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乔明华, Yan Pei a, Pingjun Guo a, Minghua Qiao a, ∗, Hexing Li b, Shiqiang Wei c, Heyong He a, Kangnian Fan a
Journal of Catalysis 248 (2007) 303-310,-0001,():
-1年11月30日
Binary CoB and ternary CoFeB amorphous alloy catalysts with different Fe contents were prepared by the chemical reduction method. In liquid-phase hydrogenation of crotonaldehyde, incorporation of Fe into the CoB catalyst reduced the overall activity while effectively improving the selectivity and yield to crotyl alcohol. On the optimum CoFeB-3 catalyst with a nominal Fe/(Co+Fe) molar ratio of 0.6, the initial selectivity amounted to 71%, and the yield of crotyl alcohol reached 63%. It is found that the selectivity enhancement was due to the lower decrement in the intrinsic formation rate of crotyl alcohol compared with that of butanal, not to the increment in the activation of the C=O bond. Based on the characterizations, including X-ray photoelectron spectroscopy and X-ray absorption spectroscopy, and previous findings, the enhanced selectivity from Fe modification was tentatively attributed to an ensemble size effect.
CoB, Fe modification, Amorphous alloy, Crotonaldehyde, Crotyl alcohol, Hydrogenation, Ensemble size effect
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乔明华, Huarong Hu, a Minghua Qiao, a, ? Shuai Wang, a Kangnian Fan, ? Hexing Li, b Baoning Zong, c and Xiaoxin Zhang c
Journal of Catalysis 221(2004)612-618,-0001,():
-1年11月30日
The textural and structural properties of a skeletal Ni catalyst prepared by alkali leaching of aluminum from the rapidly quenched Ni50Al50 alloy have been investigated by elemental analysis (ICP-AES), nitrogen physisorption, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and H2 thermal desorption techniques. As compared to Raney Ni, such a skeletal catalyst has a residual Ni2Al3 phase, lower surface area, higher average pore diameter and porosity, larger mean crystallite size, and unit-cell parameter. These differences are attributable to the metastable character of the pristine rapidly quenched alloy and their relationship with the catalytic behavior is discussed and correlated.
Rapid quenching, Ni-Al alloy, Skeletal catalyst, Raney Ni, Texture, Structure, Hydrogenation
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乔明华, Huarong Hu, a Minghua Qiao, a, ∗ Shuai Wang, a Kangnian Fan, ∗ Hexing Li, b Baoning Zong, c and Xiaoxin Zhang c
Journal of Catalysis 221 (2004) 612-618,-0001,():
-1年11月30日
The textural and structural properties of a skeletal Ni catalyst prepared by alkali leaching of aluminum from the rapidly quenched Ni50Al50 alloy have been investigated by elemental analysis (ICP-AES), nitrogen physisorption, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and H2 thermal desorption techniques. As compared to Raney Ni, such a skeletal catalyst has a residual Ni2Al3 phase, lower surface area, higher average pore diameter and porosity, larger mean crystallite size, and unit-cell parameter. These differences are attributable to the metastable character of the pristine rapidly quenched alloy and their relationship with the catalytic behavior is discussed and correlated.
Rapid quenching, Ni-Al alloy, Skeletal catalyst, Raney Ni, Texture, Structure, Hydrogenation
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【期刊论文】Solution route to single crystalline SnO platelets with tunable shapes
乔明华, Shuai Wang, a Songhai Xie, a Hexing Li, b Shirun Yan, a Kangnian Fana and Minghua Qiao, *a
,-0001,():
-1年11月30日
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乔明华, Huarong Hu a, Fuzhong Xie a, Yan Pei a, Minghua Qiao a, ∗, Shirun Yana, Heyong He a, Kangnian Fan a, Hexing Li b, Baoning Zong c, Xiaoxin Zhang c
Journal of Catalysis 237 (2006) 143-151,-0001,():
-1年11月30日
Skeletal Ni catalysts (RQ Ni) prepared by alkali leaching of rapidly quenched Ni–Al alloys have been systematically characterized, focusing on the effect of the cooling rate during alloy preparation. It is found that the residual Al content, texture, structure, surface hydrogen species, and active sites of the RQ Ni catalysts can be controlled by the cooling rate of the Ni–Al alloys. In liquid-phase hydrogenation of 2-ethylanthraquinone (eAQ), the RQ Ni catalyst with higher cooling rate favors hydrogenation of the carbonyl group and retards the saturation of the aromatic ring and the formation of the degradation products, thus leading to a higher yield of H2O2. Based on the characterizations, the improved selectivity is ascribed to the dominant population of strongly chemisorbed hydrogen, which is inactive for the hydrogenation of the aromatic ring, along with the electronic interaction between residual metallic Al and Ni, favoring a carbonyl group-bonded configuration of eAQ on the catalyst.
Skeletal Ni, Rapid quenching, Cooling rate, Ni-Alalloy, eAQ, Hydrogenation, H2O2
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