Kinetic model ofCO oxidation on nonuniform surface analyzed regardingCOads spillover, 2. homotopic method. Effect ofm1 surface portion

The homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCO ₂ spillover. Diagrams of steady states depending on the portion of surface patchm ₁ at various temperatures and pressure ratiosP(O ₂)/P(CO) have been constructed. The ratios of different type patches corresponding to the maximum overall reaction rate have been found.     

Olefin metathesis in room temperature ionic liquids using imidazolium-tagged ruthenium complexes

New recyclable imidazolium-tagged ruthenium catalysts have been developed to perform olefin metathesis in room temperature ionic liquids (RTILs). High level of recyclability combined with a high reactivity were obtained in the ring-closing metathesis (RCM) of a variety of di- or tri-substituted and/or oxygen-containing dienes. Extremely low residual ruthenium levels were detected in the RCM products (average of 7.3 ppm per run). Several examples of olefin cross-metathesis (CM) have been also studied.     

Synthesis and catalytic activity of new chiral unsymmetrical Mn(III)-Schiff-base complexes containing salicylaldehyde and 1-(2-hydroxyphenyl)ketone units

Two new chiral unsymmetrical (non-C₂-symmetric) Schiff-base ligands containing salicylaldehyde and 1-(2-hydroxyphenyl)ketone units were synthesized from (R,R)-1,2-diphenylethylenediamine as the chiral diamine using a stepwise approach. The Mn(III) complexes of the ligands were subsequently used as catalysts in asymmetric epoxidation of unfunctionalized alkenes and the results were compared with those obtained using typical C₂-symmetric Mn(III)–salen complexes. Possible reasons for the differences in reactivity and selectivity between the two types of catalysts are briefly discussed.     

催化剂和供氢剂对渣油模型化合物裂化反应选择性的影响

供氢剂与分散性催化剂协同作用对于传统的煤液化体系和渣油加氢裂化体系非常重要。通过活化分子氢及煤分子，使液化反应在较低的温度下进行以减少副反应，继而提高氢转移效率，增加液体产物产率。供氢剂和催化剂起促进煤分子裂化的作用。将供氢剂与催化剂的协同作用应用于渣油加     

Formation of supported size-controlled nanoparticles of sulfated zirconia

Methods of the preparation of catalysts for alkane skeletal isomerization based on uniform nanoparticles of sulfated zirconia anchored to different supports were investigated. These catalysts were characterized by using the ICP, HRTEM and BET techniques. The activities of the catalysts in the reaction of n-butane isomerization were measured and compared with those of bulk catalysts.     

CONVERSION OF METHANE AND CARBON DIOXIDE TO AROMATICS OVER CHROMIUM-BASED CATALYSTS:SELECTIVITY AND YIELD OF MAIN PRODUCTS

在８４０℃，０．５ＭＰａ，ＣＨ４／ＣＯ２摩尔比为１．４，接触时间（Ｗ／Ｆ）为０．７９ｈ·ｇ·Ｌ－ｌ的条件下，甲烷和二氧化碳在７．５ｗｔ％Ｃｒ／５．０ｗｔ％Ｎａ／ＳｉＯ２催化剂上共活化得到了４．８％的Ｃ２选择性，４８．７％的芳烃选择性及１．９％的芳烃收率。在钠修饰的铬基催化剂上，成功地一步实现了ＣＨ４和ＣＯ２转化为乙烯及中间物乙烯聚合为芳烃的过程     

Intergrowth between V2O5 and TiO2 (anatase): High resolution electron microscopy evidence

V₂O₅/TiO₂ (anatase) with 5 and 20 wt.% loadings of V₂O₅ have been studied using high resolution electron microscopy. This has provided the first direct evidence for the formation of a coherent interfacial boundary between two crystalline TiO₂ and V₂O₅ phases. The type of the interfacial stacking was found to be similar for all the samples, whereas the length of the boundary formed depended on the V₂O₅ loading. A model for the atomic arrangement of this boundary based on a comparison of structural positions of oxygen and metal atoms in the crystal lattices of both phases is proposed.     

Immobilization of Polymer-Stabilized Noble Metal Colloids and Their Catalytic Properties for Hydrogenation of Olefins

Polymer-stabilized noble metal colloids were efficiently immobilized on silica by the addition of organic acids under mild conditions. The function of organic acids in the immobilization was studied by infrared spectroscopy. Transmission electron micrographs indicate that the immobilized colloids have a controlled particle size and size distribution. They serve as catalysts in the hydrogenation of cyclohexene and cyclopentadiene, the results of which show that this new type of immobilized colloid has high selectivity and good stability.     

Hydrogermylation of phenylacetylene catalyzed by onium chlorometallates

Triethylbenzylammonium chlorometallates [Et₃NCH₂Ph][MCl_n]^m? (M = Pt, Pd, Rh, Ir, Fe, Co, Cu, m = 1–3, n = 3–6), polymer-anchored ionic metal complexes [?—CH₂PBu₃][MCl_n]^n? and some other chlorometallates and complexes of platinum, rhodium, ruthenium and osmium were studied as catalysts in the hydrogermylation of phenylacetylene with triethylgermane. All the complexes containing platinum, palladium and rhodium were found to be effective catalysts. The cis/trans ratio of the products obtained is determined by the metal atom involved and decreases in the following order: Ir > Rh ? Pd > Pt.