Catalytic upgrading of bio-ethanol to 1,3-butadiene(1,3-BD,ETB)is a renewable and low-carbon technology for the bulk chemical production.Exploring robust catalysts and getting in-depth understanding of the relationshi...Catalytic upgrading of bio-ethanol to 1,3-butadiene(1,3-BD,ETB)is a renewable and low-carbon technology for the bulk chemical production.Exploring robust catalysts and getting in-depth understanding of the relationship between the structure of catalytic sites and reaction selectivity are of great significance for ETB process applications.In this study,we constructed a robust Cu-Zr/SiO_(2) catalyst by an ammonia evaporation and post-impregnation method.Over the optimal 2%Cu-8%Zr/SiO_(2) catalyst,superior performance of 69.6%1,3-BD selectivity and 71.2%ethanol conversion were obtained.Systematic characterizations revealed that three types of Cu-Zr-Si active sites were probably constructed on the Cu-8%Zr/SiO_(2) catalysts as varying the Cu loadings from 0.5 to 20%,affording greatly different activity and selectivity in the ETB process.The 1,3-BD productivity over the(SiO)_(2)(CuO)Zr-OH sites was 8.2 and 77.2 times higher than that of(CuO)_(2)-Zr-(OSi)2 and Cu-(O)_(2)-Zr-(OSi)2 sites,respectively,attributed to the high activities and good balance among the reactions of dehydrogenation,aldol condensation,and MPVO reduction.展开更多
The effect of thermomechanical treatments on the microstructures and properties of Cu-2.1Ni-0.5Si- 0.2Zr alloy was investigated. The hot-rolled plates were solution treated at 920 ℃ for 1.5 h, quenched into water, co...The effect of thermomechanical treatments on the microstructures and properties of Cu-2.1Ni-0.5Si- 0.2Zr alloy was investigated. The hot-rolled plates were solution treated at 920 ℃ for 1.5 h, quenched into water, cold rolled by 70 % reduction in thickness, and then aged at 400, 450 and 500 ℃for various times. The variation in tensile strength and electrical conductivity of the alloy was measured as a function of the aging time. The results show the peak strength value of 665 MPa for the alloy aged at 450 ℃ for 2 h. However, the electrical conductivity is observed to reach a maximum of 47 % IACS aged at 450℃for 8 h. OM, SEM, and TEM were used for microstructural inspection of the alloy. Precipitation occurs preferentially at deformation bands in the cold-rolled alloy. Properties behavior is discussed in the light of microstructural features.展开更多
In this article, a novel Al-6Zr-2P master alloy with ZrP particles was successfully synthesized, and the refining performance of this novel master alloy for the primary Si in Cu-50Si alloys was also investigated. By m...In this article, a novel Al-6Zr-2P master alloy with ZrP particles was successfully synthesized, and the refining performance of this novel master alloy for the primary Si in Cu-50Si alloys was also investigated. By means of the fracture plane observation, it is found that the ZrP phase would precipitate first in the solidification pro- cess, and then, the ZrAl3 phase grows around them. Fur- thermore, it is observed that the refining effect can be remarkably improved by changing the addition sequence of the raw materials. After the melting of commercial Cu, the 2.0 wt% Al-6Zr-2P master alloy and crystalline Si were added in sequence, and the mean size of the primary Si in Cu-50Si alloy can be significantly refined from 255.7 to 75.3 gm. Meanwhile, the refining mechanism was dis- cussed in detail.展开更多
基金supported by the National Natural Science Foundation of China(21721004,22108274)“Transformational Technologies for Clean Energy and Demonstration”Strategic Priority Research Program of the Chinese Academy of Sciences(XDA 21060200).
文摘Catalytic upgrading of bio-ethanol to 1,3-butadiene(1,3-BD,ETB)is a renewable and low-carbon technology for the bulk chemical production.Exploring robust catalysts and getting in-depth understanding of the relationship between the structure of catalytic sites and reaction selectivity are of great significance for ETB process applications.In this study,we constructed a robust Cu-Zr/SiO_(2) catalyst by an ammonia evaporation and post-impregnation method.Over the optimal 2%Cu-8%Zr/SiO_(2) catalyst,superior performance of 69.6%1,3-BD selectivity and 71.2%ethanol conversion were obtained.Systematic characterizations revealed that three types of Cu-Zr-Si active sites were probably constructed on the Cu-8%Zr/SiO_(2) catalysts as varying the Cu loadings from 0.5 to 20%,affording greatly different activity and selectivity in the ETB process.The 1,3-BD productivity over the(SiO)_(2)(CuO)Zr-OH sites was 8.2 and 77.2 times higher than that of(CuO)_(2)-Zr-(OSi)2 and Cu-(O)_(2)-Zr-(OSi)2 sites,respectively,attributed to the high activities and good balance among the reactions of dehydrogenation,aldol condensation,and MPVO reduction.
基金supported by the Project of National "863"Foundation of China(No.2006AA03Z522)Science and Technology of Beijing(No.10231103)
文摘The effect of thermomechanical treatments on the microstructures and properties of Cu-2.1Ni-0.5Si- 0.2Zr alloy was investigated. The hot-rolled plates were solution treated at 920 ℃ for 1.5 h, quenched into water, cold rolled by 70 % reduction in thickness, and then aged at 400, 450 and 500 ℃for various times. The variation in tensile strength and electrical conductivity of the alloy was measured as a function of the aging time. The results show the peak strength value of 665 MPa for the alloy aged at 450 ℃ for 2 h. However, the electrical conductivity is observed to reach a maximum of 47 % IACS aged at 450℃for 8 h. OM, SEM, and TEM were used for microstructural inspection of the alloy. Precipitation occurs preferentially at deformation bands in the cold-rolled alloy. Properties behavior is discussed in the light of microstructural features.
基金financially supported by the National Natural Science Foundation of China (No. 51202088)the Shandong Doctoral Foundation (BS2010CL005)+1 种基金the Doctoral Foundation (No. XBS1106)the Research Foundation of the University of Jinan (No. XKY1106)
文摘In this article, a novel Al-6Zr-2P master alloy with ZrP particles was successfully synthesized, and the refining performance of this novel master alloy for the primary Si in Cu-50Si alloys was also investigated. By means of the fracture plane observation, it is found that the ZrP phase would precipitate first in the solidification pro- cess, and then, the ZrAl3 phase grows around them. Fur- thermore, it is observed that the refining effect can be remarkably improved by changing the addition sequence of the raw materials. After the melting of commercial Cu, the 2.0 wt% Al-6Zr-2P master alloy and crystalline Si were added in sequence, and the mean size of the primary Si in Cu-50Si alloy can be significantly refined from 255.7 to 75.3 gm. Meanwhile, the refining mechanism was dis- cussed in detail.
