In this paper, a series of hexaaluminate oxides, LaMAl 11 O 19-δ (M=Fe, Co, Ni, Mn and Cu), were prepared using transition metals M to substitute Al in the hexaaluminate lattices. XRD analyses indicated that the seri...In this paper, a series of hexaaluminate oxides, LaMAl 11 O 19-δ (M=Fe, Co, Ni, Mn and Cu), were prepared using transition metals M to substitute Al in the hexaaluminate lattices. XRD analyses indicated that the series of hexaaluminates had almost the same magnetoplumbite crystal structure, however, they exhibted different reducibility and catalytic activities for CO 2 reforming of methane to synthesis gas. Among the LaMAl 11 O 19-δ samples, LaNiAl 11 O 19-δ showed the best catalytic activity for the reaction at 1 053 K for 2 h, the conversion of CH 4 and CO 2 was 98.8% and 97.6%, respectively, and the catalytic activities of rest Msubstituted catalysts were extremely lower than that of LaNiAl 11 O 19-δ . The sequence of affection on catalytic activity of transition metal M for the topic reaction was NiCo>Fe> Mn> Cu.展开更多
A series of Ni modified hexaaluminates LaNi y Al 12- y O 19- δ ( y =0 3, 0 6, 0 9, 1 0) were prepared by decomposition of nitrates and calcination at high temperature. The crystalline structure and catalytic properti...A series of Ni modified hexaaluminates LaNi y Al 12- y O 19- δ ( y =0 3, 0 6, 0 9, 1 0) were prepared by decomposition of nitrates and calcination at high temperature. The crystalline structure and catalytic properties for CO 2 reforming of methane to synthesis gas were investigated by using XRD, XPS, TPR and TGA techniques. The results showed that a pure hexaaluminate LaNi y Al 12- y O 19- δ phase is formed only when y value is in 0< y ≤1. The reduced hexaaluminates LaNi y Al 12- y O 19- δ exhibit significant catalytic activity and stability for the reaction of CO 2 reforming of methane to synthesis gas at 780 ℃, and no deactivation resulting from carbon deposition is found. In the meantime, the catalytic activity is obviously affected by the modifier Ni in the hexaaluminate lattices. Under the same reaction conditions, the conversion of CH 4 and CO 2 increase with increase in the amount ( y value) of the modifier Ni.展开更多
The title coordination polymer,[Zn(Pyphen)(PZDC)(H2O)](1) (Pyphen=pyrazino[2,3-f][1,10]phen-anthroline and H2PZDC=pyrazine-2,3-dicarboxylic acid) has been obtained by using hydrothermal synthesis and characterized by ...The title coordination polymer,[Zn(Pyphen)(PZDC)(H2O)](1) (Pyphen=pyrazino[2,3-f][1,10]phen-anthroline and H2PZDC=pyrazine-2,3-dicarboxylic acid) has been obtained by using hydrothermal synthesis and characterized by elemental analysis,IR,TG,fluorescence spectrum and X-ray diffraction single-crystal structure analysis.The crystal is of triclinic,space group P1 with a=0.681 8(14) nm,b=0.743 9(15) nm,c=1.759 8(35) nm,α=94.329(30) °,β=95.514(30) °,γ=97.043(3) °,V=0.878 2(3) nm3,Z=2,Mr=481.73,Dc=1.822 g·cm-3,μ=1.452 mm-1,F(000) =448,Rint=0.033 9,R=0.042 5,wR=0.090 7.In complex 1,PZDC ligands link the Zn(Ⅱ) ions to form 1D chain structures,and further extended into a 3D supramolecular framework through π-π interactions and hydrogen bonding interactions.In addition,complex 1 exhibits strong photoluminescence at room temperature.CCDC:649569.展开更多
In this paper,the kinds and amount of carbon deposited over Ni base hexaaluminate LaNiAl 11 O 19 catalyst,after both CH 4 decomposition and CO 2 reforming of methane,was determined by means of X ray photoelectron spec...In this paper,the kinds and amount of carbon deposited over Ni base hexaaluminate LaNiAl 11 O 19 catalyst,after both CH 4 decomposition and CO 2 reforming of methane,was determined by means of X ray photoelectron spectroscopy (XPS) and thermogravimetric analysis(TGA) techniques,respectively.Over the catalyst,the rates of carbon deposited vs reaction time were also investigated during the reaction.Two carbon forms were produced,and graphitic carbon was the main and inactive carbon.展开更多
