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Review of Iron-Based Catalysts for Carbon Dioxide Fischer-Tropsch Synthesis

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Transactions of Tianjin University 2024年第2期30卷 178-197页

作者： Ji-Yue Jia Yu-Ling Shan Yong-Xiao Tuo Hao Yan Xiang Feng De Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Department of Chemical Engineering Norwegian University of Science and Technology7491 TrondheimNorway

Capturing and utilizing CO_(2)from the production process is the key to solving the excessive CO_(2)emission problem. CO_(2)hydrogenation with green hydrogen to produce olefins is an effective and promising way to utilize CO_(2)and produce valuable chemicals. The olefins can be produced by CO_(2)hydrogenation through two routes, i.e., CO_(2)-FTS (carbon dioxide Fischer- Tropsch synthesis) and MeOH (methanol-mediated), among which CO_(2)-FTS has significant advantages over MeOH in practical applications due to its relatively high CO_(2)conversion and low energy consumption potentials. However, the CO_(2)-FTS faces challenges of difficult CO_(2)activation and low olefins selectivity. Iron-based catalysts are promising for CO_(2)-FTS due to their dual functionality of catalyzing RWGS and CO-FTS reactions. This review summarizes the recent progress on iron-based catalysts for CO_(2)hydrogenation via the FTS route and analyzes the catalyst optimization from the perspectives of additives, active sites, and reaction mechanisms. Furthermore, we also outline principles and challenges for rational design of high-performance CO_(2)-FTS catalysts.

关键词： CO_(2)hydrogenation olefins CO_(2)-FTS Iron-based catalysts

Cross-metathesis of biomass to olefins:Molecular catalysis bridging the gap between fossil and bio-energy

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Chinese Journal of Chemical Engineering 2022年第8期35卷 44-60页

作者： Wenjuan Yan Zhenchao You Kexin Meng Feng Du Shuxia Zhang Xin Jin State Key Laboratory of Heavy Oil Processing Center for Chemical Engineering Experimental TeachingChina University of PetroleumQingdao 266580China

Terminal olefins are important building blocks for the industry of biofuels,oligomers,and lubricants production.The industrial processes for production of olefins involving oligomerization of ethylene or cracking of petrochemical waxes have several flaws including low yield and high cost in product separation.Cross-metathesis of bio-derived unsaturated fatty esters and olefins with ethylene(ethenolysis),allows the conversion of sustainable waste biomass to various renewable olefins with much safer,less toxic,sustainable,and zero-CO_(2) emission processes.To our best knowledge,however,a comprehensive summary of key advances in this field(since 2017)is yet to be available,particularly on molecular features of homogeneous and heterogeneous catalysts.This paper presents a critical review on molecular structures of metal complex and oxide catalysts for ethenolysis of olefins and oleochemicals.The influence of cationic centers,coordination conditions,nature of ligands,operating conditions on catalyst performances will be systematically discussed along with relevant reaction mechanism.The key challenges for rational design of coordinated cationic hybrids have been summarized,which will provide insights to technological advancement of large-scale production of oleochemical-derived olefins.

关键词： Metathesis Catalysts Metal complex Metal oxide olefins Oleochemicals

Advances in Electrochemical Oxidation of olefins to Epoxides

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CCS Chemistry 2023年第5期5卷 1028-1042页

作者： Peng Zhang Tuo Wang Jinlong Gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072 Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072 National Industry-Education Platform of Energy Storage Tianjin UniversityTianjin 300350 Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192 Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207Fujian

Epoxides are important chemicals and used in multiple fields.The conventional thermal-catalytic production of epoxides consumes a large amount of energy and generates abundant carbon emissions.Therefore,sustainable manufacturing technologies are highly desired.Taking advantage of renewable electricity to drive electrochemical epoxidation reactions provides a novel approach to generating value-added products in the chemicals sector.This review describes the current progress of selective electrochemical oxidation of olefins to epoxides,which is categorized according to the different reaction mechanisms.The halide-mediated method is first discussed,followed by an overview of electrochemical epoxidations with H_(2)O and O_(2)-derived H_(2)O_(2).Moreover,the existing problems in this fast-growing field and future developing directions are pointed out.This review hopes to provide inspiration for the design of electrocatalysts,electrode materials,and electrolyzers for the electrochemical production of epoxides in a sustainable manner.

关键词： electrochemistry selective oxidation olefins epoxides power-to-X

Conversion of Carbonyl Compounds to olefins via Enolate Intermediate

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Chinese Journal of Chemistry 2019年第8期37卷 781-785页

作者： Zhi-Chao Cao Pei-Lin Xu Qin-Yu Luo Xiao-Lei Li Da-Gang Yu Huayi Fang Zhang-Jie Shi Department of Chemistry Fudan UniversityShanghai 200433China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China College of Chemistry Sichuan UniversityChengduSichuan 610064China

Summary of main observation and conclusion A general and efficient protocol to synthesize substituted olefins from carbonyl compounds via nickel catalyzed C-O activation of enolates was developed.Besides ketones,aldehydes were also suitable substrates for the presented catalytic system to produce di-or tri-substituted olefins.It is worth noting that this approach exhibited good tolerance to highly reactive tertiary alcohols,which could not survive in other reported routes for converting carbonyl compounds to olefins.This method also showed good regio-and stereo-selectivity for olefin products.Preliminary mechanistic studies indicated that the reaction was accomplished through nickel catalyzed C-O activation of enolates,thus offering helpful contribution to current enol chemistry.

