Fe species were loaded by two different loading ways （absorption method and addition method） to investigate their effect on thermal properties of coke. The particulate coke reactivity of coke samples indicated that ...Fe species were loaded by two different loading ways （absorption method and addition method） to investigate their effect on thermal properties of coke. The particulate coke reactivity of coke samples indicated that the added sample showed higher catalytic activity than the adsorbed sample at first, owing to the decreased structure and properties of coke and more catalytic active sites caused by the strong interaction between Fe species and coke. The presence of Fe species in the added sample weakened the microstructure of coke, and the Fe species were easier to be reduced than those in the absorbed sample due to its different existence form in coke. With further increased loading of Fe species, the different existence positions of Fe species caused more decrease in surface active sites in the added sample than in the adsorbed sample, leading to lower catalytic activity of added sample when the total iron content exceeded 1%. The catalytic mechanism implied that there may be a catalytic dominant factor change in the reaction between the catalytic effect of iron species and carbon surface active sites in coke; the catalytic effect of iron species is dominant in the reaction at first, but the catalytic effect of carbon surface active sites is dominant in the reaction with the further increased loading amount of Fe species.展开更多
An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydr...An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydrothermal method and used as the support for a Ni catalyst for the dry reforming of methane （DRM） with CO2. ZrO2-ipch is a much better support than ZrO2-cs and the traditional ZrO2 irregular particles made by a simple precipitation method （ZrO2-ip）. The supported Ni catalyst on ZrO2-ipch （Ni/ZrO2-ipch） exhibited outstanding catalytic activity and coke-resistant stability compared to the ones on ZrO2-cs （Ni/ZrO2-cs） and ZrO2-ip （Ni/ZrO2-ip）. Ni/ZrO2-ip exhibited the worst catalytic performance. The origin of the significantly enhanced catalytic performance was revealed by characterization including XRD, N2 adsorption measurement （BET）, TEM, H2-TPR, CO chemisorption, CO2-TPD, XPS and TGA. The superior catalytic activity of Ni/ZrO2-ipch to Ni/ZrO2-cs or Ni/ZrO2-ip was ascribed to a higher Ni dispersion, increased reducibility, enhanced oxygen mo- bility, and more basic sites with a higher strength, which were due to the unique hierarchically structural morphology of the ZrO2-ipch support. Ni/ZrO2-ipch exhibited better stability for the DRM reaction than Ni/ZrO2-ip, which was ascribed to its higher resistance to Ni sintering due to a strengthened metal-support interaction and the confinement effect of the mesopores and coke deposition resistance. The higher coking resistance of Ni/ZrO2-ipch for the DRM reaction in comparison with Ni/ZrOz-ip orignated from the coke-removalabitity of the higher amount of lattice oxygen and more basic sites, confirmed by XPS and CO2-TPD analysis, and the stabilized Ni on the Ni/ZrO2-ipch catalyst by the confinement effect of the mesopores of the hierarchical ZrO2-ipch sup- port. The superior catalytic performance and coking resistance of the Ni/ZrO2-ipch catalyst makes it a promising candidate for synthesis gas production from the DRM reaction.展开更多
An environmental friendly carbonaceous material- carboresP （one of the Carbores series materials） was investigated for the production of MgO-C refractories in laboratory scale and field tests. The MgO-C specimens we...An environmental friendly carbonaceous material- carboresP （one of the Carbores series materials） was investigated for the production of MgO-C refractories in laboratory scale and field tests. The MgO-C specimens were produced with different CarboresP contents. The bulk density （180℃ × 48h）, CCS, apparent porosity （1000℃ ×3h ） and hot modulus of rupture （1400℃ ×0. 5h ） were tested and contrasted. The appropriate amount of carboresP was 1.0%. The amount of metallic additions can be partially substituted （reduced to 1.5% ）. The microstructure of resin-carboresP binder is anisotropic structure with high oxidation resistance and good thermal-shock stability. The Stress/strain curve indicates that the characteristic length, （LCH） of MgO-C brick with resin/CarboresP bonding has been improved, which means the MgO-C bricks have good mechanical flexibility and stresses absorbability. Field tests were done in slag line of a 40t LF-VD refining steel ladle using Resin/CarboresP bonded ＂ MT-14A MgO-C bricks. The result shows that the MgO-C bricks by ＂soft bonding＂ have good physical properties and excellent workability during production of the bricks . In contrast with traditional MgO-C brick used for secondary refining furnaces, the spalling tendency of the bricks could be reduced significantly. The average lining life of the resin/ CarboresP bricks has increased by 18. 4% comparing with the pure resin-bonded types.展开更多
文摘Fe species were loaded by two different loading ways （absorption method and addition method） to investigate their effect on thermal properties of coke. The particulate coke reactivity of coke samples indicated that the added sample showed higher catalytic activity than the adsorbed sample at first, owing to the decreased structure and properties of coke and more catalytic active sites caused by the strong interaction between Fe species and coke. The presence of Fe species in the added sample weakened the microstructure of coke, and the Fe species were easier to be reduced than those in the absorbed sample due to its different existence form in coke. With further increased loading of Fe species, the different existence positions of Fe species caused more decrease in surface active sites in the added sample than in the adsorbed sample, leading to lower catalytic activity of added sample when the total iron content exceeded 1%. The catalytic mechanism implied that there may be a catalytic dominant factor change in the reaction between the catalytic effect of iron species and carbon surface active sites in coke; the catalytic effect of iron species is dominant in the reaction at first, but the catalytic effect of carbon surface active sites is dominant in the reaction with the further increased loading amount of Fe species.
