Dehydrogenation of propane(PDH)technology is one of the most promising on-purpose technologies to solve supply-demand unbalance of propylene.The industrial catalysts for PDH,such as Pt-and Cr-based catalysts,still hav...Dehydrogenation of propane(PDH)technology is one of the most promising on-purpose technologies to solve supply-demand unbalance of propylene.The industrial catalysts for PDH,such as Pt-and Cr-based catalysts,still have their own limitation in expensive price and security issues.Thus,a deep understanding into the structure-performance relationship of the catalysts during PDH reaction is necessary to achieve innovation in advanced high-efficient catalysts.In this review,we focused on discussion of structure-performance relationship of catalysts in PDH.Based on analysis of reaction mechanism and nature of active sites,we detailed interaction mechanism between structure of active sites and catalytic performance in metal catalysts and oxide catalysts.The relationship between coke deposition,co-feeding gas,catalytic activity and nanostructure of the catalysts are also highlighted.With these discussions on the relationship between structure and performances,we try to provide the insights into microstructure of active sites in PDH and the rational guidance for future design and development of PDH catalysts.展开更多
The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the cata...The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the catalyst life.However, it is still necessary to develop novel catalysts with robust stability. Herein, the phosphorus-modified carbon nanotube-supported Pt nanoparticles were employed for the PDH process. Phosphorus modification improves the Pt dispersion, effectively promoting the activity of Pt/P-CNTs. Additionally, the phosphorus-modified CNTs can interact strongly with Pt nanoparticles by improving the electron transfer or hybridization, stabilizing Pt nanoparticles from agglomeration, and significantly enhancing the catalyst stability.展开更多
Several Pt-θ-Al_2O_3 catalysts with similar ultra-low Cl contents were used to investigate the influence of dechlorination temperature on propane dehydrogenation reaction. The Pt-θ-Al_2O_3 catalyst treated at a high...Several Pt-θ-Al_2O_3 catalysts with similar ultra-low Cl contents were used to investigate the influence of dechlorination temperature on propane dehydrogenation reaction. The Pt-θ-Al_2O_3 catalyst treated at a highest dechlorination temperature showed a lowest propane rate and propylene selectivity. The scanning transmission electron microscopy showed that the dispersions of Pt nanoparticles decreased with an increasing dechlorination temperature. The temperature-programmed reduction analysis showed that higher dechlorination temperature could lead to strong interactions between the metal and support, making it difficult to reduce Pt nanoparticles. The temperature-programmed oxidation analysis implied that more coke was deposited on the metal for catalyst treated at higher dechlorination temperature. The Raman spectra and the H/C ratio showed that more side-reactions, such as cracking and severe deep dehydrogenation reactions, occurred on catalysts treated at higher dechlorination temperatures. Therefore, the lower the dispersion of Pt nanoparticles was, the stronger the metal-support interactions and increased side-reactions would be, resulting in lower catalytic activity for Pt-θ-Al_2O_3 treated with higher dechlorination temperature.展开更多
SBA-15 and HMS supported chromia catalysts were prepared and characterized. Chromia is highly dispersed on the mesoporous supports when its loading is 7 wt%. The supported catalysts display high activity, selectivity ...SBA-15 and HMS supported chromia catalysts were prepared and characterized. Chromia is highly dispersed on the mesoporous supports when its loading is 7 wt%. The supported catalysts display high activity, selectivity and stability for dehydrogenation of ethylbenzene and propane. ESR measurement of the catalysts before and after reaction shows that the active species for dehydrogenation reaction might be Cr3+ species on the catalyst surface, and the activity of the catalyst is probably correlated with the dispersion of Cr3+ species.展开更多
通过在载体SiO_(2)或Al_(2)O_(3)上添加金属氧化物,制备了Pt-La GaO_(3)/SiO_(2)、Pt-La GaO_(3)/Al_(2)O_(3)、Pt-La Al O_(3)/SiO_(2)、Pt-La_(2)O_(3)/SiO_(2)、Pt-Ga_(2)O_(3)/SiO_(2)系列Pt基催化剂,探索金属氧化物的修饰对Pt活性...通过在载体SiO_(2)或Al_(2)O_(3)上添加金属氧化物,制备了Pt-La GaO_(3)/SiO_(2)、Pt-La GaO_(3)/Al_(2)O_(3)、Pt-La Al O_(3)/SiO_(2)、Pt-La_(2)O_(3)/SiO_(2)、Pt-Ga_(2)O_(3)/SiO_(2)系列Pt基催化剂,探索金属氧化物的修饰对Pt活性中心丙烷脱氢性能的影响。实验结果表明,使用具有适宜组成和结构的复合金属氧化物修饰Pt催化剂,可以极大提高催化剂的丙烷脱氢性能。展开更多
基金supported by the National Natural Science Foundation of China(21872163,21972166)National Engineering Laboratory for Mobile Source Emission Control Technology(NELMS2017A05)+1 种基金Beijing Natural Science Foundation(2202045,2182060)PetroChina Innovation Foundation(2018D-5007-0505)
文摘Dehydrogenation of propane(PDH)technology is one of the most promising on-purpose technologies to solve supply-demand unbalance of propylene.The industrial catalysts for PDH,such as Pt-and Cr-based catalysts,still have their own limitation in expensive price and security issues.Thus,a deep understanding into the structure-performance relationship of the catalysts during PDH reaction is necessary to achieve innovation in advanced high-efficient catalysts.In this review,we focused on discussion of structure-performance relationship of catalysts in PDH.Based on analysis of reaction mechanism and nature of active sites,we detailed interaction mechanism between structure of active sites and catalytic performance in metal catalysts and oxide catalysts.The relationship between coke deposition,co-feeding gas,catalytic activity and nanostructure of the catalysts are also highlighted.With these discussions on the relationship between structure and performances,we try to provide the insights into microstructure of active sites in PDH and the rational guidance for future design and development of PDH catalysts.