制备了一系列六铝酸盐 Sr MAl11O19δ催化剂。并通过 XRD、XPS、TPR和 TGA等实验技术对催化剂的结构和性能进行了表征。结果表明 ,这类物质的还原性和对二氧化碳重整甲烷制合成气反应催化活性与其结构和晶格中过渡金属 M的性质密切相关...制备了一系列六铝酸盐 Sr MAl11O19δ催化剂。并通过 XRD、XPS、TPR和 TGA等实验技术对催化剂的结构和性能进行了表征。结果表明 ,这类物质的还原性和对二氧化碳重整甲烷制合成气反应催化活性与其结构和晶格中过渡金属 M的性质密切相关。在 780℃反应 2 h,六铝酸盐 Sr Ni Al11O19δ表现出最高的催化活性和稳定性 ,CH4 和 CO2 转化率分别保持在 95 .0 %和 93 .4%以上 ,其它过渡金属 M取代六铝酸盐活性均低于Sr Ni Al11O19δ的活性。六铝酸盐晶格中过渡金属的活性顺序为 Ni Co>Fe>Mn>Cu。展开更多
文摘In this paper, a series of hexaaluminate oxides, LaMAl 11 O 19-δ (M=Fe, Co, Ni, Mn and Cu), were prepared using transition metals M to substitute Al in the hexaaluminate lattices. XRD analyses indicated that the series of hexaaluminates had almost the same magnetoplumbite crystal structure, however, they exhibted different reducibility and catalytic activities for CO 2 reforming of methane to synthesis gas. Among the LaMAl 11 O 19-δ samples, LaNiAl 11 O 19-δ showed the best catalytic activity for the reaction at 1 053 K for 2 h, the conversion of CH 4 and CO 2 was 98.8% and 97.6%, respectively, and the catalytic activities of rest Msubstituted catalysts were extremely lower than that of LaNiAl 11 O 19-δ . The sequence of affection on catalytic activity of transition metal M for the topic reaction was NiCo>Fe> Mn> Cu.
文摘A series of Ni modified hexaaluminates LaNi y Al 12- y O 19- δ ( y =0 3, 0 6, 0 9, 1 0) were prepared by decomposition of nitrates and calcination at high temperature. The crystalline structure and catalytic properties for CO 2 reforming of methane to synthesis gas were investigated by using XRD, XPS, TPR and TGA techniques. The results showed that a pure hexaaluminate LaNi y Al 12- y O 19- δ phase is formed only when y value is in 0< y ≤1. The reduced hexaaluminates LaNi y Al 12- y O 19- δ exhibit significant catalytic activity and stability for the reaction of CO 2 reforming of methane to synthesis gas at 780 ℃, and no deactivation resulting from carbon deposition is found. In the meantime, the catalytic activity is obviously affected by the modifier Ni in the hexaaluminate lattices. Under the same reaction conditions, the conversion of CH 4 and CO 2 increase with increase in the amount ( y value) of the modifier Ni.
文摘The title coordination polymer,[Zn(Pyphen)(PZDC)(H2O)](1) (Pyphen=pyrazino[2,3-f][1,10]phen-anthroline and H2PZDC=pyrazine-2,3-dicarboxylic acid) has been obtained by using hydrothermal synthesis and characterized by elemental analysis,IR,TG,fluorescence spectrum and X-ray diffraction single-crystal structure analysis.The crystal is of triclinic,space group P1 with a=0.681 8(14) nm,b=0.743 9(15) nm,c=1.759 8(35) nm,α=94.329(30) °,β=95.514(30) °,γ=97.043(3) °,V=0.878 2(3) nm3,Z=2,Mr=481.73,Dc=1.822 g·cm-3,μ=1.452 mm-1,F(000) =448,Rint=0.033 9,R=0.042 5,wR=0.090 7.In complex 1,PZDC ligands link the Zn(Ⅱ) ions to form 1D chain structures,and further extended into a 3D supramolecular framework through π-π interactions and hydrogen bonding interactions.In addition,complex 1 exhibits strong photoluminescence at room temperature.CCDC:649569.
文摘In this paper,the kinds and amount of carbon deposited over Ni base hexaaluminate LaNiAl 11 O 19 catalyst,after both CH 4 decomposition and CO 2 reforming of methane,was determined by means of X ray photoelectron spectroscopy (XPS) and thermogravimetric analysis(TGA) techniques,respectively.Over the catalyst,the rates of carbon deposited vs reaction time were also investigated during the reaction.Two carbon forms were produced,and graphitic carbon was the main and inactive carbon.
文摘制备了一系列六铝酸盐 Sr MAl11O19δ催化剂。并通过 XRD、XPS、TPR和 TGA等实验技术对催化剂的结构和性能进行了表征。结果表明 ,这类物质的还原性和对二氧化碳重整甲烷制合成气反应催化活性与其结构和晶格中过渡金属 M的性质密切相关。在 780℃反应 2 h,六铝酸盐 Sr Ni Al11O19δ表现出最高的催化活性和稳定性 ,CH4 和 CO2 转化率分别保持在 95 .0 %和 93 .4%以上 ,其它过渡金属 M取代六铝酸盐活性均低于Sr Ni Al11O19δ的活性。六铝酸盐晶格中过渡金属的活性顺序为 Ni Co>Fe>Mn>Cu。
