The partial oxidation of methane to syngas over Ni/ZrO2 catalyst irradiated by ndcrowave has been studied. Compared with a conventional heating mode, the temperature of the catalytic bed is much lower and there is a h...The partial oxidation of methane to syngas over Ni/ZrO2 catalyst irradiated by ndcrowave has been studied. Compared with a conventional heating mode, the temperature of the catalytic bed is much lower and there is a higher selectivity of CO and H2 with microwave irradiation.展开更多
The directly selective hydrogenolysis of xylitol to ethylene glycol(EG) and 1,2-propylene glycol(1,2-PDO)was performed on Cu–Ni–ZrO_2 catalysts prepared by a co-precipitation method. Upon optimizing the reaction con...The directly selective hydrogenolysis of xylitol to ethylene glycol(EG) and 1,2-propylene glycol(1,2-PDO)was performed on Cu–Ni–ZrO_2 catalysts prepared by a co-precipitation method. Upon optimizing the reaction conditions(518 K, 4.0 MPaH_2 and 3 h), 97.0% conversion of xylitol and 63.1% yield of glycols were obtained in water without extra inorganic base. The catalyst still remained stable activity after six cycles and above 80% total selectivity of glycols was obtained when using 20.0% xylitol concentration. XRD, TEM and ICP results indicated that Cu–Ni–ZrO_2 catalysts possess favorable stability. Cu and Ni are beneficial to the cleavage of C–O and C–H bond, respectively. To reduce the hydrogen consumption, isopropanol was added as in-situ hydrogen source and 96.4% conversion of xylitol with 43.6% yield of glycols were realized.展开更多
The structures of plasma-sprayed ZrO_2/(Ni/AI) interface before and after hot isostatic pressing (HIP) treatment were studied by TEM,ED and X-ray diffraction analysis.Plasma-sprayed ZrO_2/(Ni/AI) interfacial region is...The structures of plasma-sprayed ZrO_2/(Ni/AI) interface before and after hot isostatic pressing (HIP) treatment were studied by TEM,ED and X-ray diffraction analysis.Plasma-sprayed ZrO_2/(Ni/AI) interfacial region is of definite thickness and consists of multi-phase structures. Amorphous ZrO_2 sublayer,amorphous plus microcrystalline ZrO_2 sublayer and NiO were found in the interface.NiO phase formed by the reaction between ceramic coating and metallic substrate in local regions.However.the thickness and amount of NiO trended to increase and the distribution of NiO particles trended continuously when the coating was subjected to HIP treatment.HIP treatment can accelerate the diffusion of atoms in the interfacial region.展开更多
A series of monolithic Ni/CeO_2-ZrO_2/γ-Al_2O_3 catalysts for the POM reaction were prepared. The activity test shows that the catalyst has the best performance when CeO_2-ZrO_2 content is 8 wt%.The synergistic actio...A series of monolithic Ni/CeO_2-ZrO_2/γ-Al_2O_3 catalysts for the POM reaction were prepared. The activity test shows that the catalyst has the best performance when CeO_2-ZrO_2 content is 8 wt%.The synergistic actions between CeO_2-ZrO_2 and γ-Al_2O_3 improve highly catalytic activity by increasing CH_4 conversion, H_2 and CO selectivity. XPS analysis of the used catalyst indicates that there coexist Ce^(4+) and Ce^(3+).展开更多
Pure tetragonal 10-20-nm-size zirconia-based Ni-P composite coating was developed. The physicochemical and electrochemical characteristics including corrosion resistance of the coating were investigated. The Ni-P-nano...Pure tetragonal 10-20-nm-size zirconia-based Ni-P composite coating was developed. The physicochemical and electrochemical characteristics including corrosion resistance of the coating were investigated. The Ni-P-nano-tetragonal zirconia coating was partially crystalline having face-centered cubic phase. The coating had very high corrosion resistance due to its dense compact morphology and low surface roughness. The Ni-P-nano-tetragonal zirconia coatings exhibited a cathodic shift of open-circuit potential(OCP) in the range from-0.340 to-0.520 V. A high polarization resistance of the order of 13.2 kΩ/cm^2 and low corrosion current density of 3.9 μA/cm^2 were achieved due to the effective incorporation of zirconia into the coating.展开更多
文摘The partial oxidation of methane to syngas over Ni/ZrO2 catalyst irradiated by ndcrowave has been studied. Compared with a conventional heating mode, the temperature of the catalytic bed is much lower and there is a higher selectivity of CO and H2 with microwave irradiation.
基金financial supports provided by the National Natural Science Foundation of China (21406255)the Shanghai Science and Technology Committee (16dz1207200)the Youth Innovation Promotion Association CAS (2015231)
文摘The directly selective hydrogenolysis of xylitol to ethylene glycol(EG) and 1,2-propylene glycol(1,2-PDO)was performed on Cu–Ni–ZrO_2 catalysts prepared by a co-precipitation method. Upon optimizing the reaction conditions(518 K, 4.0 MPaH_2 and 3 h), 97.0% conversion of xylitol and 63.1% yield of glycols were obtained in water without extra inorganic base. The catalyst still remained stable activity after six cycles and above 80% total selectivity of glycols was obtained when using 20.0% xylitol concentration. XRD, TEM and ICP results indicated that Cu–Ni–ZrO_2 catalysts possess favorable stability. Cu and Ni are beneficial to the cleavage of C–O and C–H bond, respectively. To reduce the hydrogen consumption, isopropanol was added as in-situ hydrogen source and 96.4% conversion of xylitol with 43.6% yield of glycols were realized.
文摘The structures of plasma-sprayed ZrO_2/(Ni/AI) interface before and after hot isostatic pressing (HIP) treatment were studied by TEM,ED and X-ray diffraction analysis.Plasma-sprayed ZrO_2/(Ni/AI) interfacial region is of definite thickness and consists of multi-phase structures. Amorphous ZrO_2 sublayer,amorphous plus microcrystalline ZrO_2 sublayer and NiO were found in the interface.NiO phase formed by the reaction between ceramic coating and metallic substrate in local regions.However.the thickness and amount of NiO trended to increase and the distribution of NiO particles trended continuously when the coating was subjected to HIP treatment.HIP treatment can accelerate the diffusion of atoms in the interfacial region.
文摘A series of monolithic Ni/CeO_2-ZrO_2/γ-Al_2O_3 catalysts for the POM reaction were prepared. The activity test shows that the catalyst has the best performance when CeO_2-ZrO_2 content is 8 wt%.The synergistic actions between CeO_2-ZrO_2 and γ-Al_2O_3 improve highly catalytic activity by increasing CH_4 conversion, H_2 and CO selectivity. XPS analysis of the used catalyst indicates that there coexist Ce^(4+) and Ce^(3+).
文摘Pure tetragonal 10-20-nm-size zirconia-based Ni-P composite coating was developed. The physicochemical and electrochemical characteristics including corrosion resistance of the coating were investigated. The Ni-P-nano-tetragonal zirconia coating was partially crystalline having face-centered cubic phase. The coating had very high corrosion resistance due to its dense compact morphology and low surface roughness. The Ni-P-nano-tetragonal zirconia coatings exhibited a cathodic shift of open-circuit potential(OCP) in the range from-0.340 to-0.520 V. A high polarization resistance of the order of 13.2 kΩ/cm^2 and low corrosion current density of 3.9 μA/cm^2 were achieved due to the effective incorporation of zirconia into the coating.
