Catalytic hydrodeoxygenation(HDO)of biomass-derived oxy-compounds to advanced hydrocarbon fuels usually requires bifunctional catalysts containing metals and acidic sites.The appropriate tuning of metal and/or acidic ...Catalytic hydrodeoxygenation(HDO)of biomass-derived oxy-compounds to advanced hydrocarbon fuels usually requires bifunctional catalysts containing metals and acidic sites.The appropriate tuning of metal and/or acidic active sites at interfaces of bifunctional catalysts can significantly improve catalyst activity and product selectivity.Here,4-trifuoromethyl salicylic acid(TFMSA),as a hydrothermal stable organic acid,was employed to tailor the bifunctional interface of Ru/γ-Al_(2)O_(3)to enhance the catalytic performance on converting lignin-derived phenols to jet fuel range cycloalkanes.More than 80%phenol was converted into cyclohexane at 230°C for 1 h over Ru/γ-Al_(2)O_(3)modified by TFMSA,which was about three times higher than that over unmodified Ru/γ-Al_(2)O_(3).X-ray diffraction(XRD),Transmission electron microscope(TEM),H2 chemisorption,and energy dispersive X-ray spectroscopy(EDS)elemental mapping results indicated that Ru nanoparticles and TFMSA were well distributed onγ-Al_(2)O_(3),and a nanoscale intimacy between Ru and TFMSA was reached.Meanwhile,Fourier transform infrared spectroscopy after pyridine adsorption(Py-FT-IR)analysis proved that Brønsted acidic sites on the catalytic interfaces of TFMSA modified Ru/γ-Al_(2)O_(3)had been improved.Moreover,the kinetic and density functional theory(DFT)results suggested that the synergistic effects of adjacent Ru nanoparticles and acidic sites were crutial for promoting the rate-limiting conversion step of phenol HDO to cyclohexane.展开更多
Plastic waste is causing serious environmental problems. Developing efficient, cheap and stable catalytic routes to convert plastic waste into valuable products is of great importance for sustainable development, but ...Plastic waste is causing serious environmental problems. Developing efficient, cheap and stable catalytic routes to convert plastic waste into valuable products is of great importance for sustainable development, but remains to be a challenging task. Zeolites are cheap and stable, but they are usually not efficient for plastic conversion at a low temperature. Herein a series of microporous and mesoporous zeolites were used to study the influence of porosity and acidity of zeolite on catalytic activity for plastics conversion. It was observed that H-Beta zeolite was an efficient catalyst for cracking high-density polyethylene to gasoline at 240℃, and the products were almost C_(4)–C_(12) alkanes. The effect of porosity and acidity on catalytic performance of zeolites was evaluated, which clearly visualized the good performance of H-Beta due to high surface area, large channel system, large amount accessible acidic sites. This study provides very useful information for designing zeolites for efficient conversion of plastics.展开更多
基金supported by the National Key R&D Program of China(2018YFB1501500)the 2115 Talent Development Program of China Agricultural University+3 种基金the National Natural Science Foundation of China(21903001)the Natural Science Foundation of Anhui Province(1908085QB58)the Chinese Universities Scientific Fund(2020TC116)the Research Innovation Fund for Graduate Students of CAU(2020XYZC05A)。
文摘Catalytic hydrodeoxygenation(HDO)of biomass-derived oxy-compounds to advanced hydrocarbon fuels usually requires bifunctional catalysts containing metals and acidic sites.The appropriate tuning of metal and/or acidic active sites at interfaces of bifunctional catalysts can significantly improve catalyst activity and product selectivity.Here,4-trifuoromethyl salicylic acid(TFMSA),as a hydrothermal stable organic acid,was employed to tailor the bifunctional interface of Ru/γ-Al_(2)O_(3)to enhance the catalytic performance on converting lignin-derived phenols to jet fuel range cycloalkanes.More than 80%phenol was converted into cyclohexane at 230°C for 1 h over Ru/γ-Al_(2)O_(3)modified by TFMSA,which was about three times higher than that over unmodified Ru/γ-Al_(2)O_(3).X-ray diffraction(XRD),Transmission electron microscope(TEM),H2 chemisorption,and energy dispersive X-ray spectroscopy(EDS)elemental mapping results indicated that Ru nanoparticles and TFMSA were well distributed onγ-Al_(2)O_(3),and a nanoscale intimacy between Ru and TFMSA was reached.Meanwhile,Fourier transform infrared spectroscopy after pyridine adsorption(Py-FT-IR)analysis proved that Brønsted acidic sites on the catalytic interfaces of TFMSA modified Ru/γ-Al_(2)O_(3)had been improved.Moreover,the kinetic and density functional theory(DFT)results suggested that the synergistic effects of adjacent Ru nanoparticles and acidic sites were crutial for promoting the rate-limiting conversion step of phenol HDO to cyclohexane.
基金the National Natural Science Foundation of China(Grant Nos.22293015,22293012,and 22121002)the Research Funds of Happiness Flower ECNU(2020ST2203).
文摘Plastic waste is causing serious environmental problems. Developing efficient, cheap and stable catalytic routes to convert plastic waste into valuable products is of great importance for sustainable development, but remains to be a challenging task. Zeolites are cheap and stable, but they are usually not efficient for plastic conversion at a low temperature. Herein a series of microporous and mesoporous zeolites were used to study the influence of porosity and acidity of zeolite on catalytic activity for plastics conversion. It was observed that H-Beta zeolite was an efficient catalyst for cracking high-density polyethylene to gasoline at 240℃, and the products were almost C_(4)–C_(12) alkanes. The effect of porosity and acidity on catalytic performance of zeolites was evaluated, which clearly visualized the good performance of H-Beta due to high surface area, large channel system, large amount accessible acidic sites. This study provides very useful information for designing zeolites for efficient conversion of plastics.