关键词： Carbonyl Compounds olefins Enolate Intermediate

Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and Switchable Domino Reactions of a-Substituted Activated olefins with Formaldehyde and Mechanism Elucidation

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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing Gu Ben-Xian Xiao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction Switchable Domino Reactions of a-Substituted Activated olefins Formaldehyde Mechanism Elucidation

Methylcyclopentenyl cation mediated reaction route in methanol-to-olefins reaction over H-RUB-50 with small cavity

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Journal of Energy Chemistry 2020年第6期29卷 25-30,I0002页

作者： Wenna Zhang Shutao Xu Yuchun Zhi Yingxu Wei Zhongmin Liu National Engineering Laboratory for Methanol to olefins State Energy Low Carbon Catalysis and Engineering R&D CenterDalian National Laboratory for Clean EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Methylcyclopentenyl cations(MCP+)have been regarded as active intermediates during methanol conversion,however,their function mode in the reaction are still uncertain.In our recent report,trimethylcyclopentenyl cation(triMCP+)and its deprotonated counterpart(trimethylcyclopentadiene,tri MCP)were directly captured on H-RUB-50 catalyst with small cavity by the aid of in situ 13C MAS NMR spectroscopy,and their higher catalytic reactivity were clarified by 12C/13C-CH3OH isotopic switch experiment.In this contribution,an alternative route-cyclopentadienes-based cycle was applied on methanol conversion catalyzed on the H-RUB-50,in which ethene was produced with the participation of tri MCP+as critical intermediate.Then the cyclopentadienes-based cycle was predicted to be energetically favorable for ethene formation by density functional theory(DFT)calculations.The energetic comparison of paring mechanism in the aromatics-based cycle and cyclopentadienes-based cycle with the involvements of trimethylcyclopentadienyl(tri MCPdi+)and tri MCP+as the corresponding active intermediates suggests that cyclopentadienes-based cycle is a feasible route for ethene formation.Furthermore,this work highlights the importance of the steric constraint and the host-guest interaction induced by the zeolite with cavity structure in the formation of intermediates and reaction pathway.

关键词： Methanol to olefins H-RUB-50 Methylcyclopentenyl cation Cyclopentadienes-based cycle

Iron-based Fischer–Tropsch synthesis of lower olefins: The nature of χ-Fe_5C_2 catalyst and why and how to introduce promoters

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Journal of Energy Chemistry 2016年第6期25卷 911-916页

作者： Di Wang Bingxu Chen Xuezhi Duan De Chen Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology Department of Chemical Engineering Norwegian University of Science and Technology

As a sustainable and short-flow process, iron-catalyzed direct conversion of CO-rich syngas to lower olefins without intermediate steps, i.e., Fischer–Tropsch-to-olefins (FTO), has received increasing attention. However, its fundamental understanding is usually limited by the complex crystal phase composition in addition to the interferences of the promoter effects and inevitable catalyst deactivation. Until recently, the combination of multiple in-situ/ex-situ characterizations and theoretical studies has evidenced H?gg iron carbide (χ-Fe5C2) as the dominant active phase of iron-based Fischer–Tropsch catalysts. This perspective attempts to review and discuss some recent progresses on the nature of χ-Fe5C2catalyst and the crucial effects of promoters on the FTO performance from theoretical and experimental viewpoints, aiming to provide new insights into the rational design of iron-based FTO catalysts. ? 2016 Science Press

关键词： Carbides Catalyst deactivation Catalysts Iron olefins Phase composition

Preparation of selenofunctionalized heterocycles via iodosobenzene-mediated intramolecular selenocyclizations of olefins with diselenides

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Chinese Chemical Letters 2021年第8期32卷 2587-2591页

作者： Peng-Fei Wang Wei Yi Yong Ling Liang Ming Gong-Qing Liu Yu Zhao School of Pharmacy Nantong UniversityNantong 226001China

An intramolecular selenocyclizations of olefins mediated by a commercially available hypervalent iodine(Ⅲ) reagent,PhIO,was developed.This method provided access to a wide range of selenenylated heterocycles under ambient conditions.The striking advantages of this protocol over all previous methods include mild reaction conditions,easy operation,good yields,high levels of functional group compatibility,large-scale application and suitability for the late-stage functionalization of complex molecules of biological importance.

关键词： Selenocyclizations olefins Heterocycle Iodosobenzene Diselenides

Electrochemical synthesis of β-hydroxy-, β-alkoxy-, and β-carbonyloxy sulfones by vicinal difunctionalization of olefins

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Chinese Chemical Letters 2019年第8期30卷 1509-1511页

作者： Zhefan Zhang Jiyao Yan Dengke Ma Jianwei Sun Shenzhen Research Institute The Hong Kong University of Science and Technology(HKUST)Shenzhen 518057China Department of Chemistry The Hong Kong University of Science and Technology(HKUST)Hong KongChina

An electrochemical vicinal heterodifunctionalization of olefins for the synthesis ofβ-oxysulfones is described.With suitable choice of the conditions,including current,electrodes,and electrolyte,this oxidation reaction proceeded efficiently in an undivided cell without the use of a stoichiometric chemical oxidant.In addition to the previously established synthesis ofβ-hydroxysulfones in the presence of water,minor modification of this protocol by using either external alcohol nucleophiles or internal carboxylic acid nucleophile also led to the synthesis ofβ-alkoxysulfones,andβ-sulfonyl lactones.

关键词： olefins Difunctionalization Electrochemical synthesis Sulfones