Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over An Ultrafine Co-B Amorphous Catalyst

A novel Co-B amorphous alloy catalyst in the form of ultrafine particles was prepared by chemical reduction of CoCl2 with aqueous NaBH4, which exhibited excellent activity and selectivity during the hydrogenation of cinnamaldehyde to cinnamyl alcohol in liquid phase. The optimum yield of cinnamyl alcohol was 87.6%, much better than the yield of using Raney Ni, Raney Co and other Co-based catalysts.

Hydroformylation of 1-Octene over Nanotubular TiO2-supported Amorphous Co-B Catalysts

TiO2 nanotubes supported amorphous Co-B（Co-B/TNTs） catalyst was prepared via impregnation- chemical reduction procedure. The catalyst was characterized with transmission electron microscopy（TEM）, ammonia temperature-programmed desorption（NH3-TPD）, thermogravimetry-differential thermal analysis（TG-DTA）, Fourier transform infrared spectroscopy（FTIR） and Raman spectroscopy. The effects of temperature and ratio of CO to HE on the hydroformylation of 1-octene were studied. At an optimized reaction temperature（150 ℃） and volume ratio of CO to H2（2：1）, the conversion of 1-octene can reach 97.4% with a selectivity of 23.1% for total aldehydes and n/i-aldehyde molar ratio of 40：60. To obtain higher selectivity for linear aldehydes, Co-B/TNTs modified with triphenylphosphine for the hydroformylation of 1-octene were investigated. When molar ratio of P/Co was 4, the yield of total aldehydes was the highest（31.6%） with a good selectivity for linear product（n/i-aldehyde molar ratio was 70：30）. In recycle use, the Co-B/TNTs catalyst modified with triphenylphosphine could be reused five times without reducing the activity and selectivity obviously. For a comparative study, all the Co-B/TNTs to catalyze the hydroformylation of other olefins exhibited high conversion under the optimized conditions.

Highly selective CO methanation over amorphous Ni-Ru-B/ZrO_2 catalyst

Amorphous Ni-Ru-B/ZrO2 catalyst was prepared by the means of chemical reduction, and selective CO methanation as a strategy for CO removal in fuel processing applications was investigated over the amorphous Ni-Ru-B/ZrO2 catalyst. The result showed that, at the temperature of 210-230 ℃, the catalyst was shown to be capable of reducing CO in a hydrogen-rich reformate to less than 10 ppm, while keeping the CO2 conversion below 1.55% and the hydrogen consumption below 6.50%. ？2009 Xin Fa Dong. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Study on the Nanosized Amorphous Ru-Fe-B/ZrO_2 Alloy Catalyst for Benzene Selective Hydrogenation to Cyclohexene

A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize and the amorphous character as well as to its textural character. In addition, the concentration of zinc ions, the content of ZrO2 in the slurry, and the pretreatment of the catalyst were found to be effective in improving the activity and the selectivity of the catalyst.

Effect of Lanthanum on Performance of RuB Amorphous Alloy Catalyst for Benzene Selective Hydrogenation

The effect of La on the performance of a supported RuB amorphous alloy catalyst for benzene selective hydrogenation was studied by means of activity and selectivity tests, such as HRTEM, SAED, XPS, and XRD. The results show that the addition of La to RuB amorphous alloy catalyst can evidently increase the activity and improve the thermal stability of RuB amorphous alloy to refrain its crystallization. The promoting effect of La on the activity of RuB amorphous alloy catalyst is because of the high dispersion of the active components.

Selective CO methanation over amorphous Ni-Ru-B/ZrO_2 catalyst for hydrogen-rich gas purification

Amorphous Ni-Ru-B/ZrO2 catalysts were prepared by chemical reduction method. The effects of Ni-Ru-B loading and Ru/Ni mole ratio on the catalytic performance for selective CO methanation from reformed fuel were studied, and the catalysts were characterized by BET, ICP, XRD and TPD. The results showed that Ru strongly affected the catalytic activity and selectivity by increasing the thermal stability of amorphous structure, promoting the dispersion of the catalyst particle, and intensifying the CO adsorption. For the catalysts with Ru/Ni mole ratio under 0.15, the CO methanation conversion and selectivity increased significantly with the increasing Ru/Ni mole ratio. Among all the catalysts investigated, the 30 wt% Ni-Ru-B loading amorphous Ni61Ru9B30/ZrO2 catalyst with 0.15 Ru/Ni mole ratio presented the best catalytic performance, over which higher than 99.9% of CO conversion was obtained in the temperature range of 230℃-250℃, and the CO2 conversion was kept under the level of 0.9%.

A Novel Ultrafine Ru-B Amorphous Alloy Catalyst for Glucose Hydrogenation to Sorbitol

An ultrafine Ru-B amorphous alloy catalyst was prepared by chemical reduction with KBH4 in aqueous solution, which exhibited perfect selectivity to sorbitol (~100%) and very high activity during the liquid phase glucose hydrogenation, much higher than the corresponding crystallized Ru-B, the pure Ru powder, and Raney Ni catalysts. The correlation of the catalytic activity to both the structural and surface electronic characteristics was discussed briefly.

