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.

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.

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%.

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.

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.

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.

Effect of TiO_2 Support on the Composition, Morphology and Catalytic Property of the NiB Amorphous Alloy Catalyst

Both the unsupported and supported NiB amorphous alloy catalysts (NiB and NiB/TiO2) were prepared by the chemical reduction method. Their catalytic activities were tested by the hydrogenation of sulfolene. The interactions between the NiB alloy and TiO2 were discussed for the first time by using XRD, ICP, SEM and TEM.

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.

Earth-abundant amorphous catalysts for electrolysis of water

The generation of hydrogen through the electrolysis of water has attracted attention as a promising way to produce and store energy using renewable energy sources.In this process,a catalyst is very important to achieve a high‐energy conversion efficiency for the electrolysis of water.A good catalyst for water electrolysis should exhibit high catalytic activity,good stability,low cost and good scalability.Much research has been devoted to developing efficient catalysts for both the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Traditionally,it has been accepted that a material with high crystallinity is important to serve as a good catalyst for HER and/or OER.Recently,catalysts for HER and/or OER in the electrolysis of water splitting based on amorphous materials have received much interest in the scientific community owing to the abundant unsaturated active sites on the amorphous surface,which form catalytic centers for the reaction of the electrolysis of water.We summarize the recent advances of amorphous catalysts for HER,OER and overall water splitting by electrolysis and the related fundamental chemical reactions involved in the electrolysis of water.The current challenges confronting the electrolysis of water and the development of more efficient amorphous catalysts are also discussed.

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.

Identification of the structure of Ni active sites for ethylene oligomerization on an amorphous silica-alumina supported nickel catalyst

The structure of Ni active sites supported on amorphous silica-alumina supports with different contents of Al_(2)O_(3)loadings in relation to their activities in ethylene oligomerization were investigated.Two kinds of Ni sites were detected by in situ FTIR-CO and H_(2)-TPR experiments,that are Ni^(2+)cations as grafted on weak acidic silanols and Ni^(2+)cations at ion-exchange positions.The ethylene oligomerization activities of these Ni/ASA catalysts were found an ascending tendency as the Al_(2)O_(3)loading decreased,which could be attributed to the enriched concentration of Ni^(2+)species on acidic silanols with a weaker interaction with the amorphous silica-alumina support.These Ni^(2+)species were more easily to be evolved into Ni^(+)species,which has been identified to be the active sites of ethylene oligomerization.Thus,it seems reasonable to conclude that Ni^(2+)species grafted on acidic silanols were the precursors of active sites.

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.

Amorphous CoSnO_3@rGO nanocomposite as an efficient cathode catalyst for long-life Li-O_2 batteries

An amorphous CoSnO3@rGO nanocomposite fabricated using a surfactant‐assisted assembly method combined with thermal treatment served as a catalyst for non‐aqueous lithium‐oxygen(Li‐O2)batteries.In contrast to the specific surface area of the bare CoSnO3 nanoboxes(104.3 m2 g–1),the specific surface area of the CoSnO3@rGO nanocomposite increased to approximately 195.8 m2 g–1 and the electronic conductivity also improved.The increased specific surface area provided more space for the deposition of Li2O2,while the improved electronic conductivity accelerated the decomposition of Li2O2.Compared to bare CoSnO3,the overpotential reduced by approximately 20 and 60 mV at current densities of 100 and 500 mA g?1 when CoSnO3@rGO was used as the catalyst.A Li‐O2 battery using a CoSnO3@rGO nanocomposite as the cathode catalyst cycled indicated a superior cyclic stability of approximately 130 cycles at a current density of 200 mA g–1 with a limited capacity of 1000 mAh g–1,which is 25 cycles more than that of the bare amorphous CoSnO3 nanoboxes.

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 Ni_(63)Zr_(32)La_5 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.

A Pd-Fe-B/γ-Al2O3 Amorphous Alloy Catalyst for Hydrogenation of Chloronitrobenzene to Chloroaniline

A Pd-Fe-B/γ-Al2O3 amorphous alloy catalyst was prepared by impregnation and chemical reduction with borohydrine aqueous solution. The catalyst was characterized by X-ray diffraction（XRD）, scanning electron microscope（SEM）, differential scanning calorimetry（DSC） and elecdes design suite（EDS） and was used for catalytic hydrogenation of 5-nitro-2-chloro-2＇, 4＇-dimethylbenzenesulfonanilide （NCD）. The amorphous alloy catalyst shows significantly high activity and selectively for hydrogenation of NCD to 5-Amino-2-chloro- 2＇, 4＇-dimethyibenzenesuifonanilide （ACD）.

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。

Ru-B/SiO_2非晶态催化剂应用于液相葡萄糖加氢制山梨醇

采用浸渍法结合KBH4还原法制备了Ru B/SiO2 非晶态催化剂 (3 1 4 %Ru) ,并将其用于液相葡萄糖加氢制山梨醇反应 .结果表明 ,该催化剂具有良好的热稳定性 ,且其催化活性远高于RaneyNi和Ni B/SiO2 非晶态催化剂 ,山梨醇的选择性接近于 1 0 0 % ,显示出良好的工业化应用前景 .通过与晶态Ru B/SiO2 及Ru/SiO2 的催化活性进行比较 ,并结合ICP ,XRD ,DSC ,SEM ,XPS及氢吸附等表征结果 。