The selective hydrogenolysis of glycerol to 1,3-propanediol(1,3-PDO)is an attractive reaction due to the high demand for valorization of huge excess amounts of glycerol supply as well as the important application of 1...The selective hydrogenolysis of glycerol to 1,3-propanediol(1,3-PDO)is an attractive reaction due to the high demand for valorization of huge excess amounts of glycerol supply as well as the important application of 1,3-PDO in polyester industry.Nevertheless,the formation of 1,3-PDO is thermodynamically less favorable than 1,2-PDO,which necessitates the development of efficient catalysts to manipulate the reaction kinetics towards the 1,3-PDO formation.Among others,Pt-W based catalysts have shown promising activities and selectivities of 1,3-PDO although the reaction mechanism is not well addressed at the molecular level.In this short review,we have compared the performances of different Pt-W based catalysts and discussed the key factors influencing the activity and selectivity.Three possible reaction mechanisms have been discussed in terms of the synergy between Pt and WO_x and the origin of acid sites.Finally,the long-term stability of the Pt-W catalysts has been discussed.We hope this review will provide useful information for the development of more efficient catalysts for this important reaction.展开更多
CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxyge...CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxygen species and catalytic properties of CeO2 and Zr‐doped and Y‐doped ceria‐based materials are investigated in detail.Combining the observed catalytic performance with the characterization results,it can be deemed that surface lattice oxygen plays a critical role in methanethiol catalytic conversion over cerium oxides.Ce0.75Zr0.25O2 shows higher catalytic activity for CH3SH decomposition due to the large amount of surface lattice oxygen,readily available oxygen species,and excellent redox properties.Ce0.75Y0.25O2–δdisplays better catalytic stability owing to the greater number of oxygen vacancies that would promote bulk lattice oxygen migration to the surface of the catalyst in order to replenish surface lattice oxygen.In addition,the results show that the difference in chemical valence between Ce and the heteroatoms would strongly influence the amount of surface lattice oxygen as well as the mobility of bulk‐phase oxygen in these catalysts,thus affecting their activity and stability.展开更多
1-Decene was oligomerized over the supported AlCl3/γ-Al2O3 catalyst in a fixed-bed reactor. The effects of temperature and LHSV on oligomerization of 1-decene were investigated and the synthetic PAO was characterized...1-Decene was oligomerized over the supported AlCl3/γ-Al2O3 catalyst in a fixed-bed reactor. The effects of temperature and LHSV on oligomerization of 1-decene were investigated and the synthetic PAO was characterized with GC technique. Furthermore, the life of immobilized catalyst was tested and the mechanism of catalyst deactivation was discussed. The results showed that with an increasing temperature, the PAO yield increased and the kinematic viscosity of oil decreased. The GC results indicated that the synthesized PAO was a mixture consisting of dimers, trimers, tetramers and pentamers. The results of chloride content measurements and BET tests showed that catalyst deactivation could be mainly attributed to the loss of active components.展开更多
The oligomerzation reactions on different catalysts were investigated and discussed. 1-Octene, 1-decene, 1-do- decene, a mixture of olefins （with a mass ratio of w（l-octene）： w（1-decenc）：w（1-dodecene） equatin...The oligomerzation reactions on different catalysts were investigated and discussed. 1-Octene, 1-decene, 1-do- decene, a mixture of olefins （with a mass ratio of w（l-octene）： w（1-decenc）：w（1-dodecene） equating to 30：40：30）, and the products from paraffin cracking were oligomerized on the AlCl3/TiC14 catalyst. The results indicated that the AlCl3 catalyst led to severe coking reaction. With an increase in carbon number of alpha-olefins, the freezing point of oligomers increased and the kinematic viscosity decreased. The oligomers formed from the mixed olefins and the paraffin cracking products showed higher kinematic viscosity. Normal paraffins contained in the cracked products could increase the freezing point of oligomers. Furthermore, the distillation range of oligomers obtained from the cracked products was close to those of oligo- mers originated from 1-octene and 1-decene, while the oligomers obtained from the mixed olefins and 1-dodecene had simi- lar distillation ranges.展开更多
文摘The selective hydrogenolysis of glycerol to 1,3-propanediol(1,3-PDO)is an attractive reaction due to the high demand for valorization of huge excess amounts of glycerol supply as well as the important application of 1,3-PDO in polyester industry.Nevertheless,the formation of 1,3-PDO is thermodynamically less favorable than 1,2-PDO,which necessitates the development of efficient catalysts to manipulate the reaction kinetics towards the 1,3-PDO formation.Among others,Pt-W based catalysts have shown promising activities and selectivities of 1,3-PDO although the reaction mechanism is not well addressed at the molecular level.In this short review,we have compared the performances of different Pt-W based catalysts and discussed the key factors influencing the activity and selectivity.Three possible reaction mechanisms have been discussed in terms of the synergy between Pt and WO_x and the origin of acid sites.Finally,the long-term stability of the Pt-W catalysts has been discussed.We hope this review will provide useful information for the development of more efficient catalysts for this important reaction.