Amorphous TiO_2-supported Keggin-type ionic liquid catalyst catalytic oxidation of dibenzothiophene in diesel

Supported ionic liquid(IL) catalysts [Cmim]PMoO/Am TiO(amorphous TiO) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization(ECODS) system. Characterizations such as FTIR, DRS,wide-angle XRD, Nadsorption–desorption and XPS were applied to analyze the morphology and Keggin structure of the catalysts. In ECODS with hydrogen peroxide as the oxidant, it was found that ILs with longer alkyl chains in the cationic moiety had a better effect on the removal of dibenzothiophene. The desulfurization could reach 100% under optimal conditions, and GC–MS analysis was employed to detect the oxidized product after the reaction. Factors affecting the desulfurization efficiencies were discussed, and a possible mechanism was proposed. In addition, cyclic experiments were also conducted to investigate the recyclability of the supported catalyst. The catalytic activity of [Cmim]PMoO/Am TiOonly dropped from 100% to 92.9% after ten cycles, demonstrating the good recycling performance of the catalyst and its potential industrial application.

Effects of Cerium Dopant on Ni-B Amorphous Alloy Catalysts Used in 2-Ethylanthraquinone Hydrogenation

A series of Ce-doped Ni-B amorphous alloy catalysts were prepared by a KBH_4 reduction method, characterized by ICP, BET, XRD, H_2-chemisorption, H_2-TPD, etc., and tested in the hydrogenation of 2-ethylanthraquinone. The results of characterization show that with the addition of Ce the amount of H_2-chemisorption and H_2-TPD areas first increases markedly and then decreases with the maximum appears at the atomic ratio of Ce to Ni of 0.036. The hydrogenation activity also shows the same trend. The effects of Ce are attributed to its dispersion of Ni particles, resulting in the formation of more surface Ni centers. However, much higher Ce contents may result in the decrease of the surface Ni contents. After heat treatment at higher temperatures, the amorphous structure of Ni-B is destroyed.

Ni-B/TiO_2 Amorphous Catalyst Used in Heavy Arenes of Petrochemicals Hydrogenation

A supported Ni-B/TiO2 amorphous catalyst was prepared by impregnation and reduction. It was characterized by XRD, SAED, DSC, XPS, etc.. The catalytic activity of catalyst was measured through the hydrogenation of heavy arenes in petrochemicals for the first time.

Preparation and Application of Supported Amorphous Alloy Catalyst CoP/TiO_2

A new supported amorphous catalyst CoP/TiO2 was prepared by chemical reduction and characterized by ICP, XRD, TEM, BET and DSC. Its application in decomposing PH3 to high purity phosphor and its catalytic activity were studied. The decomposition rate is over 95% at 450 ℃. For comparison, unsupported CoP amorphous catalyst was prepared by the same method. The result suggests that CoP/TiO2 exhibits higher thermal stability and catalytic activity than CoP, which is attributed to the high dispersion of CoP alloy particles on the support-TiO2.

Preparation of Uniform Ni-B Amorphous Alloy Catalyst on CNTs and its Performance for Acetylene Selective Hydrogenation

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and better catalytic activity and ethylene selectivity in the acetylene hydrogenation reaction.

ACTIVATION MECHANISM OF AMORPHOUS Ni63Zr32La5 ALLOY HYDROGENATION CATALYST

The catalytic activity of amorphous Ni_63 Zr_32 La_5 ribbon for hydrogenation of ethyne to ethylene can be greatly enhanced when the alloy ribbon is pretreated with dilute acid solution,heated under negative atmosphere pressure and subjected to hydrogen reduction successively. The change of surface state of the ribbon during the activation has been analysed by AES and XPS. The surface of as-received ribbon is covered with a thin film of La_2 O_3. After pretreatment. the surface concentrations of both Ni and Zr increase obviously, whereas the surface concentration of La decreases markedly.Finally, on the surface of activated catalyst the Ni and NiO disperse finely on the matrix consisting of oxides of both Zr and La and a small amount of fluorides of Zr and La.

Amorphous urchin-like copper@nanosilica hybrid for efficient CO_(2) electroreduction to C2+ products

Currently most of research efforts for selective electrocatalysis CO_(2) reduction to C2+products have relied on crystalline Cu-based catalysts;amorphous Cu with abundant low-coordinated atoms holds greater promise for this conversion yet remains relatively underexplored.Here we report an amorphous urchin-like Cu@nanosilica hybrid synthesized by electrostatic coupling Si polyanions with Cu salt in hydrothermal processes.The Cu@nanosilica electrocatalyst displays excellent CO_(2) electroreduction activity and selectivity with a Faradic efficiency of 70.5%for C2+product production,and higher stability compared to the crystalline Cu counterpart.The solar-driven CO_(2) electrolysis yields an energy efficiency of 20%for C2+product production.Mechanism study reveals that the urchin-like Cu@nanosilica catalyst with amorphous Cu/Cu^(+)dispersion enhances CO_(2) adsorption and activation to facilitate generation of CO_(2)^(-)*and possible CO^(*)intermediates,and suppresses hydrogen evolution concurrently.The combined effects of both aspects promote efficient C2+product production from CO_(2) electroreduction.

