A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roas...A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roasting temperature of 750℃ and roasting time of 30 min, molar ratio of Na2O to Al2O3 of 1.2, the leaching rates of alumina, vanadium and molybdenum in the spent catalyst are 97.2%, 95.8% and 98.9%, respectively. Vanadium and molybdenum in sodium aluminate solution can be recovered by precipitators A and B, and the precipitation rates of vanadium and molybdenum are 94.8% and 92.6%. Al(OH)3 was prepared from sodium aluminate solution in the carbonation decomposition process, and the purity of Al2O3 is 99.9% after calcination, the recovery of alumina reaches 90.6% in the whole process; the Ni-Co concentrate was leached by sulfuric acid, a nickel recovery of 98.2% and cobalt recovery over 98.5% can be obtained under the experimental condition of 30% H2SO4, 80℃, reaction time 4 h, mass ratio of liquid to solid 8, stirring rate 800r/min.展开更多
Amorphous Ni B/γ Al 2O 3 catalyst 1 is prepared with chemical reduction by KBH 4 solution after wetness impregnation and desiccation at 70 ℃ first and then at 110 ℃ for thorough water removal. Its higher catalytic ...Amorphous Ni B/γ Al 2O 3 catalyst 1 is prepared with chemical reduction by KBH 4 solution after wetness impregnation and desiccation at 70 ℃ first and then at 110 ℃ for thorough water removal. Its higher catalytic activity than amorphous Ni B/γ Al 2O 3 catalyst 2, prepared by conventional one step desiccation procedure at 110 ℃, is identified in liquid phase benzene hydrogenation to cyclohexane. Both catalysts are characterized by XRD and SEM, Ni B/γ Al 2O 3 catalyst 1 has a higher active specific surface area and dispersion degree, which can be assigned to more effective distribution of nickel salt over the support during desiccation, thus resulting in its superior activity in benzene hydrogenation.展开更多
Co-Ni/Al2O3catalyst was prepared by the fusion method and used in Fischer-Tropsch synthesis(FTS).The catalysts were characterized by means of nitrogen sorption and scanning electron microscopy.The effect of some react...Co-Ni/Al2O3catalyst was prepared by the fusion method and used in Fischer-Tropsch synthesis(FTS).The catalysts were characterized by means of nitrogen sorption and scanning electron microscopy.The effect of some reaction conditions such as temperature,pressure and H2/CO feed ratio on the catalytic performance of Co-Ni/Al2O3in CO hydrogenation was investigated in a fixed-bed reactor.The results indicate that the optimum reaction conditions are 250℃,0.3 MPa,H2/CO feed ratio of 2.0,and GHSV of 3 000 h-1.Kinetically,the reaction rate was correlated with the Langmuir-Hinshelwood-Hougen-Watson type models.The activation energy for the best fitted model is 88.41 kJ/mol,suggesting that the intra-particle mass transport is not significant.展开更多
基金Project(2003 UDBEA00C020) supported by the Collaborative Project of School and Province of Yunnan Province
文摘A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roasting temperature of 750℃ and roasting time of 30 min, molar ratio of Na2O to Al2O3 of 1.2, the leaching rates of alumina, vanadium and molybdenum in the spent catalyst are 97.2%, 95.8% and 98.9%, respectively. Vanadium and molybdenum in sodium aluminate solution can be recovered by precipitators A and B, and the precipitation rates of vanadium and molybdenum are 94.8% and 92.6%. Al(OH)3 was prepared from sodium aluminate solution in the carbonation decomposition process, and the purity of Al2O3 is 99.9% after calcination, the recovery of alumina reaches 90.6% in the whole process; the Ni-Co concentrate was leached by sulfuric acid, a nickel recovery of 98.2% and cobalt recovery over 98.5% can be obtained under the experimental condition of 30% H2SO4, 80℃, reaction time 4 h, mass ratio of liquid to solid 8, stirring rate 800r/min.
文摘Amorphous Ni B/γ Al 2O 3 catalyst 1 is prepared with chemical reduction by KBH 4 solution after wetness impregnation and desiccation at 70 ℃ first and then at 110 ℃ for thorough water removal. Its higher catalytic activity than amorphous Ni B/γ Al 2O 3 catalyst 2, prepared by conventional one step desiccation procedure at 110 ℃, is identified in liquid phase benzene hydrogenation to cyclohexane. Both catalysts are characterized by XRD and SEM, Ni B/γ Al 2O 3 catalyst 1 has a higher active specific surface area and dispersion degree, which can be assigned to more effective distribution of nickel salt over the support during desiccation, thus resulting in its superior activity in benzene hydrogenation.
文摘Co-Ni/Al2O3catalyst was prepared by the fusion method and used in Fischer-Tropsch synthesis(FTS).The catalysts were characterized by means of nitrogen sorption and scanning electron microscopy.The effect of some reaction conditions such as temperature,pressure and H2/CO feed ratio on the catalytic performance of Co-Ni/Al2O3in CO hydrogenation was investigated in a fixed-bed reactor.The results indicate that the optimum reaction conditions are 250℃,0.3 MPa,H2/CO feed ratio of 2.0,and GHSV of 3 000 h-1.Kinetically,the reaction rate was correlated with the Langmuir-Hinshelwood-Hougen-Watson type models.The activation energy for the best fitted model is 88.41 kJ/mol,suggesting that the intra-particle mass transport is not significant.