基金supported by the National Natural Science Foundation of China (21667016, 21267011, U1402233)~~
文摘CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxygen species and catalytic properties of CeO2 and Zr‐doped and Y‐doped ceria‐based materials are investigated in detail.Combining the observed catalytic performance with the characterization results,it can be deemed that surface lattice oxygen plays a critical role in methanethiol catalytic conversion over cerium oxides.Ce0.75Zr0.25O2 shows higher catalytic activity for CH3SH decomposition due to the large amount of surface lattice oxygen,readily available oxygen species,and excellent redox properties.Ce0.75Y0.25O2–δdisplays better catalytic stability owing to the greater number of oxygen vacancies that would promote bulk lattice oxygen migration to the surface of the catalyst in order to replenish surface lattice oxygen.In addition,the results show that the difference in chemical valence between Ce and the heteroatoms would strongly influence the amount of surface lattice oxygen as well as the mobility of bulk‐phase oxygen in these catalysts,thus affecting their activity and stability.
基金the SINOPEC Corporation for the financial support
文摘1-Decene was oligomerized over the supported AlCl3/γ-Al2O3 catalyst in a fixed-bed reactor. The effects of temperature and LHSV on oligomerization of 1-decene were investigated and the synthetic PAO was characterized with GC technique. Furthermore, the life of immobilized catalyst was tested and the mechanism of catalyst deactivation was discussed. The results showed that with an increasing temperature, the PAO yield increased and the kinematic viscosity of oil decreased. The GC results indicated that the synthesized PAO was a mixture consisting of dimers, trimers, tetramers and pentamers. The results of chloride content measurements and BET tests showed that catalyst deactivation could be mainly attributed to the loss of active components.
基金the SINOPEC Corporation for the financial support
文摘The oligomerzation reactions on different catalysts were investigated and discussed. 1-Octene, 1-decene, 1-do- decene, a mixture of olefins （with a mass ratio of w（l-octene）： w（1-decenc）：w（1-dodecene） equating to 30：40：30）, and the products from paraffin cracking were oligomerized on the AlCl3/TiC14 catalyst. The results indicated that the AlCl3 catalyst led to severe coking reaction. With an increase in carbon number of alpha-olefins, the freezing point of oligomers increased and the kinematic viscosity decreased. The oligomers formed from the mixed olefins and the paraffin cracking products showed higher kinematic viscosity. Normal paraffins contained in the cracked products could increase the freezing point of oligomers. Furthermore, the distillation range of oligomers obtained from the cracked products was close to those of oligo- mers originated from 1-octene and 1-decene, while the oligomers obtained from the mixed olefins and 1-dodecene had simi- lar distillation ranges.
基金supported by Climate Change Response Project (NRF-2019M1A2A2065612)Brainlink Project (NRF-2022H1D3A3A01081140) funded by the Ministry of Science and ICT of Korea via National Research Foundation+1 种基金by research funds from Hanhwa Solutions Chemicals (2.220990.01) and UNIST (1.190013.01)supported by the Institute for Basic Science (IBS-R019-D1)。
