The simplest method of synthesizing metallic Cu (111) nanoparticles on the zinc–aluminum mixed oxides was found to be easily obtained by solid state grinding of all the three metal nitrates and organic compounds in suitable proportions. Organic compounds such as citric acid, formic acid, and hydrazine were used, which act as reducing agents for Cu. The catalysts were characterized by various physicochemical methods such as X-ray diffraction, X-ray fluorescence, temperature programmed reduction, high-resolution transmission electron spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy and N₂-physisorption. The use of citric acid resulted in Cu(111) nanoparticles with higher surface area and better dispersion on the surface of mixed oxides. The catalysts were used for the selective hydrogenation of furfural to furfuryl alcohol under vapor phase conditions. Among the various catalysts studied, citric acid-assisted catalysis showed better conversion with higher selectivity of desired product and deactivation free catalytic activity on stream more than 30 h.

中文翻译：

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柠檬酸辅助合成的氧化物体系负载的纳米铜催化剂在气相中将糠醛还原为糠醇

通过在适当比例下对所有三种金属硝酸盐和有机化合物进行固态研磨，很容易获得在锌-铝混合氧化物上合成金属Cu（111）纳米粒子的最简单方法。使用诸如柠檬酸，甲酸和肼的有机化合物，其充当Cu的还原剂。通过各种物理化学方法对催化剂进行了表征，例如X射线衍射，X射线荧光，程序升温还原，高分辨率透射电子光谱，X射线光电子能谱，场发射扫描电子显微镜和N _2。-物理吸附。柠檬酸的使用导致Cu（111）纳米粒子具有较高的表面积，并在混合氧化物的表面上具有更好的分散性。该催化剂用于在气相条件下将糠醛选择性加氢为糠醇。在研究的各种催化剂中，柠檬酸辅助的催化表现出更好的转化率，所需产物具有更高的选择性，并且在超过30小时的流中具有无失活的催化活性。