基金financially supported by the Joint Fund of Coal, set up by National Natural Science Foundation of China and Shenhua Co., Ltd.(U1261104)the National Natural Science Foundation of China (21276041)+3 种基金the Program for New Century Excellent Talents in University (NCET-12-0079)the Natural Science Foundation of Liaoning Province (2015020200)the Fundamental Research Funds for the Central Universities (DUT15LK41)the Science and Technology Development Program of Hangzhou (20130533B14)~~
文摘An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydrothermal method and used as the support for a Ni catalyst for the dry reforming of methane （DRM） with CO2. ZrO2-ipch is a much better support than ZrO2-cs and the traditional ZrO2 irregular particles made by a simple precipitation method （ZrO2-ip）. The supported Ni catalyst on ZrO2-ipch （Ni/ZrO2-ipch） exhibited outstanding catalytic activity and coke-resistant stability compared to the ones on ZrO2-cs （Ni/ZrO2-cs） and ZrO2-ip （Ni/ZrO2-ip）. Ni/ZrO2-ip exhibited the worst catalytic performance. The origin of the significantly enhanced catalytic performance was revealed by characterization including XRD, N2 adsorption measurement （BET）, TEM, H2-TPR, CO chemisorption, CO2-TPD, XPS and TGA. The superior catalytic activity of Ni/ZrO2-ipch to Ni/ZrO2-cs or Ni/ZrO2-ip was ascribed to a higher Ni dispersion, increased reducibility, enhanced oxygen mo- bility, and more basic sites with a higher strength, which were due to the unique hierarchically structural morphology of the ZrO2-ipch support. Ni/ZrO2-ipch exhibited better stability for the DRM reaction than Ni/ZrO2-ip, which was ascribed to its higher resistance to Ni sintering due to a strengthened metal-support interaction and the confinement effect of the mesopores and coke deposition resistance. The higher coking resistance of Ni/ZrO2-ipch for the DRM reaction in comparison with Ni/ZrOz-ip orignated from the coke-removalabitity of the higher amount of lattice oxygen and more basic sites, confirmed by XPS and CO2-TPD analysis, and the stabilized Ni on the Ni/ZrO2-ipch catalyst by the confinement effect of the mesopores of the hierarchical ZrO2-ipch sup- port. The superior catalytic performance and coking resistance of the Ni/ZrO2-ipch catalyst makes it a promising candidate for synthesis gas production from the DRM reaction.
文摘An environmental friendly carbonaceous material- carboresP （one of the Carbores series materials） was investigated for the production of MgO-C refractories in laboratory scale and field tests. The MgO-C specimens were produced with different CarboresP contents. The bulk density （180℃ × 48h）, CCS, apparent porosity （1000℃ ×3h ） and hot modulus of rupture （1400℃ ×0. 5h ） were tested and contrasted. The appropriate amount of carboresP was 1.0%. The amount of metallic additions can be partially substituted （reduced to 1.5% ）. The microstructure of resin-carboresP binder is anisotropic structure with high oxidation resistance and good thermal-shock stability. The Stress/strain curve indicates that the characteristic length, （LCH） of MgO-C brick with resin/CarboresP bonding has been improved, which means the MgO-C bricks have good mechanical flexibility and stresses absorbability. Field tests were done in slag line of a 40t LF-VD refining steel ladle using Resin/CarboresP bonded ＂ MT-14A MgO-C bricks. The result shows that the MgO-C bricks by ＂soft bonding＂ have good physical properties and excellent workability during production of the bricks . In contrast with traditional MgO-C brick used for secondary refining furnaces, the spalling tendency of the bricks could be reduced significantly. The average lining life of the resin/ CarboresP bricks has increased by 18. 4% comparing with the pure resin-bonded types.
