The LaCoO3 and 1%,10%,20%,30% doped Cu-LaCoO3 were prepared and studied. Two pretreated process were studied to investigate the effect of pretreating process of the catalysts on the reduction of SO2 by CO. One was usi...The LaCoO3 and 1%,10%,20%,30% doped Cu-LaCoO3 were prepared and studied. Two pretreated process were studied to investigate the effect of pretreating process of the catalysts on the reduction of SO2 by CO. One was using the mixture of SO2 and CO for catalysts sulfurized and poisoned in the presence of oxygen and the other was using SO2 and CO pre-reduced in the absence of oxygen. The evaluations were based on the SO2 conversion as well as sulfur selectivity and COS produced in a gradientless, quartz tubular packed-bed reactor. It was found that the catalysts sulfurized and poisoned under the mixture of SO2 and CO in the presence of oxygen could sustain its activity better than the pre-reduced catalysts. The activity decrease of the sulfurized and poisoned catalysts was very small after 4 h reaction. But for the two pre-reduced catalysts, SO2 conversion was only 17% over one 10% doped Cu-LaCoO3 and the other was deactivated after 140 min reaction. It was also found that all the doped Cu catalysts, sulfurized and poisoned in the presence of oxygen, presented higher oxygen resistance than the pre-reduced catalysts after reaction. The SO2 conversion of all the doped Cu catalysts decreased a little over 40 h reaction, while the activity of un-doped LaCoO3 was lowered to only 0.2 times of the initial activity. The other result showed that the COS formation was minimized in the doped Cu catalysts. From the results, it could be concluded that the 10% Cu-LaCoO3 was the most effective of the catalysts for removing sulfur with little COS formation.展开更多
The catalytic performance of sulfided Mn/Al 2O 3 and Cu-Mn/Al 2O 3 catalysts for the ammonia decomposition has been studied by using a fixed-bed flow apparatus. It is found that the addition of copper component to Mn/...The catalytic performance of sulfided Mn/Al 2O 3 and Cu-Mn/Al 2O 3 catalysts for the ammonia decomposition has been studied by using a fixed-bed flow apparatus. It is found that the addition of copper component to Mn/Al 2O 3 catalyst can increase its catalytic activity for ammonia decomposition. The results of TPR indicate that the existence of copper component significantly improves the reduction of catalysts, which is beneficial to form active metal sulfide phase to catalyze the reduction of SO 2 to H 2S by hydrogen. X-ray diffraction results reveal that the Cu-Mn/Al 2O 3 catalyst (n Cu /n Mn =0.4) contains a CuMn 2O 4 phase before reaction, and displays MnS peaks after reaction.展开更多
文摘The LaCoO3 and 1%,10%,20%,30% doped Cu-LaCoO3 were prepared and studied. Two pretreated process were studied to investigate the effect of pretreating process of the catalysts on the reduction of SO2 by CO. One was using the mixture of SO2 and CO for catalysts sulfurized and poisoned in the presence of oxygen and the other was using SO2 and CO pre-reduced in the absence of oxygen. The evaluations were based on the SO2 conversion as well as sulfur selectivity and COS produced in a gradientless, quartz tubular packed-bed reactor. It was found that the catalysts sulfurized and poisoned under the mixture of SO2 and CO in the presence of oxygen could sustain its activity better than the pre-reduced catalysts. The activity decrease of the sulfurized and poisoned catalysts was very small after 4 h reaction. But for the two pre-reduced catalysts, SO2 conversion was only 17% over one 10% doped Cu-LaCoO3 and the other was deactivated after 140 min reaction. It was also found that all the doped Cu catalysts, sulfurized and poisoned in the presence of oxygen, presented higher oxygen resistance than the pre-reduced catalysts after reaction. The SO2 conversion of all the doped Cu catalysts decreased a little over 40 h reaction, while the activity of un-doped LaCoO3 was lowered to only 0.2 times of the initial activity. The other result showed that the COS formation was minimized in the doped Cu catalysts. From the results, it could be concluded that the 10% Cu-LaCoO3 was the most effective of the catalysts for removing sulfur with little COS formation.
文摘The catalytic performance of sulfided Mn/Al 2O 3 and Cu-Mn/Al 2O 3 catalysts for the ammonia decomposition has been studied by using a fixed-bed flow apparatus. It is found that the addition of copper component to Mn/Al 2O 3 catalyst can increase its catalytic activity for ammonia decomposition. The results of TPR indicate that the existence of copper component significantly improves the reduction of catalysts, which is beneficial to form active metal sulfide phase to catalyze the reduction of SO 2 to H 2S by hydrogen. X-ray diffraction results reveal that the Cu-Mn/Al 2O 3 catalyst (n Cu /n Mn =0.4) contains a CuMn 2O 4 phase before reaction, and displays MnS peaks after reaction.
