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ethyl lactate to 1,2-PDO is usually studied under heterogeneous catalytic conditions in the presence of hydrogen [ 1 – 7 ]. For example, Luo et al. reported that RuB/γ-Al 2 O 3 [ 1 – 3 ] and RuB/SBA-15 [ 4 ] are effective catalysts for the hydrogenation

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Introduction The hydrogenation of mononitroaromatic compounds to aromatic amines is ordinarily carried out in vapor-phase reactions using either a fixed bed or fluidized catalyst. However, the low vapor pressures and thermal

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Introduction The selective hydrogenation of α,β-unsaturated aldehydes to the corresponding unsaturated alcohol is important in fine chemistry, due to the added value of these products. It is well known that the C=C group is

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Introduction The hydrogenation of nitro compounds is an interesting industrial process for the manufacture of a great variety of oximes, amines and amides. Of these, cyclohexane oxime and ∊-caprolactam are important

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effective supports for Pt and Ru nanoparticles in the hydrogenation of unsaturated compounds [ 3 – 5 ]. Organic–inorganic nanocomposites take the advantages of organic polymers like flexibility, toughness, hydrophobicity and versatility for further

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Introduction The hydrogenation of aldehydes and ketones containing unsaturated C=C bonds is an important class of reactions to produce fine chemical compounds [ 1 – 5 ]. It was found that nickel, platinum and copper based

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Abstract  

Nano Ni–W catalysts with different tungsten contents prepared by mixing alkaline nickel carbonate with ammonium tungstate show high activity and good sulfur tolerance for hydrogenation of thiophene-containing ethylbenzene. The catalysts were characterized by XRD, TPR, SEM, Raman and BET. The results show that the activity of the catalysts for ethylbenzene hydrogenation is affected profoundly by W loading and the best result was obtained on catalyst with W/Ni ratio equal to 0.16. The increase of activity of the catalyst can be attributed to the interaction between Ni and W doped and the increase of the surface area of the catalyst.

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Abstract  

A Cu–Zn–Al catalyst was prepared by the co-precipitation method and was applied for the hydrogenation of dimethyl adipate. Selectivity to 1,6-hexanediol exceeding 99% was obtained at 99% conversion of dimethyl adipate. The catalyst was highly efficient and stable. The influences of the calcination temperature of the catalyst were studied.

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Abstract  

Effects of gaseous hydrogenation on crystallization behavior of melt-spun Mg63Pr15Ni22 amorphous ribbons have been investigated. The crystallization peak temperature T p1 shifted to higher temperature with increasing heating rate for the un-hydrogenated Mg63Ni22Pr15 metallic glass, however, it is nearly unchanged for the hydrogenated sample. The present work indicates that the crystallization is a nucleation-and-growth process for the un-hydrogenated Mg63Ni22Pr15 metallic glass. However, the crystallization of hydrogenated sample begins with nucleation and then diffusion-controlled growth takes place.

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Abstract  

The influence of trace oxygen on the catalytic activity of alumina supported Ru in the liquid phase hydrogenation of aromatic hydrocarbons was studied. The catalytic activity of Ru increased remarkably and the reproducibility was improved by removing dissolved oxygen from the reactant mixture and carefully refining the catalyst transfer procedure into the reactor to avoid exposure to air. Trace oxygen affected Ru very severely, but did not affect Rh, Pd, and Pt much. The activity of Ru was lower than those of Rh, Pd, and Pt in the presence of oxygen as reported in the literature; however, it was the highest when oxygen was removed carefully. Measurements of the adsorbed oxygen suggested that the activity seriously decreased when only the part of Ru surface was covered by oxygen. Bimetallic Pt–Ru catalysts demonstrated high activity even in the presence of oxygen.

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