基金supported by the National Natural Science Foundation of China (Grant 21706036)the State Key Laboratory of Catalytic Materials and Reaction Engineering (RIPP, SINOPEC)the Natural Science Foundation of Fujian Province (Grant 2018J05019)
文摘The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the catalyst life.However, it is still necessary to develop novel catalysts with robust stability. Herein, the phosphorus-modified carbon nanotube-supported Pt nanoparticles were employed for the PDH process. Phosphorus modification improves the Pt dispersion, effectively promoting the activity of Pt/P-CNTs. Additionally, the phosphorus-modified CNTs can interact strongly with Pt nanoparticles by improving the electron transfer or hybridization, stabilizing Pt nanoparticles from agglomeration, and significantly enhancing the catalyst stability.
基金financially supported by grants from the State Key Laboratory of Catalytic Materials and Reaction Engineering (RIPP, SINOPEC)the National Natural Science Foundation of China (Grant No. 21706036)+2 种基金the Natural Science Foundation of Fujian Province (Grant No. 2018J05019)the Fujian Educational Bureau (Grant No. JAT170073)the Talent Foundation of Fuzhou University (Grant No. XRC-1650)
文摘Several Pt-θ-Al_2O_3 catalysts with similar ultra-low Cl contents were used to investigate the influence of dechlorination temperature on propane dehydrogenation reaction. The Pt-θ-Al_2O_3 catalyst treated at a highest dechlorination temperature showed a lowest propane rate and propylene selectivity. The scanning transmission electron microscopy showed that the dispersions of Pt nanoparticles decreased with an increasing dechlorination temperature. The temperature-programmed reduction analysis showed that higher dechlorination temperature could lead to strong interactions between the metal and support, making it difficult to reduce Pt nanoparticles. The temperature-programmed oxidation analysis implied that more coke was deposited on the metal for catalyst treated at higher dechlorination temperature. The Raman spectra and the H/C ratio showed that more side-reactions, such as cracking and severe deep dehydrogenation reactions, occurred on catalysts treated at higher dechlorination temperatures. Therefore, the lower the dispersion of Pt nanoparticles was, the stronger the metal-support interactions and increased side-reactions would be, resulting in lower catalytic activity for Pt-θ-Al_2O_3 treated with higher dechlorination temperature.
文摘SBA-15 and HMS supported chromia catalysts were prepared and characterized. Chromia is highly dispersed on the mesoporous supports when its loading is 7 wt%. The supported catalysts display high activity, selectivity and stability for dehydrogenation of ethylbenzene and propane. ESR measurement of the catalysts before and after reaction shows that the active species for dehydrogenation reaction might be Cr3+ species on the catalyst surface, and the activity of the catalyst is probably correlated with the dispersion of Cr3+ species.
文摘通过在载体SiO_(2)或Al_(2)O_(3)上添加金属氧化物,制备了Pt-La GaO_(3)/SiO_(2)、Pt-La GaO_(3)/Al_(2)O_(3)、Pt-La Al O_(3)/SiO_(2)、Pt-La_(2)O_(3)/SiO_(2)、Pt-Ga_(2)O_(3)/SiO_(2)系列Pt基催化剂,探索金属氧化物的修饰对Pt活性中心丙烷脱氢性能的影响。实验结果表明,使用具有适宜组成和结构的复合金属氧化物修饰Pt催化剂,可以极大提高催化剂的丙烷脱氢性能。
