Quenching process and design of the quenching tower in acrylonitrile production in China were studied in order to decrease the polymerization loss of acrylonitrile in the quenching tower. Based on the research of acry...Quenching process and design of the quenching tower in acrylonitrile production in China were studied in order to decrease the polymerization loss of acrylonitrile in the quenching tower. Based on the research of acrylonitrile polymerization in the quenching tower, a new quenching process was proposed to avoid the disadvantages of the original process. Two kinds of internals were installed to improve the performance of the quenching tower. Through a series of air-flow and real-flow model experiments, the new quenching process and new design were showed to be successful in enhancing the mass and heat transfer in the vapor-liquid system and decreasing the loss of acrylonitrile.Industrial application showed satisfactory results of decrease of the acrylonitrile loss in the quenching tower by about 4.5% and increase of the acrylonitrile recovery of the whole plant by more than 4%.展开更多
The XYA-5 catalyst was first applied in commercial scale on an 80-kt/a acrylonitrile unit at the Daqing Refining and Chemical Company. Test results had shown that the once-through yield of acrylonitrile exceeded 80% w...The XYA-5 catalyst was first applied in commercial scale on an 80-kt/a acrylonitrile unit at the Daqing Refining and Chemical Company. Test results had shown that the once-through yield of acrylonitrile exceeded 80% with the unit consumption ofpropylene reaching 1032 kg on each ton of acrylonitrile. The product quality could be easily put under control and the distribution of reaction products was reasonable with good cleaning performance and stability of the catalyst that was suitable for use on this commercial unit.展开更多
The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and se...The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and security issues arising from the lithium metal anode.In addressing these issues,we propose a novel silicon-sulfurized poly(acrylonitrile)full battery.In this lithium metal-free system,the Li source is pre-loaded in the cathode,using a nitrogen evolution reaction(NER)to implant Li+into the silicon/carbon anode.Sulfurized poly(acrylonitrile)based on a solid–solid conversion mechanism can fundamentally circumvent the“shuttle effect”.Meanwhile,the silicon/carbon anode can achieve more efficient utiliza-tion and higher security when compared with the Li metal anode.The full cell used in this technology can deliver a capacity of 1169.3 mAh g^(-1),and it can be stabilized over 100 cycles,implying its excellent elec-trochemical stability.Furthermore,the practical pouch cell with a high sulfur loading of 4.2 mg cm^(-2)can achieve a high specific energy of 513.2 Wh kg-1.The mechanism of the NER in cathode has also been investigated and analyzed by in situ methods.Notably,this battery design completely conforms to the current battery production technology because of the degassing of gasbag,resulting in a low manufactur-ing cost.This work will open the avenue to develop a lithium metal-free battery using the NER.展开更多
文摘Quenching process and design of the quenching tower in acrylonitrile production in China were studied in order to decrease the polymerization loss of acrylonitrile in the quenching tower. Based on the research of acrylonitrile polymerization in the quenching tower, a new quenching process was proposed to avoid the disadvantages of the original process. Two kinds of internals were installed to improve the performance of the quenching tower. Through a series of air-flow and real-flow model experiments, the new quenching process and new design were showed to be successful in enhancing the mass and heat transfer in the vapor-liquid system and decreasing the loss of acrylonitrile.Industrial application showed satisfactory results of decrease of the acrylonitrile loss in the quenching tower by about 4.5% and increase of the acrylonitrile recovery of the whole plant by more than 4%.
文摘The XYA-5 catalyst was first applied in commercial scale on an 80-kt/a acrylonitrile unit at the Daqing Refining and Chemical Company. Test results had shown that the once-through yield of acrylonitrile exceeded 80% with the unit consumption ofpropylene reaching 1032 kg on each ton of acrylonitrile. The product quality could be easily put under control and the distribution of reaction products was reasonable with good cleaning performance and stability of the catalyst that was suitable for use on this commercial unit.
基金the National Natural Science Foundation of China(21922508,21673116,21633003,and U1801251)Natural Science Foundation of Jiangsu Province of China(BK20190009)and Key R&D Project funded by Department of Science and Technology of Jiangsu Province(BE2020003)。
文摘The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and security issues arising from the lithium metal anode.In addressing these issues,we propose a novel silicon-sulfurized poly(acrylonitrile)full battery.In this lithium metal-free system,the Li source is pre-loaded in the cathode,using a nitrogen evolution reaction(NER)to implant Li+into the silicon/carbon anode.Sulfurized poly(acrylonitrile)based on a solid–solid conversion mechanism can fundamentally circumvent the“shuttle effect”.Meanwhile,the silicon/carbon anode can achieve more efficient utiliza-tion and higher security when compared with the Li metal anode.The full cell used in this technology can deliver a capacity of 1169.3 mAh g^(-1),and it can be stabilized over 100 cycles,implying its excellent elec-trochemical stability.Furthermore,the practical pouch cell with a high sulfur loading of 4.2 mg cm^(-2)can achieve a high specific energy of 513.2 Wh kg-1.The mechanism of the NER in cathode has also been investigated and analyzed by in situ methods.Notably,this battery design completely conforms to the current battery production technology because of the degassing of gasbag,resulting in a low manufactur-ing cost.This work will open the avenue to develop a lithium metal-free battery using the NER.