Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,t...Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,the energy framework has undergone revolutionary changes.The energy attribute of petroleum will be gradually weakened,while the material and CO_(2)emission attributes will be gradually strengthened.Thus,the petrochemical processing basis,scientific concepts,and ideas will undergo major adjustments to reshape the petrochemical industry.Hence,it is necessary to reconsider the evolution of the petrochemical industry from a historical perspective and to clarify the historical causes,development contexts,and possible challenges in future development.Herein,we critically reassess the key drivers and rules guiding the development of the petrochemical industry and propose a reconstruction strategy based on simplified engineering thinking,innate nature of energy and material,and CO_(2)emissions,which can be realized through the integration of gasification with CO as the target product and recent C1 chemistry targeting the precise synthesis of chemicals.The concept of the petrochemical industry will change from the product-based process of selection and transformation of raw material molecules to the process of carbon atom reconfiguration driven by product CO_(2)emissions.More accurate management of C atoms can be accomplished with greatly improved utilization efficiency and the reduction of separation intensity and CO_(2)emissions via the stepwise introduction of a new approach in the current petrochemical industry.展开更多
HZSM-5,with good surface acidity and shape selectivity,was reported as hydrocarbon cracking catalyst for multiple decades,however the hydrothermal stability,especially dealumination of tetrahedrally coordinated framew...HZSM-5,with good surface acidity and shape selectivity,was reported as hydrocarbon cracking catalyst for multiple decades,however the hydrothermal stability,especially dealumination of tetrahedrally coordinated framework aluminum(TFAl),has been proved extensively as one of the major challenges during reactionregeneration process.Phosphorus was proposed to stabilize TFAl and indeed it enhanced the hydrothermal stability.Unfortunately,most of the phosphorus species would remain outside of the zeolite pore,mainly as polyphosphate species,and block the micropore severely,with only a limited portion introduced into the channel being able to interact with TFAl.Enlarging the pore size by alkali treatment(desilication)is one of the most convinced methods,but the details about specific P species during alkali treatment and its transformation upon hydrothermal activation is not acquired,thus the mechanism has not been fully understood.Herein,the P-containing species and its transformation during direct P modification and acid/alkali treatment followed by Pmodification have been studied,and the mechanism on the interaction between P and Al species has been investigated,using several analytical methods,especially Solid-state nuclear magnetic resonance(SSNMR)spectroscopy.It was found that the combination of desilication and subsequent phosphorus modification can enhance the activity of the ZSM-5 for the cracking of ethylcyclohexane,due to the better hydrothermal stabilization of acid sites by the enhanced interaction between phosphorus and TFAl,resulting from the improved accessibility of TFAl because of the successful generation of mesoporosity.Whereas the acid treatment followed by phosphorus modification,with declined retention of crystallinity and P/Al ratio,monoclinic/orthorhombic transition during steam activation,and the failed generation of mesopores,would cause obvious aggregation of the phosphorus species and could not improve the hydrothermal stability of the ZSM-5 effectively,and the direct phosphatation turned out much worse.Finally,a specific index that the intensity of the signal at 39 in 27Al MAS NMR spectra before steam activation was proposed as the indicator for determining the efficiency of phosphorus modification.And the proposed mechanism on the interaction between phosphorus and TFAl during the phosphorus modification could also be applicable in other zeolites.展开更多
Meso-Ni@HZSM-5 bi-functional catalysts were successfully post-encapsulated with about 3-7 nm Ni nanoparticles within HZSM-5 crystals,which exhibited significantly efficient conversion activity(67.4 g[palmitic acid]g[N...Meso-Ni@HZSM-5 bi-functional catalysts were successfully post-encapsulated with about 3-7 nm Ni nanoparticles within HZSM-5 crystals,which exhibited significantly efficient conversion activity(67.4 g[palmitic acid]g[Ni]^(−1)h^(−1))of palmitic acid and 100%selectivity of hydrocarbons with the outstanding stability during recycling application,compared to the impregnated Ni/HZSM-5 catalyst(14.0 g[palmitic acid]g[Ni]^(−1)h^(−1)).展开更多
