反应

以TPD和质谱检测的TPSR、IR及微型反应器等手段探讨了X型沸石的表面酸、碱性质对甲醇、甲苯侧链烷基化反应的作用及可能的反应历程。     

Main factors determining the catalytic properties of active carbons

The results of the authors' investigations into the catalytic properties of active carbons in acid-base and oxidation-reduction reactions, mostly obtained in recent years, are summarized. On the basis of previous and recent data the main factors affecting the course of the catalytic processes are identified, the general principles governing control of the catalytic activity of carbon catalysts are described, and new ways of using the catalytic properties of carbon sorbents from various sources are established.Institute of Sorption and Problems of Endoecology, Academy of Sciences of Ukraine, Kiev. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 6, pp. 336–344, November–December, 1996. Original article submitted March 22, 1996.     

氮杂穴状大环钴(Ⅱ)配合物的合成、晶体结构及其催化性能

以一个氮杂穴状大环配体为自由配体,与硝酸钴经配合反应合成了一个新的穴状单核钴配合物[CoL(NO_3)]·(NO_3)·8H_2O(1),其晶体结构经X-射线单晶衍射表征。采用紫外-可见分光光度法对1催化p-硝基苯酚醋酸酯(NA)的水解动力学性质进行了研究。结果表明:催化水解速率对底物(NA)及配合物浓度均呈一级反应,催化水解速率受酸碱平衡影响。