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
In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in thi...In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in this ionic liquids class.The chemical structure of this EIL was rigorously characterized and confirmed using FTIR spectroscopy,1D,and 2D-NMR analyses.The thermal behavior assessment was conducted through DSC and TGA experiments.DSC analysis revealed an endothermic glass transition at T_(g)=-61℃,followed by an exothermic degradation event at T_(onset)=311℃.Similarly,TGA thermograms exhibited a one-stage decomposition process resulting in 100% mass loss of the sample.Furthermore,the short-term thermal stability of the azide EIL was investigated by combining the non-isothermal TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic approaches.Consequently,the Arrhenius parameters(E_(a)=154 kJ·mol^(-1),Log(A/s^(-1))=11.8) and the most probable reaction model g(a) were determined.The observed high decomposition temperatures and the significantly elevated activation energy affirm the enhanced thermal stability of the modified EIL.These findings revealed that[BBIm][N_(3)]EIL can be a promising candidate for advanced energetic material application.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.
文摘In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in this ionic liquids class.The chemical structure of this EIL was rigorously characterized and confirmed using FTIR spectroscopy,1D,and 2D-NMR analyses.The thermal behavior assessment was conducted through DSC and TGA experiments.DSC analysis revealed an endothermic glass transition at T_(g)=-61℃,followed by an exothermic degradation event at T_(onset)=311℃.Similarly,TGA thermograms exhibited a one-stage decomposition process resulting in 100% mass loss of the sample.Furthermore,the short-term thermal stability of the azide EIL was investigated by combining the non-isothermal TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic approaches.Consequently,the Arrhenius parameters(E_(a)=154 kJ·mol^(-1),Log(A/s^(-1))=11.8) and the most probable reaction model g(a) were determined.The observed high decomposition temperatures and the significantly elevated activation energy affirm the enhanced thermal stability of the modified EIL.These findings revealed that[BBIm][N_(3)]EIL can be a promising candidate for advanced energetic material application.