铬锰双金属催化剂催化HMF制备FDCA的研究

采用浸渍法制备了铬锰(Cr-Mn)双金属催化剂并用于5-羟甲基糠醛(HMF)催化氧化制备2,5-呋喃二甲酸(FDCA)。研究了不同铬掺杂比例对催化效果的影响,并探索了HMF催化氧化制备FDCA的最佳反应条件。结果表明,在最佳反应条件下HMF转化率为99%,FDCA产率达到87.9%;Cr-Mn双金属催化剂表现出优异的催化性能,同时具有良好的稳定性,循环4次后仍保持较高的活性。该非贵金属催化剂为催化HMF制备FDCA提供了一种廉价、简便的制备方法。

Mo掺杂Co-B非晶态合金的制备及催化硼氢化钠水解制氢性能

硼氢化钠作为金属氢化物,因具有储氢密度大、产氢纯度高、反应温度低、储存运输安全、能源循环利用率高等特点,成为目前产氢技术研究领域的热点之一。硼氢化钠水解产氢技术的关键在于催化剂。本研究采用化学还原法制备了掺杂助催剂Mo的三元非晶态Mo-Co-B纳米合金粉末,并将其用于催化硼氢化钠水解制氢。采用X射线衍射(XRD)仪、场发射透射电镜(FETEM)、扫描电镜(SEM)、能谱分析(EDS)对样品的结构、表面形貌、元素成分进行了表征。通过排水法进行NaBH 4溶液水解产氢反应,研究了催化剂的催化性能。结果表明,Mo的适量掺入能显著减小催化剂的粒径,增大其比表面积,提高Co-B催化剂的催化性能,但过量的Mo会导致粉末中的金属氧化物增多,不利于催化。当Mo/Co物质的量比为0.05时,催化剂表现出最佳的催化活性。此外,研究了催化剂用量、反应温度、NaBH 4浓度等因素对NaBH 4溶液水解产氢反应的影响。

Co-B/γ-Al_2O_3非晶态催化剂的制备及其催化乳酸乙酯液相加氢性能

采用浸渍-还原法制备了负载型Co-B/γ-Al2O3非晶态合金催化剂,并将其应用于乳酸乙酯液相加氢制备1,2-丙二醇(1,2-PDO)反应中,研究了其催化加氢性能.采用电感耦合等离子体(ICP)发射光谱仪、X射线衍射(XRD)仪、透射电子显微镜(TEM)、差示扫描量热(DSC)、X射线光电子能谱(XPS)等手段对催化剂的性能进行了表征,考察了制备条件对催化剂性能的影响.结果表明,新鲜的Co-B/γ-Al2O3催化剂具有非晶态结构,Co-B均匀地分散在载体γ-Al2O3上.随着Co负载量的增加,催化剂的热稳定性提高,催化剂表面Co/B原子比增加.当金属Co理论负载量为30%(质量分数,w)时,Co-B/γ-Al2O3催化剂表现出最高的加氢催化性能,在160°C,氢气压力为6.0 MPa条件下反应9 h,乳酸乙酯的转化频率(TOF)为1.41 h-1,转化率达到93.63%,1,2-丙二醇的选择性达到96.10%.催化剂的加氢性能取决于其分散均匀的Co-B纳米粒子、较高的表面Co/B原子比及Co和B之间的电子转移效应.

Design of earth-abundant amorphous transition metal-based catalysts for electrooxidation of small molecules:Advances and perspectives

Electrochemical oxidation of small molecules(e.g.,water,urea,methanol,hydrazine,and glycerol)has gained growing scientific interest in the fields of electrochemical energy conversion/storage and environmental remediation.Designing cost-effective catalysts for the electrooxidation of small molecules(ESM)is thus crucial for improving reaction efficiency.Recently,earth-abundant amorphous transition metal(TM)-based nanomaterials have aroused souring interest owing to their earth-abundance,flexible structures,and excellent electrochemical activities.Hundreds of amorphous TM-based nanomaterials have been designed and used as promising ESM catalysts.Herein,recent advances in the design of amorphous TM-based ESM catalysts are comprehensively reviewed.The features(e.g.,large specific surface area,flexible electronic structure,and facile structure reconstruction)of amorphous TM-based ESM catalysts are first analyzed.Afterward,the design of various TM-based catalysts with advanced strategies(e.g.,nanostructure design,component regulation,heteroatom doping,and heterostructure construction)is fully scrutinized,and the catalysts’structure-performance correlation is emphasized.Future perspectives in the development of cost-effective amorphous TM-based catalysts are then outlined.This review is expected to provide practical strategies for the design of next-generation amorphous electrocatalysts.