文摘Petroleum has played a vital role as the major supplier of materials and energy during the evolution of human civilization.Given the change in demand for energy from high to low carbon and ultimately net zero carbon,the energy framework has undergone revolutionary changes.The energy attribute of petroleum will be gradually weakened,while the material and CO_(2)emission attributes will be gradually strengthened.Thus,the petrochemical processing basis,scientific concepts,and ideas will undergo major adjustments to reshape the petrochemical industry.Hence,it is necessary to reconsider the evolution of the petrochemical industry from a historical perspective and to clarify the historical causes,development contexts,and possible challenges in future development.Herein,we critically reassess the key drivers and rules guiding the development of the petrochemical industry and propose a reconstruction strategy based on simplified engineering thinking,innate nature of energy and material,and CO_(2)emissions,which can be realized through the integration of gasification with CO as the target product and recent C1 chemistry targeting the precise synthesis of chemicals.The concept of the petrochemical industry will change from the product-based process of selection and transformation of raw material molecules to the process of carbon atom reconfiguration driven by product CO_(2)emissions.More accurate management of C atoms can be accomplished with greatly improved utilization efficiency and the reduction of separation intensity and CO_(2)emissions via the stepwise introduction of a new approach in the current petrochemical industry.
文摘HZSM-5,with good surface acidity and shape selectivity,was reported as hydrocarbon cracking catalyst for multiple decades,however the hydrothermal stability,especially dealumination of tetrahedrally coordinated framework aluminum(TFAl),has been proved extensively as one of the major challenges during reactionregeneration process.Phosphorus was proposed to stabilize TFAl and indeed it enhanced the hydrothermal stability.Unfortunately,most of the phosphorus species would remain outside of the zeolite pore,mainly as polyphosphate species,and block the micropore severely,with only a limited portion introduced into the channel being able to interact with TFAl.Enlarging the pore size by alkali treatment(desilication)is one of the most convinced methods,but the details about specific P species during alkali treatment and its transformation upon hydrothermal activation is not acquired,thus the mechanism has not been fully understood.Herein,the P-containing species and its transformation during direct P modification and acid/alkali treatment followed by Pmodification have been studied,and the mechanism on the interaction between P and Al species has been investigated,using several analytical methods,especially Solid-state nuclear magnetic resonance(SSNMR)spectroscopy.It was found that the combination of desilication and subsequent phosphorus modification can enhance the activity of the ZSM-5 for the cracking of ethylcyclohexane,due to the better hydrothermal stabilization of acid sites by the enhanced interaction between phosphorus and TFAl,resulting from the improved accessibility of TFAl because of the successful generation of mesoporosity.Whereas the acid treatment followed by phosphorus modification,with declined retention of crystallinity and P/Al ratio,monoclinic/orthorhombic transition during steam activation,and the failed generation of mesopores,would cause obvious aggregation of the phosphorus species and could not improve the hydrothermal stability of the ZSM-5 effectively,and the direct phosphatation turned out much worse.Finally,a specific index that the intensity of the signal at 39 in 27Al MAS NMR spectra before steam activation was proposed as the indicator for determining the efficiency of phosphorus modification.And the proposed mechanism on the interaction between phosphorus and TFAl during the phosphorus modification could also be applicable in other zeolites.
基金financial supports from the Natural Science Foundation of China (No.21908225)the National Key Research and Development Program (No.2018YFC1801501)。
文摘Meso-Ni@HZSM-5 bi-functional catalysts were successfully post-encapsulated with about 3-7 nm Ni nanoparticles within HZSM-5 crystals,which exhibited significantly efficient conversion activity(67.4 g[palmitic acid]g[Ni]^(−1)h^(−1))of palmitic acid and 100%selectivity of hydrocarbons with the outstanding stability during recycling application,compared to the impregnated Ni/HZSM-5 catalyst(14.0 g[palmitic acid]g[Ni]^(−1)h^(−1)).
